1 survey system design_and_engg

04/15/23 Debasis Ghosh 1

SURVEY, SYSTEM DESIGN, ENGINEERING AND BID SUBMISSION FOR LOS AND OFC LINKS

CONTENTS1. Parameters for path loss calculations2. Survey of LOS links:• Preliminary survey• Map studies• Detailed survey3. Feasibility study and report generation4. Link budget calculations for OFC links5. Preparation of bids:• Survey specific to the country• Survey for line of sight links• Survey for OFC links.• Project estimate and finalization of bids6. Post-bid survey & finalization of B.O.Q.


LINE OF SIGHT LINKS (LOS)(PURPOSE AND REQUIREMENT)

1. Purpose• For the establishment of short / long haul LOS links• Feasibility studies• Submission of tenders• Up gradation of existing links2. Requirements of LOS links• Signals follow straight lines• Signals are affected by free space attenuation and

precipitation• Use of frequencies greater than 150 MHz• Use of spread spectrum and time sharing techniques


TRANSMISSION CONCEPTS

A simplified transmission system:

TransmitterReceiver

Transmission Media



Types of Media:

1. Open wire copper cable system

2. Coaxial cable systems

3. High frequency radio communication systems

4. Line of sight communication systems

5. Troposphere scatter systems

6. Satellite communication systems

7. Optical fiber cable systems


TRANSMISSION CONCEPTSTransmission Concepts:1. Decibel (dB):- The decibel is a unit that describes a ratio.

Number of decibels (dB)=10 log10 P2/P1, P1 is lower and P2 is higher power.

2. dBm:- Is a power level related to 1 m W power (0 dBm=1 mW)Power (dBm) = 10 log power (mW)/1 mWIf power of an amplifier is 20 W, What’s it output in dBm?Power dBm = 10 log 20x103 mW/1 mW = + 43 dBm(Plus sign indicates that the quantity is above reference of 0 dBm)If input to a network is 0.0004 W, What’s the input in dBm?Power dBm = 10 log 4 x 10-1 mW/1 mW = - 4 dBm(minus sign indicates that the quantity is below reference of 0 dBm)

NetworkP1 P2

If P1=1W P2=2WGain dB=10 log 2/1 =3 dB

P1=1000WP2=1WLoss dB=10 log 1000/1 =30 dB


TRANSMISSION CONCEPTS3. dBW:- is extensively used in

microwave applications. It is an absolute decibel unit referred to 1W.

Power level (dBW) = 10 log power (W) /1 W (+30 dBm=0 dBW)

4. dBmV:- is extensively used in video transmission. It is voltage level in decibels above and below 1 mV across 75 Ω.

Voltage level dBmV

=20 log mV/1 mV

10 V = + 80 dBmV

1V = + 60 dBmV

1mV = 0

1µV = -60 dBmV

dBm dBW Watts

+66 +36 4000

+60 +30 1000

+33 +13 20

+33 +3 2

+30 0 1

mill watts

+30 0 1000

+27 -3 500

+20 -10 100

+10 -20 10

+7 -23 5

0 -30 1

-10 -40 0.1



Signal-to-Noise Ratio: The signal-to-noise ratio expressed in decibels (dB) is the amount by which a signal level exceeds its corresponding noise.

S/N dB = Signal Level dBm – Noise Level dBm

Noise Figure: All networks active or passive contribute noise to a transmission system. The noise figure is a measure produced by a practical network compared to an ideal network i.e. one that is noise less. For a linear system noise figure is expressed by:-

NF (dB) = 10 log 10 Signal-to-Noise in / Signal-to Noise out

0

20

30

60

Noise

Signal

Frequency



Effective Isotropic ally Radiated Power (EIRP): This is an antenna performance expressed in dBm or dBW over an isotropic antenna, which radiates energy uniformly in all directions and has a gain of 1 or 0 dB and is an imaginary antenna used as a reference.

High Frequency Radio (HF): Radio frequency transmission between 3 and 30 MHz is called HF. HF propagation is characterized by ground waves and sky wave component.

• Ground waves follow surface of the earth and can provide useful communication up to about 650 Km.

• Sky waves permits reliable communication (up to 90 % path reliability) for distances of 6500 Km and even more. The ionosphere is the key to HF sky wave communication*.



Terminal, Repeater (R/R), Drop Insert, Hop and Link concept for LOS links:

Terminal-A

Terminal-B

Drop Insert-4 Drop Insert-8

R/R-1 R/R-2

R/R-3

R/R-5

R/R-6

R/R-7

R/R-9

Hop-7

Hop-1 Hop-2

Hop-3

Hop-4 Hop-5

Hop-6

Hop-8

Hop-9

Hop-10

Microwave Vs OFC Route

130 Km

139 Km

65 Km


LINE OF SIGHT LINKS (LOS)(LINK ENGINEERING)

1. Selection of sites which are in line-of-sight of each other2. Selection of an operational frequency3. Development of path profiles to determine economic tower

heights4. Path calculations so as to achieve• Desired reliability for given fade margin and threshold level5. Making path survey to ensure correctness of steps 1-46. Equipment configuration to achieve fade margins7. Establishment of frequency plan8. Finalization of bill of quantities9. Placement of orders for equipments & towers10. Installation testing and commissioning of links


LINE OF SIGHT LINKS (LOS)(LINK ENGINEERING)

GENERAL FREQUENCY ASSIGNMENTSFREQUENCY (GHz) WAVE LENGTH (CM)

1. P BAND 0.225-0.390 133.3-76.92. L BAND 0.390-1.550 76.9-19.33. S BAND 1.55-5.20 19.3-5.774. X BAND 5.20-10.90 5.77-2.755. K BAND 10.90-36.00 2.75-0.8346. Q BAND 36.00-46.00 0.834-0.6527. V BAND 46.00-56.00 0.652-0.5368. W BAND 56.00-100.00 0.536-0.300EACH BAND IS FURTHER DIVIDED INTO SUB-BANDS


PARAMETERS FOR PATH LOSS CALCULATIONS(Limitations of Line of Sight Systems)

How far we can go: The range of LOS microwave systems is limited by:-• Curvature of earth• Technical radio characteristics (K-factor)• RF effect of fresnel zone• Transmitter power• Antenna gains• Path loss• Transmission line losses• Frequency of operation• Received power• Receiver threshold• Signal to noise ratio• Fade margin required• Desired reliability of link


PARAMETERS FOR PATH LOSS CALCULATIONS(Design of Line of Sight Microwave Links)

Link Design: The design of microwave links, involves three sets of calculations.

1. Working out antenna heights for the link.• K-factor is major dominant variable.• Earth bulge.• Fresnel zone radius.• Operating frequency.• Path profile: it indicates the distance from one of the transmitter

site where obstructions to the line of sight radio link may occur.The object of this calculation is to arrange tower heights along the

entire route of the link, so that an obstruction in the path does not enter into the fresnel zone by a specified amount for a specified K-factor used.


PARAMETERS FOR PATH LOSS CALCULATIONS(Design of Line of Sight Microwave Links)

2. To determine equipment and other parameters for each hop.• Transmit power.• Antenna type and gain.• Transmission type.• Other losses. (Absorption, Diffraction, Reflection or Scattering etc.)• Maximum received power.• Receiver threshold.This will decide the thermal fade margin, which we will be able to get for each

hop.3. To determine the reliability of each hop and overall reliability of the

link.• Climatic factor.• Terrain roughness.• Average annual temperature.This will decide, what is total expected outage time per annum for each hop as

well as for the entire link.


PARAMETERS FOR PATH LOSS CALCULATIONS(Free Space Loss)

PROPAGATION:1. Free space loss: consider a signal is traveling between transmitter at

“A” to a receiver at “B”. There is for a given frequency and distance, a characteristic loss. This loss increases with both distance and frequency. It is known as free space loss.Free space loss LdB=92.44+20 log10 F+20 log10 DWhere F is in GHz and D is in km's.If D is 40 Km and F is 6 GHz, then free space in dB

LdB=92.44+20 log 40+20 log 6

=92.44+20*1.6021+20*0.7782

=92.44+32.042+15.564=140.046 dB

(


PARAMETERS FOR PATH LOSS CALCULATIONS(Free Space Loss)

Free space loss:• Example:- Free space loss if F=2.5 GHz and D=30 Km

FSL (dB) = 92.44 + 20 log 2.5 + 20 log 30=92.44 + 20*0.398 + 20*1.478 =92.44 + 7.96 + 29.56 = 129.96 dB

Now, if F=7.5 GHz (changed) and D=30 Km (unchanged)FSL (dB) = 92.44 + 20 log 7.5 + 20 log 30

=92.44 + 20*0.875 + 20*1.478 =92.44 + 17.5 + 29.56 = 139.5 dB

Now, if F=2.5 GHz (unchanged) and D=40 Km (changed)FSL (dB) = 92.44 + 20 log 2.5 + 20 log 40

=92.44 + 20*0.398 + 20*1.602=92.44 + 7.96 + 32.04 = 132.44 dB

It can be seen, that, free space loss increases both with distance and frequency


PARAMETERS FOR PATH LOSS CALCULATIONS (Fictitious Earth Curvature)

2. Earth bulge and K-factor:• The propagation of radio beam is affected by atmospheric conditions and the

obstructions on the way. It can be subjected to:DiffractionReflectionRefraction

Most important is refraction, which is caused by changes in the density of atmospheric layers confronted by the radio beam front.

• The curvature of earth and slight bending of waves as it is refracted downwards by the earth’s atmosphere are two factors, that, must be considered while making path profiles.

• The earth’s curvature and microwave beam refraction are combined to form fictitious earth curvature or earth bulge.

• EARTH CURVATURE (M) = 0.078 x d1 x d2 / K• WHERE K = EFFECTIVE EARTH RADIUS/TRUE EARTH RADIUS

EARTH BULGE = d1 x d2 / 12.75 x KEARTH BULGE FOR K=4/3 = d1 x d2 / 17EARTH BULGE FOR K=2/3 = d1 x d2 / 8.5


PARAMETERS FOR PATH LOSS CALCULATIONS ( TOWER HEIGHT FOR DIFFERENT VALUES OF K)

ACTIVITY UNIT F=6.5 GHz

F=6.5 GHz

F=2.4 GHz

F=2.4 GHz

d1 distance from higher station Km 15 16 21 22.5

d2 distance from lower station Km 15 16 21 22.5

D hop distance Km 30 32 42 45.0

Ea higher HASL M 400 400 400 400

Eb lower HASL M 300 300 300 300

Ep height of obstruction M 330 330 330 330

Earth bulge for K=4/3 (d1 x d2 /17) M 13.23 15.06 25.94 29.78

Earth bulge for K=2\3 (d1 x d2/8.5) M 26.46 30.12 51.88 59.56

F first fresnel zone radius M 19.76 20.44 40.60 42.18

0.3 F M 5.93 6.13 12.18 12.66

Clearance CL-1=K 4/3 + F M 32.99 35.50. 66.54 71.96

Clearance CL-2=K2/3 + 0.3 F M 32.39 36.25 64.06 72.22


PARAMETERS FOR PATH LOSS CALCULATIONS (EARTH BULGE FOR VARIOUS K- FACTORS)

h

d

DEPARTURE FROM A LEVEL TANGENT, h

DIS

TA

NC

E F

RO

M C

EN

TE

R O

F P

AT

H d h=2d2/3K

K=4/3

K=1

K=2/3

K=5/12

K=1/2

K=7/6

15

10.58

112 225

h is in feet and d is in miles


PARAMETERS FOR PATH LOSS CALCULATIONS(Fresnel Zone)

3.3. Fresnel zone:Fresnel zone:• The radio beam energy travels in an ellipsoidal wave front, the

different components of which maintains different path lengths.• The distance from microwave beam’s center is commonly

measured in fresnel zones to take into account both frequency and distance.

• The first fresnel zone (FFZ) is the surface of the point along which the distance to the ends of the path is exactly ½ wave length larger than the direct end to end path.

• FFZ radius in meters=17.32√d1*d2/fDWhere d1 & d2 are in km’s, f is the frequency in GHz and D is the hop distance in Km’s.

• In order to achieve a free space propagation condition for a radio beam at least 60 % of FFZ should be cleared under the standard atmospheric condition of K=4/3.


PARAMETERS FOR PATH LOSS CALCULATIONS(Fresnel Zone)

FFZ radius in meters=17.32√d1*d2/fD, 1. If f=2.5 GHz and D=30 Km, then FFZ=32.99 M2. If f=4.5 GHz and D=30 Km, then FFZ=24.03 M3. If f=6.5 GHz and D=30 Km, then FFZ=19.75 M4. If f=7.5 GHz and D=30 Km, then FFZ=17.32 M5. If f=18.5 GHz and D=30 Km, then FFZ=11.43 MFFZ radius decreases with increase in frequency.1. If f=2.5 GHz and D=30 Km, then FFZ=32.99 M2. If f=2.5 GHz and D=34 Km, then FFZ=35.33 M3. If f=2.5 GHz and D=36 Km, then FFZ=36.46 M4. If f=2.5 GHz and D=40 Km, then FFZ=38.64 M5. If f=2.5 GHz and D=50 Km, then FFZ=43.73 MFFZ radius increases with increase in distance.


PARAMETERS FOR PATH LOSS CALCULATIONS(KNIFE-EDGE LOSS CALCULATIONS)

-1 -0.5 0 0.5 1.0 1.5 2.0 2.5-40

-30

-20

-10

0

+10

FRESNEL ZONE NUMBERS 1 2 3 4 5 6

R=1.0

R=0.3

R=0

dB

OBSTRUCTION ZONE INTERFERENCE ZONE

R= REFLECTION COEFFICIENT

CLEARANCE / FIRST FRESNEL ZONE

R=1.0

R=0


PARAMETERS FOR PATH LOSS CALCULATIONS(FIRST FRESNEL ZONE AND EARTH BULGE)

NATURAL EARTH FEATURES

EARTH BULGE

FIRST FRESNEL ZONE RADIUS

“A” “B”

T

BUILDING

d1 d2

D

f


PARAMETERS FOR PATH LOSS CALCULATIONS(PROPAGATION CONDITIONS)

PERFECT IDEAL AVERAGE DIFFICULT BAD

STANDARD ATMOSPHERE

NO SURFACE LAYER OR FOG

SUB-STANDARD, LIGHT FOG

SURFACE LAYERS, GROUND FOG

FOG, MOISTURE OVER WATER

TEMPERATE ZONE, NO FOG, NO DUCTING, GOOD ATMOSPHERE, MIX DAY & NIGHT

DRY, MOUNTAINOUS, NO FOG.

FLAT, TEMPERATE, SOME FOG

COASTAL COASTAL, WATER, TROPICAL

K=1.33 K=1.00-1.33 K=0.66-1.00 K=0.66-0.50 K=0.50-0.40


PARAMETERS FOR PATH LOSS CALCULATIONS

(REFLECTION POINT) • The reflection point area lies between a k-factor of grazing (k=1)

and a k-factor of infinity.• From the profiles, possible reflection points can be obtained.• The object is to adjust tower heights, such that, the reflection point

is adjusted to fall on land area, where the reflected energy is broken up and scattered (forest/wooded area).

• Water bodies and other smooth surfaces cause reflection, which is undesirable.

• Figure will assist in adjusting the reflection point.• It uses a ratio of tower heights h1/h2, where shorter tower is always

h1 and distance expressed is always from h1.• By adjusting the ratio h1/h2 the reflection point can be moved.• For a highly reflective path, we may go in for space diversity.


PARAMETERS FOR PATH LOSS CALCULATIONS

(REFLECTION POINT)

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0

1.0

0.1

0.2

0.3

0.4

0.5

Ratio of Tower Heights h1 / h2

d1 /

DD

ista

nce

to

Ref

lec

tio

n P

oin

t/T

ota

l D

ista

nce

K of Grazing

K of Infinity


PARAMETERS FOR PATH LOSS CALCULATIONS(DIVERSITY OPERATION)

Diversity Operations is based on the fact, that, radio signals received over different paths will have different levels i.e. if one is faded, other may not. The separation may be in:

• Frequency• Space (Including angle of arrival and polarization)• Time (a time delay of two signals on parallel paths)• Path (signals arrive on separate paths)

Most common are Frequency (separated by 2-3 %) and Space (separated by 100-200 λ, so that the reflected wave travels ½ wave length further than the normal path). The space diversity improvement can be calculated by Vagrant's formula applied to fading margins. The improvement factor on fading margin is:Le=10 log (1.2 x10-3 x S2 x V2 x fm/d), where:S= Separation between the antenna’sV= Power ratio between the two receiversf = Frequency in GHzm= Selective margin (Number)d= Hop distance in Km’s

Improvement is limited to 200.


PARAMETERS FOR PATH LOSS CALCULATIONS(RECEIVER SENSITIVITY, FADE MARGIN AND SIGNAL TO NOISE RATIO)

Receiver Sensitivity: Sensitivity or Threshold Power of receiver is the level of signal which would produce a 30 dB signal to noise ratio out of the base band of an analogue receiver, or a bit error ratio (BER)=10-4 out of the base band of a digital receiver. Typically it is -80 to -90 dB.

Fade Margin: The fade margin is the power level, that, the unfaded received signal can fall to until it reaches the receiver threshold. This margin will vary depending on geographic and climatic conditions of different geographic areas and desired reliability of the system. Typically it is 20-40 dB.Fade Margin dB=Prx-Pthresh

Signal to Noise Ratio: It’s the minimum power difference between the wanted received signal and received noise.Signal/Noise Ratio (dB)=10 log10 (Signal Power/Noise Power)Typically it is > 50 dB, logically it should be more than the Fade Margin, so that it is always below the threshold level.


PARAMETERS FOR PATH LOSS CALCULATIONS(System and Link Reliability)

Reliability of the link: Outage time for each hop and for the complete link is to be worked out, which in turn will give the over all reliability of the link in terms of percentage. Rayleigh fading chart is given below.Single hop reliability (%) Fade Margin

99.9 28 dB99.99 38 dB99.999 48 dB

CCIR defines its availability objective for radio relay systems over a hypothetical reference circuit as 99.7 %. Resulting unavailability 0.3 % is of three components.Outage due to power failureOutage due to equipment failureOutage due to propagationIt is reasonable to allot 50 % of the outage time to power and equipment failures and 50 % for propagation. Considering propagation alone, system should have an availability (reliability) of 99.85 % apportioned across the 2500 Km route. This provide guide to establish a per hop propagation reliability for a particular system.Planner rather first set the limit for the reliability and for wide band links it is better than 99.99 %.


PARAMETERS FOR PATH LOSS CALCULATIONS(LOS LINK – GAINS AND LOSSES SIMPLIFIED)

ANTENNA GAIN

LINE LOSSES

FREE SPACE LOSS=140 dB

ANTENNA GAIN

LINE LOSSES

7 GHz

EIRP= + 27.5 dBW

0 dBWLINE LOSS EACH=2.5 dB

ANTENNA GAIN EACH END=30 dB

32.2 Km

-100 dBW

-85 dBW

RECEIVER

INPUT

TRANS POWER=+30 dbm

ANTENNA GAINS=+60 dB

TOTAL GAIN= 90 dB

FREE SPACE LOSS=140 dB

LINE LOSSES=5 dB

TOTAL LOSSES=145 dB

RECEIVED LEVEL= 90 – 145 = - 55 dbm

dB


PARAMETERS FOR PATH LOSS CALCULATIONS(DETAILED PATH LOSS CALCULATION SHEET)

Site from: to:Link name:Equipment type:Frequency:Transmit power:Nominal received power:Receiver threshold:Desired fade margin:Desired reliability:Hot standby / frequency diversity and / or space diversity:Azimuth A – B:Azimuth B – A:Path length:Path length:



SL.

NO.

DESCRIPTION ADD OR

SUBTRACT

UNIT COMMENTS

1 FREE SPACE LOSS MINUS dB

2 CONNECTOR LOSSES (SUM) MINUS dB SUM OF TRANS. AND

RECEIVE

3 CIRCULATOR LOSSES (SUM) MINUS dB SUM OF TRANS. AND

RECEIVE

4 POWER SPLIT LOSSES (IF ANY) MINUS dB

5 DIRECTIONAL COUPLER LOSSES (SUM) MINUS dB SUM OF TRANS. AND

RECEIVE

6 TRANSMISSION LINE LOSSES (SUM) MINUS dB SUM OF TRANS. AND

RECEIVE

7 OTHER LOSSES (SUM) MINUS dB RECT. TO CIRCULAR

WAVE GUIDE

8 ANY OTHER LOSSES (RADOM) MINUS dB

9 SUM OF LOSSES dB



SL.

NO.

DESCRIPTION ADD OR

SUBTRACT

UNIT COMMENTS

10 TRANSMIT POWER PLUS dbm

11 TRANS ANTENNA GAIN PLUS dB

12 TRANSMIT REFLECTOR GAIN OR LOSS PLUS OR MINUS dB

13 RECEIVE ANTENNA GAIN PLUS dB

14 RECEIVE REFLECTOR GAIN OR LOSS PLUS OR MINUS dB

15 SUM OF GAINS dB

16 INPUT LEVEL TO RECEIVER (9-15) dbm

17 RECEIVER THRESHOLD dbm

18 FADE MARGIN dB

19 DIVERSITY IMPROVEMENT NO

20 RELIABILITY OF THE HOP %

21 OUTAGE BOTH WAYS - SECONDS SECONDS


SURVEY OF LOS LINKS(PRELIMINARY SURVEY)

Topography of an area is to be extensively studied with the help of detailed survey maps.

• Initial study of the given link• Aerial/quick survey of terrain/map study• Selection of media of communication

LOS/OFC/Satellite etc• Formulation of best route & an alternate route• Selection of tentative sites & repeaters• Most techno economical media and route to be

finalized


SURVEY OF LOS LINKS(PRELIMINARY SURVEY)

1. Points to ponder for site selection• Near approach roads for accessibility• Near power supply lines to avoid solar power• Small hillocks gives height advantage &

reduced tower heights• Avoid lakes big water reservoirs• Dense forests fine• Study of other routes around the area


SURVEY OF LOS LINKS (MAP STUDIES)

It will be found, that, a through map study will narrow down the problem considerably particularly in case of multi-repeater systems with a wide range of choices. By checking a number of possible routes from map data alone, it will be usually possible to reduce the choice down to a few alternatives

1. Survey maps are available for every country & now digitized in most of the countries

2. Survey of India Topographical maps in different scales of (1:250,000, 1:50,000 and 1:25,000) provides most excusive information

3. India’s co-ordinates are• Longitude 68 to 96 degrees E• Latitude 8 to 36 degrees N4. For preliminary survey i:2,50,000 scale or larger scales to be studied

where as for detailed survey 1:50,000 or 1:25,000 scales are required5. Tentative sites to be marked on the maps6. Each hop needs detailed study for working out exact tower heights


SURVEY OF LOS LINKS (MAP STUDIES-INDEX OF MAPS)

43 52 61

39 44 53 62 71 77 82

40 45 54 63 72 78 83

41 46 55 64 73 79 84

47 56 65 74 85

48 57 66 86

49 58 878º

12º

16º

20º

24º

28º

32º

36º

68º 72º 76º 80º 84º 88º 92º 96ºLongitude E of Greenwich

La

titu

de

N



Survey of India have divided India in to blocks and maps numbered. Each 1:250,000 sheet contains sixteen 1:50,000 sheets, which are numbered from 1-16 i.e. say number 84 is divided into 16 segments 84 A to 84 P as

shown opposite. Each such map is in the scale of 1: 250,000.

A1:2,50,000

Scale

E I M

B F J N

C G K O

D H L P



Each segment is further divided in to 16 sections say 84 A/1 to 84 A/16, which are 1:50,000 scale. For 1:25,000 scale maps, each map is further divided into 4 viz 84 A/2 will have 84A/2/NW, 84A/2/NE,84A/2/SW and 84A/2/SE.

Most likely sites will be located on different maps, which may have to be joined to study individual hops

11:50,000

Scale

5 9 13

1:25,000

NW NE

SE

SW

6 10 14

3 7 11 15

4 8 12 16



PATH PROFILING1. After tentative terminals or repeater sites are selected, draw a straight

line on maps connecting two adjacent sites2. Carefully trace from one site to another, marking all obstacles or

obstructions and possible points of reflection3. Mark the mid point, which is point of maximum earth bulge and to be

marked as obstacle4. Path profiles are plotted on rectangular graph paper or recorded for

feeding in to computer5. HASL of all obstacles between two sites marked on the map are to be

taken in to account at 1-2 km interval6. Carefully mark water bodies viz lakes, rivers, ponds etc for evaluation of

reflection points.7. Contour interval is at 5/10/20 M, bench mark heights can be located in

the maps, heights of most of the hill tops is also given.8. Study of maps will give an idea, which of the critical points have to be

visited and how to approach them during actual survey.


SURVEY OF LOS LINKS (MAP STUDIES-RELEVANT POINTS TO BE CHECKED FOR PATH PROFILING )

1. Contour interval: It may be at intervals of 5,10, 20 M or more.

2. Bench Marks and other heights: It is required to ascertain the HASL of site in question.

3. Roads, cart tracks, foot paths: For approach to site and to look around for any obstruction on both sides in a hop.

4. Dams, rivers, lakes and other reflecting bodies: For any reflection points in a hop.

5. Hills, sand dunes, rocky slopes, cliffs: For any critical obstruction points (OB).

6. Town, villages, towers, chimneys: For calculating OB points.

7. Communication Towers, Broadcasting stations, TV stations, Airports: For checking interference from other media.


SURVEY OF LOS LINKS (DETAILED SURVEY - LIST OF INSTRUMENTS)

1. Laptop or pocket computer2. Global positioning system (GPS)3. Digital or analogue THEODOLITE with compass as an

attachment4. Barometric altimeter 0.5 m resolution5. High resolution binoculars6. Camera7. WALKI-talkie 1.2 GHz RANGE8. WALKI-talkie vhf range9. Prismatic compass10. Mirrors (tailor made)


SURVEY OF LOS LINKS (DETAILED SURVEY - LIST OF INSTRUMENTS)

11. Safety belts12. Measuring tape-50 m13. Measuring tape-5 m14. Polarized camera15. ROTRING scale 1:100, 125, 200, 250, 500, 75016. Leveling staff17. Magnifying glass18. Stationary items19. Topographical instruments20. Hammer and pegs


SURVEY OF LOS LINKS (DETAILED SURVEY – GPS APPLICATIONS)

1. Measurements of exact latitude, longitude and altitude of site or for bench marking.

2. Measurements of areas without triangulation.

3. Oceanic and en route navigation.

4. Precise airfield and landing aid locations.

5. Direct routing of aircraft for fuel saving.

6. Monitoring air craft locations in flight.

7. Search and rescue.

8. Tracking and recovering stolen vehicles.

9. Offshore drilling research.

10. Location of containers in marine terminals.

11. Maintaining security of VIPs.

12. Train control and collision avoidance.

13. Hydrographic surveying.

14. Placing and controlling satellites in orbit.


SURVEY OF LOS LINKS (DETAILED SURVEY – SYSTEM DESIGN)

Path design: the basic purpose in engineering a radio relay path in microwave range is to achieve a path which will meet the requirements for long term medium noise and also ensure, that, outages due to fading, below the predetermined value is minimized.

Regardless of system size, for proper system operation, it is essential for each hop to have adequate clearances under all atmospheric conditions.

To determine clearances, the actual topography of the path and also the height location of obstacles along the path, such as multistoried buildings, chimneys, trees, water bodies are taken into account.

In a relatively flat country a practical rule of thumb is, that, repeater spacing are generally limited to 25-40 Km with tower heights up to 100 M. Actually, it depends on the topography of terrain. Can any one imagine, that, LOS communication to two terminals which are at a distance of 28 Km is possible with six hops having 2 active and 3 passive repeaters*.



Determining precise co-ordinates, ground elevation (HASL), pinpointing potential obstacles on the point-to-point microwave path is a critical part of the design process. Path survey consists of five basic steps.

1. Step one-site documentation:• Site location maps to be studied thoroughly to obtain best access

route to the site• On the way to site make note of the distances and time taken

from a well known reference point-mettle road- un-mettle road-cart road-foot path right up to the site. Description of accessibility to site is very important for the visit by future teams.

• Re-location of site if required • If it is existing site detailed information may have to be collected

from the concerned agency viz existing tower, equipment room, power plant lay outs and their details etc

• All collected data to be re-confirmed



2. Step two-site location verification: if site is new it is to verified from maps, THEODOLITE, electronic distance/height meter, known bench mark position. After proper verification of the site following data is to be collected.

• Site co-ordinates: six digit co-ordinates to be marked. Cross checked by GPS, maps.

• HASL: cross checked from near by bench mark, barometric altimeter of 0.5 m resolution, maps and GPS.

• Marking of tower center from minimum three reference points with bearing angle from north and distance- near by hill top, chimneys, buildings, transmission tower or any permanent structure. This is again important for the visit by future teams.

• Marking of preferably true north/otherwise magnetic north*.• Marking of azimuth (Map) of each antenna and checking of near end

obstructions: use THEODOLITE, prismatic compass and distance height meter.

• Tower height, antenna heights and AZIMUTHAL angles.



• Types and sizes of antenna’s.• Type and length of transmission lines.• Transmitter output power.• Receiver input level, receiver threshold level and requirement of

fade margin.• Check on space diversity requirements.• Number of main and stand by transmitters and receivers.• Laptop/small computer can be very handy at site.• Operating frequencies for future equipments.• Take photographs of site, which may be useful for identification in

future.• Take note of the type of soil and soil samples can be taken for

laboratory testing. This will be useful for economical design of the tower.



If site is existing, complete lay-out of site is to be made.• Existing tower: 1. Type and height of towers, guyed, mast. Take photos.2. Type, heights, AZIMUTHAL angles of each antenna and availability of

space for the type and at proposed height for new antenna’s.3. Availability of space for proposed transmission lines on the run way and at

wave guide entry point to equipment room.4. If there is some problem for items at Para 2 & 3, proposal to be submitted

in report.• Existing equipment, power plant rooms:1. Type of existing equipments, their operating frequencies & power etc. Lay

out to be drawn.2. Type of power plant, capacity, existing loads and spare capacity also in

case solar power is used.3. Take photos for various equipments.



3. Step three-identification of critical points along the path.• On the maps two sites are joined by a thin straight line.• Determine the height, width of all obstructions along the path and

HASL at each point for all potential obstructions. Record the man made obstructions, trees, chimneys etc. all above HASL at 1-2 km Intervals, specially record center point obstruction.

• Allow for future growth of trees and other vegetations for minimum 10 years.

• Visit every likely critical point to ascertain its height and check other parameters.

• Determine the width of water bodies, other reflecting points falling along the route.

• Take mirror tests if after calculations, it is found, that, it is feasible*.

• Some clients insist on propagation tests, which is neither a practical nor viable approach*.


SURVEY OF LOS LINKS (DETAILED SURVEY – SYSTEM DESIGN – MIRROR TEST)

Mirrors required for mirror tests: A perfect way of cross checking LOS.

1. Two mirrors are scratched in the shape of a red cross as shown.

2. Scratched portions are joined back to back, faces are out side.

Size of the mirror shouldbe such, that, it can be heldIn the hand. Mirror is held in hand and light of Sun is allowed to fall on the mirror. Sun light will be seen on the Palm and its reflection in the mirror. Now, the mirror is so adjusted, that, it is directed towards the direction of other station whose Azimuth is known and mirror is tilted such, that, parallax is Removed Between rays falling on the palm and its reflection in theMirror. The person at other siteCan see reflected signal, if LOSIs there.

This test is very useful1. For cross checking of LOS.2. Useful in Metros having high

rise buildings and map studyhas no relevance.

3. Between two hill tops, wheredetailed maps are not availableand many critical obstructions are seen.

4. If LOS is there, one can see mirror up to hundreds of Km’s.

Reflection side of Mirror - 1

Reflection side of Mirror - 2

Scratched side of Mirror 1 & 2



4. Step four-path profile: path profiles are drawn based on the detailed survey report. It can be manually or by computerized software. Hop wise data required is given below.

• Site names.• Co-ordinates of each hop. • HASL of each site• Hop distance (If co-ordinates are fed to computer software, you get hop

distance and azimuthal angles)• HASL of each obstruction and its height including near-end obstructions.• Clearance criteria being adopted.

Say Cl=k 4/3 + 100% ffzAND OR Cl=k 2/3 + 30% FFZ

• Frequency band of operation.With the above parameters antenna heights in each direction of operation can

be worked out and hence the tower height at each sight.



5. Step five-detailed survey report: the report apart from antenna and tower heights already worked out will need reliability calculations for each hop and for the complete link. Determine following parameters.

• Transmitter power• Size and gain of antenna’s for main and diversity operations (if

applicable)• Type and transmission line losses for main and diversity operations (if

applicable)• Other losses• Receiver threshold• Received power of receiver• Signal to noise ratio

We get Fade Margin and reliability/availability for each hop.The complete exercise can be worked out manually with the help of a

calculator. But now a days different Software's are available for Path Loss Calculations, which has made the job simple for the Engineers.


FEASIBILITY STUDIES ANDREPORT GENERATION

CASE STUDY: Feasibility study was carried out for one of the clients for a route length of 2294 Km and report submitted in 2 months. The detailed survey was carried out by three teams in a month’s time. Because of the limitations of the client, we had to visit at least two to three times the number of sites for microwave repeaters than we would have visited in normal case*.Client gave repeat order for another 2000 Km after going through this report and analyzing the recommendations.



CONTENTSCHAPTER DESCRIPTION

LINE DIAGRAM

SURVEY AT A GLANCE

1. INTRODUCTION

2. ORGANIZATION OF THE SURVEY

3. METHODOLOGY USED IN SURVEY

4. ENGINEERING AND TECHNICAL CONSIDERATIONS

5. RESULTS AND PRESENTATION

6. RECOMMENDATIONS

7. SITE DETAILS



CONTENTSCHAPTER DESCRIPTION

8. HOP DETAILS8.1 PATH PROFILES8.2 REFLECTION POINT PROFILES8.3 TOWER HEIGHT CALCULATION SHEET8.4 RELIABILITY CALCULATION SHEET

9. LINK DETAILS9.1 GEOGRAPHICAL INFORMATION9.2 TOWERS AND AERIALS9.3 REFLECTION POINTS9.4 INTERFERENCE CALCULATIONS9.5 FREQUENCY PLAN9.6 OUTAGE TABLE9.7 SYNOPTIC OF THE LINK

10. TECHNO ECONOMIC JUSTIFICATION


FEASIBILITY STUDIES (Line Diagram)

LONG= LONG= LONG= LONG=

LAT = LAT = LAT = LAT =

+

+

+

+

73M/6

73M/7 73M/11

73M/14

73M/15

79A/2 79A/6

79A/11 79A/15

AB

C

D

Km KmKm

GIVE BEARING ANGLES A-B & B-AAS PER ACTUAL DATA RESULTS

GIVE HOP DISTANCES AS PER DATA RESULTS

NOT TO SCALE TYPICAL EXAMPLE


FEASIBILITY STUDIES(SURVEY AT A GLANCE)

FOLLOWING INFORMATION CAN BE GIVEN IN A TABULAR FORM:• SL.NO. 1.• STATION NAME BELMURI• OWNER CLIENT NAME• HASL (M) 11• LONGITUDE 88 08 53 E• LATITUDE 22 56 12 N• ANTENNA HEIGHT (M) TOWARDS 80.2 AND 70.2 HOWRAH

83.4 AND 73.4 BURDWAN• AZIMUTH (DEGREES) 159.32 AND 323.24• HOP DISTANCE (Km) 43.75 AND 46.61• TOWER HEIGHT (M) 90• MAP NO’S 79B/1• REMARKS IF ANY, SAY AIR STRIP NEAR

BY



1. Introduction: Brief is given about the clients floating of an enquiry, submission of the bid by the consultant and subsequent letter of award to carry out feasibility study etc.Details of officers involved in technical discussions and feasibility survey works.

• From clients sidea) Corporate Officeb) Regional Officec) Field coordinatorsd) Survey coordinators

• From Consultants sideFeasibility study was carried out for 2294 Km route length in the states of Orissa, West Bengal and Assam.Details of links are given say,A-B=169 KmB-C=176 Km and so on



Clients Requirements: • Technical specifications and B.O.Q given by the client specified, that, wide

band communication systems needs to be established between various control centers/substations of eastern region.

• Media of communication to be through Microwave System, wherever feasible.

• End terminals to be located at the stations given in the BOQ and Repeaters to be located in any of the manned 33/66/132/220 KV sub-stations on the route.

• In case the Microwave either becomes non-feasible or becomes much costlier due to large number of repeaters, fiber optics is to be considered.

• Optical Fiber Cable to run over 400/220 KV transmission lines between end terminals. Repeater if any has to be considered in any of the manned 33/66/132/220 KV sub-stations to the extent possible, failing which repeaters have to be located on the 400/220 KV transmission lines with Solar Power.



Constraints:• Since repeater (R/R) sites became non-negotiable, it became necessary to

carry out the field survey first by making a visit to terminal stations and proposed R/R’s on any 33/66/132/220 KV sub-stations.

• In the process no of R/R sites to be visited became much more (2-3 times), than, if R/R’s could be negotiable.

2. Organization of the Survey: The survey for this feasibility study was carried out for one month by three different teams simultaneously to meet time schedule of the client.

• Each site (terminals and proposed R/R’s) was visited and map study carried out on the Survey of India Maps of scale 1:50,000. Six digit coordinates were marked by Global Positioning System (GPS) and cross checked on maps.

• Survey related data was collected for the sites and capacity of system data collected from representatives of the client.

• After elimination of non-feasible/extra sites, the selected sites were marked on the site plans and brought forward in the feasibility report.



• The survey of sites was carried out bearing in mind, that, existing towers shall be shared wherever available and feasible for the best usage of available national resources. However, if permission to share the tower is not agreed upon, nearest sites may be chosen for the erection of tower as per minimum height given in the report.

• An integrated communication system of 8 Mbps in the frequency band of 2.3 2.5 GHz was considered for Microwave Systems to cater for Voice and Data Communication for the entire network, whereas 34 Mbps OPGW/ADSS cable was considered, where Microwave was either non-feasible or it becomes costly due to more repeaters were coming in the section or tower height was more than 100 M.



3. METHODOLOGY USED IN SURVEY: Each team used following instruments.

• Global Positioning System (GPS)• Theodolite• Prismatic Compass• Altimeters• Binoculars• Camera• Topographical Instruments• Rodometer• Set of maps 1:2,50,000 and 1:50,000 scale• ROTRING scale and necessary stationary itemsApart from client’s representative, It was necessary to take a local

person to act as a guide to show us different sites.



Following information was collected and points kept in mind during survey.Determination of site’s• Six digit coordinates by GPS and cross checking on maps• HASL i.e. Altitude was checked by Altimeter, GPS and cross

checked on maps• Exact location of plot, lay out of the station, orientation and collection of site data• Accessibility to site, by taking references from known points• Location, altitude and height of obstacles in each hop.• Antenna heights and in turn Tower heights. Towers were kept as low as possible but

up to a limit of 100 M.For this clearance criteria given by the client was kept in mind

0.3 FFZ for K=2/31.0 FFZ for K=4/3, whichever was more stringent (Up to 44 Km)

• Space Diversity was proposed on some of the hops either due to reflection point falling on surface of water or length of hop (not meeting desired reliability)

• Space diversity antenna's proposed at a spacing of 150 λ, which comes to 20 M.



4. ENGINEERING AND TECHNICAL CONSIDERATIONS:• Client’s requirement of varied telecommunication facilities amongst various

dedicated service stations located on existing sites operating in 2.3 to 2.5 GHz band.

• The scheme falls under the category of light capacity routes, still its engineering and design demands careful consideration to ensure high quality, stability and reliability of the entire route.

• Objective is to achieve a path, which will meet requirements for long term noise and ensure, that, outage due to fading is below predetermined values.

• Radio Engineer has to work with many different factors, some of which interact with each other, but he has to come up with solutions which are feasible both technically and economically.

• It is essential for each hop to have adequate clearance under all atmospheric conditions. For this, the actual topography of the path and also obstacles along the path such as multistoried buildings, chimneys, trees, water bodies and other tall structures will have to be taken into account. In relatively flat country R/R spacing is 25-30 Km and Tower height up to 100 M, economy plays a major role for this height limitation. (In HBJ gas pipe line project this limit was crossed with the result weight of 100 M tower was around 85 MT, where as that of 127 M tower was around 185 MT, increasing enormously cost of foundation and tower material)



Map engineering and site selection:• Usually topography of an area is extensively studied before going to the

field.• In this case, since R/R sites were non-negotiable, there was no choice but

to visit the sites first and mark them on the maps.• All the sites visited were marked on the maps, traveling along each path,

collecting information about the type, size, location and characteristics of obstacles, such as, buildings, trees, chimneys, water bodies, low lying areas, river beds, lakes, hills and anticipated critical points. Preliminary profiles were made.

• Map engineering was carried out on Survey of India maps 1:50,000 scale with contour intervals at 10-20 M.

• Work out all the alternatives in the night, eliminate non-feasible and extra sites, take decisions before proceeding further.

• Terminals were fixed by the client, repeaters were to be selected from a number sub-station choices.

• Engineer had to exercise a great deal in selection of repeater sites for the proposed study to meet the path design requirements with regard to:



Clearance criteria: Following criteria was adopted for this scheme.• 1.0 F at K=4/3 ( more stringent up to 44 Km)• 0.3 F at K=2/3 (more stringent beyond 44 Km)Free Space Loss=92.44 + 20 log10 F + 20 log10 D

where F is in GHz and D is in Km.Space Diversity: Vertical antenna space diversity was proposed in few

links, wherever it was found necessary for improving the link reliability. Clearance criteria adopted for space diversity antenna was K4/3+0.6F.

Reflection point: Due care was taken to avoid reflection, but in one case link was across a dam, in which case space diversity was proposed. This was the only case where, space diversity was proposed due to reflection and not because hop was long.


PARAMETERS FOR PATH LOSS CALCULATIONS(TOWER HEIGHT CALCULATIONS)

COMPARISON FOR CLEARANCE CRITERIA BETWEEN (K4/3+1.0F) AND (K2/3+0.3F) WHICHEVER IS CRITICAL

ACTIVITY UNIT F=6.5 GHz F=6.5 GHz F=2.4 GHz F=2.4 GHz

d1 distance from higher station Km 15 16 21 22.5

d2 distance from lower station Km 15 16 21 22.5

D hop distance Km 30 32 42 45.0

Ea higher HASL M 400 400 400 400

Eb lower HASL M 300 300 300 300

Ep height of obstruction M 330 330 330 330

Earth bulge for K=4/3 (d1 x d2 /17) M 13.23 15.06 25.94 29.78

Earth bulge for K=2\3 (d1 x d2/8.5) M 26.46 30.12 51.88 59.56

F first fresnel zone radius M 19.76 20.44 40.60 42.18

0.3 F M 5.93 6.13 12.18 12.66

Clearance CL-1=K 4/3 + F M 32.99 35.50. 66.54 71.96

Clearance CL-2=K2/3 + 0.3 F M 32.47 36.25 64.06 72.22

Slope=(Ea-Eb) d1/D M 50.0 50.0 50.0 50.0

OH (over head clearance) M 15 15 15 15

Tc=(Ep-Ea)+ clearance Max

+ Slope + OH M 27.99 31.25 61.54 67.22



5. RESULTS AND PRESENTATION: Results of survey were displayed in three parts.I) Site Details: a) A data sheet giving:-

• Geographic coordinates and altitude• Station to be served• Reference of map on which station is located• Access sketch with reference to surrounding cities and villages• Details if site is existing• Information about energy• Information about vegetation and soil• Information about towers, aerials, azimuth and more precisely type

of tower and its height• Diameter and height of antenna



b) Orient Sheet Giving:-• A part of the map with indication on site location and direction to

last, next and other sites (if any)• Orientation of the site with reference to some permanent marking

i.e. hill tops, buildings, chimneys, transmission lines or any permanent structure, with approximate distances and azimuthal angle from north. Since all the sites were existing, orientation was not given in the report.c) Site lay out:-Site lay-out at different scales, giving by drawing all the information about the site as found from either, site lay out or information collected from client’s representatives. Proposed location of Tower with respect to control Room was given.



II) Hop Details: • Path profiles:- Path profiles have been drawn on flat earth by

computer for clearance criteria already specified. In case of space diversity links lower antenna height is mentioned. Clearance criteria adopted for space diversity antenna was 4/3+0.6 F.

• Reflection point profiles:- Due care was taken to ensure, that, the reflection points do not fall on water surface/reflecting surfaces by adjusting antenna heights by using PATH LOSS software program Version 3.0.

• Tower height calculation sheet:- The desired information already collected from the field during survey was fed to the computer software to arrive at the tower heights for each hop.

• Reliability calculation sheet:- Going through the clients specifications, equipment is selected which are fed to the computer along with antenna gains and transmission line losses figures. Reliability figures were checked and in case, desired results were not achieved, changes were made to meet the targets.



III) Link Details:I) Geographical informationII) Towers and aerialsIII) Reflection pointsIV) Interference calculationsV) Frequency planVI) Outage tableVII) Synoptic of the link• The above information in the tabular forms was given for the

entire route length.• Wherever, microwave links were not feasible, Fiber Optics was

suggested.



6. Recommendations:• Selection Criteria:- Considering the present and future requirements of client for

voice and data, feasibility study was carried out for 8 Mbps Microwave System in 2.3 to 2.5 GHz frequency band on all feasible links.Optical Fiber System was recommended where Microwave was not either feasible or it was becoming more costly due to more repeaters.Considering the overall requirements of the client, as specified in the tender and discussion with their representatives from time to time, following parameters were kept in mind for preparing this report.MICROWAVE:

Overall reliability was kept better than CCIR limits.Network to provide 120 digital channels of 64 Kbps.Fade margin has been kept 30- 40 dB.Reliability has been worked out for 8 Mbps at 2.4 GHz.

OPTICAL FIBER:Optical Fiber repeater spacing was limited to 100 Km.Optical Fiber Repeaters to be located at 33/66/132/220 KV sub-stations

as for as possible, in the absence of which it was to be kept on tower near road crossings with provision of solar power.



MICROWAVE SYSTEMS:Merits:-

• Optimum use of the capacity by the user. 2.3 to 2.5 GHz are low capacity systems.• Project can be completed quickly on available sub-stations. Delay in acquiring land is

avoidable.• Microwave is slightly cheaper as long as repeater spacing is between 25-40 Km.

Demerits:-• Site clearance from SACFA takes time.• WPC is conserving frequencies and sparing minimum slots.• There is tendency of Microwave becoming costlier than Fiber Optics.• In spite of best design of Microwave System, there could be chances of interference

from other users.• Land acquisition, Tower foundation and erection are time consuming and could cause

delay if sub-soil is rocky or have high water table.• In close proximity of EHT lines, tower erection could hazard and need extra care.• Since repeater stations shall be erected in the campus of other agencies, there could

be coordination problems during execution. Operation and maintenance of the system.



OPTICAL FIBER SYSTEM:Merits:-

• Can be installed on existing or future power lines easily.• In case no dropping of channels is required it can be installed end to end

between two terminals.• Optical fiber is safe, since it is over the EHT lines.• Number of repeaters are far and few, lesser the equipment lesser the

maintenance problems.• Optical fiber cable maintenance can be done along with the EHT lines.• The system provides unlimited capacity and is easily expandable. Extra

capacity can be leased out and generate extra revenue.Demerits:-

• Optical fiber repeaters are to be located in any of the sub-stations failing which they were to be located on 220/440 KV transmission lines with solar power, which could be a vulnerable point in remote areas.

• Failure of transmission towers is likely to disrupt the communication for a longer period.



RECOMMENDATIONS:Feasibility study was carried out for 2294 Km route length to see, if Microwave Systems were feasible on these routes. Though microwave links were feasible on 1334 km as indicated in the report. It was recommended, that, optical fiber cable could be the best communication media for the entire region for the following reasons.

• Single media of communication is the best from execution, operating and maintainability point of view. Microwave cannot be single media, since it is non-feasible on many routes.

• Separate clearances for Frequency and SACFA not be taken.• Co-ordination, operational and maintenance problems with other agencies, where

microwave repeaters shall be falling could be avoided.• Interface problems amongst different media can be avoided.• Microwave system will be used only by nodal agency, whereas if optical fiber is used,

spare fiber can be leased out to other agencies, thereby generating extra revenue.• For microwave systems Royalty and License fee to be paid to DOT is a recurring

expenditure.• OFC system has unlimited channel bandwidth. Future expansion is easy and

relatively less expensive, unlike Microwave Systems.


FEASIBILITY STUDIES AND REPORT GENERATION(SITE DETAILS)

(SITE PARTICULARS CALCUTTA)

Site Particulars: The information for each site to be noted in tabular form.1. Site Name: Calcutta2. Link Name: Calcutta-Durgapur3. Longitude: 88 21 03 E4. Latitude: 22 29 49 N5. Altitude: 6 M6. Operating Frequency: 2400 MHz7. Map Number: 79/B-6 Scale: 1:50,0008. Access to sit: Existing otherwise details to be given.9. Room for Equipment: Available in existing building.10. Type of soil: Normal soil with sand at top.11. Vegetation: Grassy12. Energy: AC and -48 V available13. Tower: Type SS Height 100 M (Existing)14. Antenna: Type Diameter Height Azimuth Towards

DAX-6 1.8 M 50 M 325.33 Howrah15. Remarks: Permission for using existing 100 M tower of DOT to be taken by client.



(SITE MAP AND SITE ORIENTATION)

Map No: 79/ BAzimuth Angle Distance

A= 55º 750 M

B= 120º 1.2 Km

C= 300º 7.9 Km• 325.33

• HOWRAH

• 1:50,000 SCALE MAP

• CALCUTTA

Building

• Hill

•

Road crossing

A

B

C

Proposed Tower center

North



(SITE PARTICULARS BELMURI)

Site Particulars: The information for each site to be noted in tabular form.1. Site Name: BELMURI2. Link Name: Calcutta-Durgapur3. Longitude: 88 08 53 E4. Latitude: 22 56 12 N5. Altitude: 11 M6. Operating Frequency: 2400 MHz7. Map Number: 79/B-1 Scale: 1:50,0008. Access to sit: Existing otherwise details to be given.9. Room for Equipment: Available in existing building.10. Type of soil: Normal.11. Vegetation: Grassy12. Energy: AC available, DC not available13. Tower: Type SS Height 90 M14. Antenna: Type Diameter Height Azimuth Towards

DAX-10 3 M 80.2 M 159.32 HOWRAHDAX-10 3 M 70.2 M 159.32 HOWRAHDAX-12 4 M 83.4 M 323.24 BURDWANDAX-8 2.4 M 73.4 M 323.24 BURDWAN



(SITE LAYOUT PLAN BELMURI)

BELMURI SITE: (NOT TO SCALE)

CONTROL ROOM

SHED

RAMP

20 M

20 M

PROPOSED LOCATION FOR 90 M TOWER

SWITCH YARD

RO

AD

RAILWAY TRACK 50 M

N



(SITE PARTICULARS BURDWAN)

Site Particulars: The information for each site to be noted in tabular form.1. Site Name: BURDWAN2. Link Name: Calcutta-Durgapur3. Longitude: 87 52 32 E4. Latitude: 23 16 25 N5. Altitude: 28 M6. Operating Frequency: 2400 MHz7. Map Number: 73/M-15 Scale: 1:50,0008. Access to sit: Existing otherwise details to be given.9. Room for Equipment: New.10. Type of soil: Normal.11. Vegetation: Grassy12. Energy: AC available, DC not available13. Tower: Type SS Height 100 M14. Antenna: Type Diameter Height Azimuth Towards

DAX-12 4 M 96.5 M 143.13 BELMURIDAX-8 2.4 M 86.5 M 143.13 BELMURIDAX-12 4 M 97.0 M 299.00 MANKARDAX-10 3 M 44.2 M 291.41 Galsi (alternative to

MANKAR)15. Remarks: 100 M cable required from new equipment room to control room.



(SITE LAYOUT PLAN BURDWAN)

BURDWAN SITE: (NOT TO SCALE)

ROAD• KATWA BURDWAN

PROPOSED 100 M TOWER(OPTION-I)

PROPOSED100 M TOWER(OPTION-II)

SWITCH YARD

CONTROLROOM(SINGLE STORY)

OH CABLE

70 M

N



(SITE PARTICULARS MANKAR)

Site Particulars: The information for each site to be noted in tabular form.1. Site Name: MANKAR2. Link Name: Calcutta-Durgapur3. Longitude: 87 32 07 E4. Latitude: 23 25 49 N5. Altitude: 60 M6. Operating Frequency: 2400 MHz7. Map Number: 73/M-11 Scale: 1:50,0008. Access to sit: Kacha road (Motor able).9. Room for Equipment: New.10. Type of soil: Normal.11. Vegetation: Grassy12. Energy: Not available13. Tower: Type SS Height 50 M14. Antenna: Type Diameter Height Azimuth Towards

DAX-12 4 M 48 M 116.42 BURDWANDAX-10 3 M 42 M 313.76 PARULIA

15. Remarks: Since this is new site, suitable space be kept for Eqpt. room and Tower.



(SITE LAYOUT PLAN MANKAR)

MANKAR SITE: (NOT TO SCALE)

DVC WATER SUPPLYFOR IRRIGATION MANKAR RURAL HOSPITAL

PROPOSED 50 M TOWER PROPOSED TELECOM BUILDING

PROPOSED LAND FOR 132 KV SUB STATIONN

MOTOR ABLE ROAD


FEASIBILITY STUDIES AND REPORT GENERATION(HOP DETAILS)

(PATH PROFILE BELMURI - BURDWAN)

BELMURILATITUDE 22 56 12 NLONGITUDE 88 08 53 EAZIMUTH 323.24 DEG.ELEVATION 11 M AMSLANTENNA CL 83.4, 73.4 M AGL

BURDWANLATITUDE 23 16 25 NLONGITUDE 87 52 32 EAZIMUTH 143.13 DEG.ELEVATION 28 M AMSLANTENNA CL 96.5, 86.5 M AGL

PATH LENGTH 46.61 KmFREQUENCY=2400 MHzK=0.66, 0.66% F=30.00, 20.00

20

4060

80

100

120

140

160

0

0 5 10 15 20 25 30 35 40 45

96.5

28 M

11 M

83.4



(REFLECTION POINT PROFILE BELMURI - BURDWAN)

BELMURI – BURDWAN HOP:

0 5 10 15 20 25 30 35 40 45

0

20

40

60

80

100

120

140

160

REFLECTION PLANE DEFINED BETWEEN 0.00 AND 46.61 KmREFLECTION POINT LOCATION AT 22.3 Km

FREQUENCY 2400 MHzFRESNEL ZONE 30.0 %F1



(TOWER HEIGHT CALCULATION SHEET BELMURI-BURDWAN)

BELMURI BURDWAN

LATITUDE 22 56 12 N 23 16 25 N

LONGITUDE 88 08 53 E 87 52 32 E

AZIMUTH 323.24 143.13

DISTANCE (Km) 46.61 46.61

DATUM NAD27 – CLARKE 1866 NAD27 – CLARKE 1866

UTM ZONE 45 45

EASTING (Km) 617.716 589.538

NORTHING (Km) 2536.830 2573.936

ELEVATION (M) 11.0 28

MAIN ANTENNA HEIGHT (M) 83.4 96.5

DIVERSITY ANTENNA HEIGHT (M) 73.4 86.5

FREQUENCY (MHz) 2400 2400

POLARIZATION VERTICAL VERTICAL



(TOWER HEIGHT CALCULATION SHEET BELMURI-BURDWAN)

DISTANCE (Km) ELEVATION (M) OBSTRUCTION HEIGHT (M) AG

0.00 11.2

5.00 10.0 15 T

10.00 12.0 15 T

15.00 12.0 15 T

20.00 15.0 15 T

25.00 20.0 15 T

30.00 24.0 15 T

35.00 25.0 15 T

40.00 26.0 15 T

45.00 20.0 15 T

46.61 28.0



(RELIABILITY CALCULATION SHEET BELMURI - BURDWAN)

bel-bur.p13 - 1 BELMURI BURDWAN

ELEVATION (M) 11.00 28.00

LATITUDE 22 56 12 N 23 16 25 N

LONGITUDE 88 08 53 E 87 52 32 E

AZIMUTH 323.24 143.13

ANTENNA TYPE (MAIN) DAX-12 DAX-12

ANTENNA HEIGHT (M) 83.38 96.46

ANTENNA GAIN (dBi) 38 38

RANDOM LOSS (dB) 0.25 0.25

TX LINE TYPE (MAIN) FOAM 1-1/4” FOAM 1-1/4”

TX LINE LENGTH (M) 105 116

TX LINE UNIT LOSS (dB/100 M) 5.2 5.2

TX LINE LOSS (dB) 5.46 6.03

CONNECTOR LOSS (dB) 1.00 1.00





ANTENNA TYPE (DIVERSITY) DAX-8 DAX-8


ANTENNA GAIN (dBi) 33.5 33.5


TX LINE TYPE (DIVERSITY) FOAM 1-1/4” FOAM 1-1/4”

TX LINE LENGTH (M) 94 107




CIRCULATOR BRANCHING LOSS (dB) 0.5 0.5

TX SWITCH LOSS (dB) 1.20 1.20

TX FILTER LOSS (dB) 2.0 2.0

RX HYBRID LOSS (dB) 2.5 2.5

DIV. RX CIRCULATOR LOSS (dB) 2.5 2.5

OTHER RX LOSS (dB) 3.0 3.0






POLARIZATION VERTICAL VERTICAL

PATH LENGTH (Km) 46.61 46.61

FREE SPACE LOSS (Db) 133.44 133.44

ATMOS. ABSORPTION LOSS (dB) 0.29 0.29

MAIN NET PATH LOSS (dB) 83.42 83.42

DIVERSITY NET PATH LOSS (dB) 81.85 81.96

TX FREQUENCY ASSIGNMENT (MHz) 2400 2400

TX POWER (WATTS) 0.89 0.89

TX POWER (dBm) 29.49 29.49

EFFECTIVE RADIATED POWER (dBm) 57.08 56.5

RX THRESHOLD CRITERIA 10-3 10-3

RX THRESHOLD LEVEL (dBm) -91.00 -91.00

MAXIMUM RECEIVED SIGNAL (dBm) -30 -30





MAIN RX SIGNAL (dBm) -53.93 -53.93

DIVERSITY RX SIGNAL (dBm) -52.36 -52.47

THERMAL FADE MARGIN (dB) 38.64 38.53

CLIMATIC FACTOR 0.5 0.5

TERRAIN ROUGHNESS (M) 6.10 6.10

C FACTOR 1.65 1.65

AVERAGE ANNUAL TEMP. (DEG. C) 28 28

DIVERSITY TYPE SPACE DIVERSITY BB SPACE DIVERSITY BB

SD IMPROVEMENT FACTOR 31.79 31.66

WORST MONTH MULTIPATH 1 WAY (SEC) 2.72 2.80

WORST MONTH MULTIPATH 1 WAY (%) 99.999896 99.999894

ANNUAL MULTIPATH 1 WAY (SEC) 12.24 12.59

ANNUAL MULTIPATH 1 WAY (%) 99.999961 99.999960

ANNUAL MULTIPATH 2 WAY (%-SEC) 99.999921-24.83 99.999921-24.83



(PATH PROFILE BURDWAN - MANKAR)

BURDWANLATITUDE 23 16 25 NLONGITUDE 87 52 32 EAZIMUTH 296.56 DEG.ELEVATION 28 M HASLANTENNA CL 93.2 M AGL

MANKARLATITUDE 23 25 49 NLONGITUDE 87 32 07 EAZIMUTH 116.42 DEG.ELEVATION 60 M HASLANTENNA CL 48 M AGL

PATH LENGTH 38.87 KmFREQUENCY 2400 MHzK = 1.33% F = 100.00

0 5 10 15 20 25 30

20

40

60

80

100

120

35

60 ASL

48 AGL

93.2 AGL

28 ASL

M



(REFLECTION POINT PROFILE BURDWAN - MANKAR)

REFLECTION PLANE DEFINED BETWEEN 0.00 AND 38.87 KmREFLECTION POINT LOCATION AT 24.2 Km

FREQUENCY 2400 MHzFRESNEL ZONE 100 %F1

05 10 15 20 25 30 35 38.87

20

40

60

80

100

120



(TOWER HEIGHT CALCULATION SHEET BURDWAN - MANKAR)

BURDWAN MANKAR

LATITUDE 23 16 25 N 23 25 49 N

LONGITUDE 87 52 32 E 87 32 07 E

AZIMUTH 296.56 116.42

DISTANCE (Km) 38.87 38.87

DATUM NAD27 – CLARKE 1866 NAD27 – CLARKE 1866

UTM ZONE 45 45

EASTING (Km) 589.550 554.688

NORTHING (Km) 2573.930 2591.092




POLARIZATION HORIZONTAL HORIZONTAL



(TOWER HEIGHT CALCULATION SHEET BURDWAN - MANKAR)

DISTANCE (Km) ELEVATION (M) OBSTRUCTION HEIGHT (M) AG

0.00 28.0

11.00 35.0 15 T

13.50 37.0 15 T

20.00 40.0 15 T

21.75 42.3 15 T

37.50 60.0 15 T

38.87 60.0



(RELIABILITY CALCULATION SHEET BURDWAN - MANKAR)

bur-man 1 .pl3-page 1 BURDWAN MANKAR


LATITUDE 23 16 25 N 23 25 49 N

LONGITUDE 87 52 32 E 87 32 07 E

AZIMUTH 296.56 116.42

ANTENNA TYPE (MAIN) DAX-12 DAX-12


ANTENNA GAIN (dBi) 38.00 38.00


TX LINE TYPE (MAIN) FOAM 1-1/4” FOAM 1-1/4”

TX LINE LENGTH (M) 116.00 68.00








CIRCULATOR BRANCHING LOSS (dB) 0.50 0.50

TX SWITCH LOSS (dB) 1.20 1.20

TX FILTER LOSS (dB) 2.00 2.00

RX HYBRID LOSS (dB) 2.50 2.50

RX FILTER LOSS (dB) 2.00 2.00

OTHER RX LOSS (dB) 3.00 3.00


POLARIZATION HORIZONTAL HORIZONTAL

PATH LENGTH (Km) 38.87 38.87

FREE SPACE LOSS (Db) 131.86 131.86

ATMOS. ABSORPTION LOSS (dB) 0.24 0.24

NET PATH LOSS (dB) 79.88 79.88

TX FREQUENCY ASSIGNMENT (MHz) 2400 2400

TX POWER (WATTS) 0.89 0.89





TX POWER (dBm) 29.49 29.49

EFFECTIVE RADIATED POWER (dBm) 56.51 59.00

RX THRESHOLD CRITERIA 10 E -3 10 E -3

RX THRESHOLD LEVEL (dBm) -91 -91

MAXIMUM RECEIVED SIGNAL (dBm) -30 -30

RX SIGNAL (dBm) -50.39 -50.39

THERMAL FADE MARGIN (dB) 40.61 40.61

CLIMATIC FACTOR 0.50 0.50

TERRAIN ROUGHNESS (M) 6.10 6.10

C FACTOR 1.65 1.65

AVERAGE ANNUAL TEMP. (DEG. C) 28.00 28.00

DIVERSITY TYPE NON DIVERSITY NON DIVERSITY





WORST MONTH MULTIPATH 1 WAY (SEC) 31.83 31.83

WORST MONTH MULTIPATH 1 WAY (%) 99.998789 99.998789

ANNUAL MULTIPATH 1 WAY (SEC) 143.22 143.22

ANNUAL MULTIPATH 1 WAY (%) 99.999546 99.999546

ANNUAL MULTIPATH 2 WAY (%-SEC) 99.999092 – 286.44 99.999092 – 286.44


FEASIBILITY STUDIES AND REPORT GENERATION(LINK DETAILS)

(GEOGRAPHICAL INFORMATION)

FOLLOWING INFORMATION CAN BE GIVEN IN A TABULAR FORM:

• SL.NO. 1.• STATION NAME BELMURI• OWNER CLIENT NAME• HASL (M) 11• LONGITUDE 88 08 53 E• LATITUDE 22 56 12 N• AZIMUTH (DEGREES) 159.32 TOWARDS HOWRAH

323.24 TOWARDS BURDWAN• TOWER HEIGHT (M) 90• HOP DISTANCE (Km) 43.75 TOWARDS HOWRAH

46.61 TOWARDS BURDWAN• REMARKS IF ANY SAY AIR STRIP NEAR BY



(TOWERS AND AERIALS)

FOLLOWING INFORMATION IS GIVEN IN A TABULAR FORM:

S.N. STATION

FROM

STATION

TO

ANT.

DIA.(M)

ANT.

HT. (M)

AZIMUTH

DEGREE

TX LINE

(M)

1 CALCUTTA HOWRAH 1.8 50 325.33 70

2 HOWRAH CALCUTTA

BELMURI

1.8

3.3

52.6

84.2,74.2

145.31

339.38

73

105, 95

3 BELMURI HOWRAH

BURDWAN

3.3

4.0,2.4

80.2,74.2

83.4,73.4

159.32

323.24

101, 91

104, 94

4 BURDWAN BELMURI

MANKAR

4.0, 2.4

4.0

96.5, 86.5

93.2

143.13

296.56

117, 107

116

5 MANKAR BURDWAN

PARULIA

4.0

3.0

48.0

41.9

116.42

313.76

68

62

6 PARULIA MANKAR 3.0 55.0 133.69 75



(REFLECTION POINTS)

S. NO. HOP FREQUENCY

(MHz)

HOP

DISTANCE

(Km)

REFLECTION POINT LOCATION (Km)

REMARKS

1 CALCUTTA-HOWRAH 2400 9.75 4.6 NO REF.

ANTICIPATED

2 HOWRAH-BELMURI 2400 43.75 22.3 NO REF.

ANTICIPATED

3 BELMURI-BURDWAN 2400 46.61 22.3 NO REF.

ANTICIPATED

4 BURDWAN-MANKAR 2400 35.33 24.2 NO REF.

ANTICIPATED

5 MANKAR-PARULIA 2400 29.96 12.0 NO REF.

ANTICIPATED



(FREQUENCY PLAN)

26.96 Km

35.33 Km

46.61 Km

43.75 Km 9.75 Km

PARULIA MANKUR

BURDWAN

BELMURI

HOWRAH CALCUTTA

f1’

f1

f1 f1’

f1’

f1

f1 f1’f1’ f1

V

H

V

H

V

AB

C

D

E

F

5085

85

100

5055



(INTERFERENCE CALCULATIONS)

REC.

ST.

W.

S.

F.

W.

S.

F.

XPD

FBD

DD AD OL TOTAL

XPD

FBD

DD AD OL TOTAL

XPD

FBD

DD AD OL TOTAL

A B 20 25 20 65

B A C 25 45 70 25 45 70 8.82

40 20 69

C B D 25 45 70 25 45 70 7.45

30 20 57

D C E 25 45 70 6.53

28 20 54 25 45 70

E D F 25 45 70 10.86

20 20 50.86

25 45 70

F E 11.3

20 20 51



(OUTAGE TABLE)

S.NO. HOP ANNUAL-2 WAY (%)

RELIABILITY

OUTAGE-2 WAY (SEC)

REMARKS

1 CALCUTTA-HOWRAH 99.999987 4.20 NON DIVERSITY

2 HOWRAH-BELMURI 99.999878 38.52 DIVERSITY

3 BELMURI-BURDWAN 99.999921 24.83 DIVERSITY

4 BURDWAN-MANKAR 99.999092 286.44 NON DIVERSITY

5 MANKAR-PARULIA 99.999745 80.40 NON DIVERSITY



(SYNOPTIC OF THE LINK)

29.96 Km 35.33 Km 46.61 Km 43.75 Km 9.75 Km

PARULIA MANKAR BURDWAN BELMURI HOWRAH CALCUTTA

55 M 50 M 100 M 85 M 85 M 50 M

55M

41.9M

48M

93.2M

96.5M

86.5M

83.4M

73.4M80.2

80.2M

70.2M

84.2M

74.2M

52.6M 50.0M


FEASIBILITY STUDIES AND REPORT GENERATION(TECHNO - ECONOMIC JUSTIFICATION)(CALCUTTA – PARULIA (DURGAPUR)

FIBER OPTICS MICROWAVE

SL.NO.

DESCRIPTION QTY. UNIT PRICE (US$)

TOTAL (US$)

SL.NO.

DESCRIPTION QTY. UNIT PRICE (US$)

TOTAL (US$)

1 OFC (12 F) 200 2500 500000 1 RADIO EQPT. S/D 4 24539 98156

2 LAYING OF OFC 200 1250 250000 2 RADIO R/R EQPT. 6 49078 294468

3 LINE TML. (FO) EQ. 4 7500 30000 3 MULTIPLEXERS 4 2500 10000

4 FIBER OPTIC R/R 1 15000 15000 4 SERVICE CH. UNIT 10 1035 10350

5 SERVICE CH. UNIT 4 1035 4140 5 ALARM CON. UNIT 10 2528 25280

6 ALARM CON. UNIT 4 2500 10000 6 NMS 1 26500 26500

7 NMS 1 26500 26500 7 ANT.& TX. LINE SYS. 14 6669 93366

8 MULTIPLEXERS 4 2500 10000 8 TOWERS (80m) 3 70000 210000

9 POWER PLANT 4 8750 35000 9 POWER PLANT 10 8000 80000

10 INST. & COMM. LS 176128 176128 10 INST. & COMM. LS 124836 124836

1056768 972956


LINK BUDGET CALCULATIONS FOR OFC (ADVANTAGES OF FIBER COMMUNICATIONS)

1. High band width: Can carry very large information over long distances.2. Immunity to radio frequency interference:3. Immunity to electromagnetic interference:4. No cross-talk:5. Highly secure and can maintain privacy:6. Small size and light weight:7. Low cost: Cost is coming down day by day.8. Plenty of resources are available: Glass fiber (silicon dioxide) or

transparent plastic are readily available materials.9. Low attenuation: Typical OFC attenuate 0.3 dB/Km.10. OFC is safe: Glass or plastics are insulators, no electric current.11. Corrosion by water and chemicals is less severe than copper.12. Can withstand high temperatures: Range from -25 to 65 degree.13. Very flexible: Easy to lay, where there are many curves.


LINK BUDGET CALCULATIONS FOR OFC (APPLICATIONS OF FIBER COMMUNICATIONS)

1. Long Distance Communication: Land line and under water.2. Junction Network: Very useful for Inter-Exchange Junctions.3. Video Transmission: TV broadcast, Cable TV, remote monitoring

and surveillance.4. Large Data Transfers: Over very large distances or LAN.5. Defense Applications: Communication, command & control links

on ships and aircraft, data links for satellite earth stations.6. Non-communication Applications: Fiber sensors are used to

measure temperature, pressure, rotary and linear positions and liquid levels.

7. Fiber in Local Loop: As an alternative to conventional copper cables in subscriber loop.

8. Use on high Electromagnetic Interference areas: Along the railway tracks, high tension transmission lines.


LINK BUDGET CALCULATIONS FOR OFC (SYSTEM DESIGN CONSIDERATIONS)

System Design Engineer’s job is to design most efficient and cost-effective system. Following points may be considered.

• Transmission requirements: Audio, Data, Video, or combination of these signals?

• One way or bidirectional?

• What is distance?

• What is the optical loss budget being considered?

Transmission losses: Optical loss is the sum of the losses of individual component between transmitter and receiver, which are:-

• Fiber loss/Km

• Coupling loss

• Connector loss

• Splice loss

• Patch panel loss


LINK BUDGET CALCULATIONS FOR OFC (SYSTEM DESIGN CONSIDERATIONS)

Power Budget: It is the maximum amount of signal loss a system can tolerate and still function satisfactorily. In Fiber optic system, the combined components losses must be low enough to ensure, that, sufficient power reaches the receiver. In addition to this, some power is kept reserve as margin for future cable maintenance and aging of different components. After calculation of total losses from the transmitted power, the net received power should be above the receiver sensitivity. Typical optical losses are shown:-

ITEM LOSSES

CONNECTOR ST TYPE 1.0 dB

CONNECTOR FC/PC 0.75 dB

FIBER MULTIMODE @ 850 nm 3.5 dB/Km

FIBER MULTIMODE @ 1300 nm 1.5 dB/Km

FIBER SINGLE-MODE @1310 nm 0.6 dB/Km

FIBER SINGLE-MODE @ 1550 nm

0.4 dB/Km

SPLICE BUTT 2.0 dB

SPLICE MECHANICAL 0.5 dB

SPLICE FUSION 0.2 dB

PATCH PANEL 2.0 dB


LINK BUDGET CALCULATIONS FOR OFC (SYSTEM ENGINEERING SPECIFICATIONS)

SL.NO.

PARAMETERS CHARACTERISTICS

1 TYPE OF FIBER MONOMODE

2 WAVE LENGTH 1300 nm

3 ATTENUATION 0.5 dB/Km

4 SPLICING LOSS 0.1 dB/splice

5 CONSTRUCTION METAL FREE JELLY FILLED 12 F OFC

6 SHRINKAGE 1 % of OF CABLE

7 JOINTS 1 JOINT PER 2 Km

8 EXTRA LENGTH FOR JOINTING 10 M PER JOINT

9 EXTRA LENGTH FOR LEADING IN 100+100=200 M OR ACTUAL

10 FIBER LENGTH 102 % of OF CABLE LENGTH

11 OPTICAL TRANS POWER -3.5 dbm

12 RECEIVER THRESHOLD -39.5 dbm

13 CABLE/EQUIPMENT OPERATION MARGIN 3 dB

14 FDF LOSS 2.5 dB

15 NOMINAL RECEIVED LEVEL -17 dbm TO -36.5 dbm


LINK BUDGET CALCULATIONS FOR OFC (FOR PDH 140 MB/S ROUTES)

SL.NO.

PARAMETERS VALUES VALUES VALUES

1 TOTAL FIBER LENGTH 31.361 27.302 37.339

2 TOTAL CABLE LOSS (dB) 15.68 13.651 18.669

3 TOTAL SPLICING LOSS (dB) 1.6 1.4 1.8

4 FDF CONNECTION LOSS (dB) 2.5 2.5 2.5

5 TOTAL LOSSES (dB) 19.780 17.551 22.969

6 TRANS POWER (dbm) -3.5 -3.5 -3.5

7 RECEIVED LEVEL (dbm) -23.280 -21.051 -26.469

8 RECEIVE THRESHOLD (dbm) -39.5 -39.5 -39.5

9 MARGIN (dB) 3 3 3

10 NOMINAL RECEIVE LEVEL (dbm) -17 TO -36.5 -17 TO -36.5 -17 TO -36.5

11 ATTENUATOR REQUIRED NIL NIL NIL


LINK BUDGET CALCULATIONS FOR OFC (SDH SYSTEMS FOR STM-1, 4, AND 16)

AT 1310 AND 1550 nmS.N. PARAMETERS NOTATION L 4.2 L 4.1 L 1.1 L16.2

1 TRANS POWER (WORST) Tw -3 -3 -5 -1

2 TRANS POWER (BEST) Tb 0 0 0 2

3 RECEIVER SENSITIVITY R -36 -32.5 -34 -28

4 TOTAL GAIN (WORST) Tw-R 33 29.5 29 27

5 CONNECTOR LOSS C 2 2 2 2

6 SPLICE LOSS/Km S 0.1 0.1 0.1 0.1

7 FIBER ATTEN./ Km A 0.25 0.4 0.4 0.25

8 SYSTEM MARGIN M 3 3 3 3

9 OPTICAL PATH PENALTY O 1 1 1 1

10 IF COVERED DISTANCE D 80 47 46 63

11 SPLICE JOINT AT Km OF J 3 3 3 3

12 TOTAL LOSSES C+S(1+D/J)+A*D+M+O 28.77 26.47 26.03 23.95

13 FOR MAX. COVERAGE GAIN=LOSSES (4=12)

14 MAX. DISTANCE (WORST) Km 94.94 54.00 52.85 73.76

15 MAX. DISTANCE (BEST) Km 105.53 60.92 64.38 84.35

16 MARGIN LEFT STILL AVAILABLE GAIN-LOSS (4-12) 4.23 3.03 2.97 3.05

L 4.2 IS STM-4 AT 1550 nm L 4.1 IS STM-4 AT 1310 nm

L 16.2 IS STM-16 AT 1550 nm L 1.1 IS STM-1 AT 1310 nm


PREPARATION OF BIDS(Basic Steps)

1. Timely Purchase of Tender: Cash/Embassy/Agent/Any other source.

2. Making no. of copies and distribution to relevant sections.

3. Thorough study of commercial conditions and take necessary action.• Bidder’s qualification criteria• Bid bond• Power of attorney• All other points relevant to this specific tender, since there can be very wide

variation of commercial conditions.

4. Study of technical specifications, preparation and shooting of letters to different suppliers after going through vendor’s list from Data Bank. Copies of relevant Bill of Quantities (BOQ), technical specifications, commercial conditions and compliance statement required to be enclosed. Keep 7-10 day's margin for receiving the quotes.

5. In case there is Pre-bid conference, venders to be requested to send queries if any before schedule time as specified in the tender document.

6. Pre- bid survey is normally carried out jut after the Pre-bid conference.


PREPARATION OF BIDS(GENERAL SURVEY SPECIFIC TO COUNTRY)

1. GENERAL2. CLIENT3. AGENTS4. GENERAL COUNTRY DETAIL5. SITE CONDITIONS6. MATERIALS7. EQUIPMENT AND VEHICLES8. ACCOMMODATION9. OFFICE AND HOUSE HOLD FURNISHING10. PREVALENT SUB-CONTRACT RATES11. MAN POWER12. IMMIGRATION13. COMMERCIAL CONDITIONS14. IMPORTS 15. TAXES AND DUTIES16. OTHER REGULATIONS



General: Date:1. Name of work:2. Country and area of work:3. Bid submission date:4. Survey period5. Survey man powerClient:1. Organization2. Head3. Structure of organization4. Delegated powers5. Supervisory system6. Financial status of client (Balance sheet)7. Clients shares: Their last quote8. Bank references: Liquidity/Solvency/Over dues9. High commission/Embassy’s assessment of the client



Agents:1. Particulars of Agents: Names, addresses, contact no’s, business

in hand.2. Areas of specialization: Telecom, Govt. business, MNC’s etc.3. Bank references: Balance sheet/Audited report4. Indian Embassy’s/High commissions assessment5. Details of Agents performance6. Negotiated scope/Terms of Agent/Draft MOU7. Scope: Marketing, Work permit, Sponsorship in Tender,

Custom/Tax Clearances, LC/BG/OD and or sub-contractor ship8. Fee payable with break-up of components (proportionate to

collection) in local/foreign currencies into designated local/foreign A/c etc.



Country Details:1. Area, Population, Capital, Local Time Summer/Winter etc.2. Climate: Average rainfall, snow, Min-Max. temp., wind speeds, humidity,

dust/sand storm etc.3. Monetary unit: Lending bank rates of banks, L/C and BG commission

rates etc.4. Exchange Rate: Official and Banks. Variation trends US$, convertibility

and repatriation laws.5. Constitution, Government System and Justice/Legal System.6. Religion7. Electric current, Weights and Measures, Holidays/Working Days/Hours8. Main Cities, means of transport, language.9. Telecom Infrastructure: Along the route and in the work area.10. Local Infrastructure: 11. Gross and Per Capita GNP/GDP and growth in last 3 years. Budgetary

surplus/deficit etc.



Site Conditions:

1. Type of Soil: Ordinary, hard, rocky, hard rock etc.

2. Water Table: Salinity/Alkalinity/Chemical Composition/Hard/Soft. Variation of water table season-wise.

3. Existing Services along the route or in the work area: Right of way/Type of Ducts/H.Holes/M.Holes/Exchanges/RSU/Repeater/Cabinets/Towers.

4. New Routes: Distance Volume Obst./Problems

• On Road

• On Foot Path (Paved)

• Unpaved Area

5. Topographical map of site and route: Altitude/Depth

6. Map of Telecom Network

7. Health, Forest, Environmental, and Wildlife Laws/Provisions affecting site work, cost to be incurred etc.



Materials: Enquiry is to be made for the Availability, sources, lead time, rates etc. for the following materials.

1. Cement, Course Aggregate and Sand.2. Reinforcing Steel3. Shuttering material4. PVC Pipes5. Manhole Covers/Frames6. Manhole Hardware's7. Ready Mixed Concrete8. Bitumen, Asphalt Concrete, Sub-Base for Roads9. Other procurement items as per BOQ of tender document.10. Normal Payment Terms with/without LC.11. Availability of Guarantees for Advance/Retention Release/Performance from

Banks etc.12. Acceptable banks for opening of LC’s13. Acceptability/Prequalification of Venders for Clients.



Equipment and Vehicles: Enquiries to be made for the availability, make, hiring charges, Capital cost (CIF) for following items.

1. Excavator2. Rock breaker3. Loader4. Dump trucks5. Crane truck6. Water tanker7. Roller8. Compactor9. Compressor10. Asphalt cutter11. Generator12. Concrete vibrator13. Concrete mixer14. Cable winch15. Cars, Pick ups and 4-wheel drive and other vehicles.



Accommodation:

S.N. Type Rent Lease period Normal Advance Remarks

1. Office

2. 3-Bed room Flat/House

3. 2-Bed room Flat

4. Store

5. Dormitory

6. General particulars

• If rent is inclusive of maintenance

• If accommodation is furnished or unfurnished

• If unfurnished, what is extra cost to furnish

• For how many months advance is to be paid

• Is advance against BG/Cash down payment



Office and house hold furnishings etc.:S.N. Capital cost Hire charges Imported/Locally available1. Office table/chairs (E)2. Office table/chairs (G)3. Air-Conditioners4. Telephone/Telex/Fax5. Sofa set /Dinning table set/Beds6. Refrigerator/ Washing machine/Cooking range7. Personal computer8. Photocopying machine9. UPS/Inverter10. Petrol/Diesel/Water11. Car for office use12. Van for site use13. postage14. D.G. Set



Prevalent Sub-contractor’s Rates: List of prequalified/client approved contractors to be attached with contact numbers.

S.N. Item Rate Contractor Client Year

• Civil

• Tower works

• Telecom Equipment Installation and Commissioning

• OFC Laying

Immigration:

• Work permit for different categories-with permit period

• Expenses

• Residence permit for families-permit period

• Normal period for completing formalities

• Local laws regarding Social Welfare/Security Costs/Benefits



Commercial Conditions:1. Repatriation of money by individuals2. Repatriation of money by Foreign Co.3. Insurance• Vehicles• Project• Workman compensation• Marine / In transit 4. Banking facilities5. Formalities of opening bank A/c by Foreign Co. for:- (Type of Tender)• Execution of Internationally funded projects;• Execution of locally funded schemes;• Execution as consortium partners with local fellow partners;• Execution through local Joint Venture (JV)• Execution through a local agent6. Currency convertibility for purposes of Para 1 & 2.



Imports:1. Main ports2. Clearing agents (Rates from 3-4 reputed agents)3. Clearing period at Ports / Airports4. Transit insurance charges5. Inland transport: Modes and tarrifTaxes and Duties:1. Import Duty:-General, Major items in BOQ.2. Income tax:- Individuals and foreign Companies.3. Other taxes on items in BOQ.4. Sales Tax/Service Tax/Work Tax/Turnover Tax.5. Excise/VAT6. Octroi/Entry Tax within country/local/provincial level.7. Custom duties/Addle. Duties etc.8. Duty/Tax/Waiver-Exemptions under special conditions.9. General Trends in Duties/Taxes.



Business/Telecom/Municipality/Police Regulations:

1. Road specifications

2. Footpath specifications

3. Specific Requirement for Reinstatements

• If reinstatement by Telecom Bodies as per prescribed specifications allowed?

• If reinstatement by Municipal Authorities or their approved contractors mandatory & if so at what rates?

4. Road cutting permissions

5. Barricading along the routes

6. Safety conditions

7. Security conditions

8. Laws for doing business as a Foreign company:- Service with expatriate manpower/Labour Laws/Registration/etc.


PREPARATION OF BIDS(SURVEY FOR LINE OF SIGHT LINKS)

1. Formation of team for survey

2. Collection of: • Relevant survey instruments/tools etc.• Topographical maps 1:25,000/50,000 scale with contour at 10 M.• Site Profiles/Drawings• Data on existing towers and availability of space Antenna’s/Equipment.• Customers specifications and requirements.• Information about location of Radar Sites and Airports.• Information about existing Terrestrial systems in the area.

3. Map Study as per tender requirements for Co-ordinates, altitude, terrain conditions and LOS conditions.

4. Site survey:- Is carried out for each site to determine:• Access road and approach to site• Longitude, latitude, altitude and availability & stability of power supply.• Soil bearing capacity, weather conditions, availability of Infrastructure etc.


PREPARATION OF BIDS(SURVEY FOR LINE OF SIGHT LINKS)

6. Hop Survey: Map study and terrain between two site of each hop is thoroughly trekked to determine:

• Altitude and heights of Near end obstructions, 1-2 Km points along the LOS route for each hop.

• Water logging and other reflecting areas.• Likely interference from nearby Radar and Airport sites.7. Preparation of Drawings:• Site lay out plan• Path profiles: Clearance criteria (as tender document) , heights of critical

points (as per survey) to be taken into account.8. Finalization of:• Tower Heights:- After Hop wise or due to reflection points equalization. • Received level and reliability calculations as specified in the Tender.9. Finalization of System Design: Transmitter Power, location of Terminals,

Repeaters, NMS, Antenna Size/Type/Gain, TX line-Type/Loss.


PREPARATION OF BIDS(SURVEY FOR OFC LINKS)

Items Required for Route Survey of OFC Links:

1. Rodometer

2. Compass

3. Survey /Geographical/Tourist maps

4. Camera

5. Level with staff

6. Digital Multi meter

7. Calculator

8. Measuring Tape 30 M

9. Measuring Tape 3 or 5 M

10. Safety shoes

11. Torch

12. Hat/cap

13. Umbrella/raincoat

14. Floor marking tape/Permanent Marker pen



Route Index Diagram: Route is invariably fixed by the client is part of the tender document. Survey team has to carry out detailed measurements of the cable route and prepare Route Index Diagram (RID). Following points are to be decided/recorded in the RID and also brought out in tabular formatting.

1. Width with Km readings of rail/road crossings (road cutting), bridges, culverts, streams/rivers (dry/flowing), water logging areas etc.

2. Probable location of joint boxes, terminations and repeaters.

3. Bending of roads, location of manholes/hand holes. This is to decide max. lengths of fiber which can be pulled in one stretch. Normally it is 200-250 m and at bends.

4. Width of high way, boundary of road with high way description.

5. Surroundings, land scape, pits, slopes etc.

6. Type of soil to be excavated for trenching.

7. Km marks, important buildings enroute e.g. school, hospitals, petrol pumps, workshops, branching out of roads etc.

8. City area and area jurisdiction of different concerned authorities.

9. In case site is existing, site details and site lay out plan to be prepared.



Site Survey: This is for the existing sites available on the proposed route.1. Precise location of the site with approach road sketch.2. Contact details of the site in charge.3. Existing lay out plan to be obtained (if available).4. Lay out plan of equipment room, power plant rooms and checking the

availability of space for new equipment and power plant.5. Marking of the proposed equipment.6. Study of the existing power plant which is likely to drive the proposed

equipment.7. Earthing arrangement.8. Cable entry and routing within the building. 9. Study of exchange interface.10. Ready For Installations (RFI) action points to be noted for advance action

of the client in case work is awarded to your company and will be useful during post-bid survey.


PREPARATION OF BIDS(PROJECT ESTIMATE AND FINALIZATION OF BIDS)

Preparation of technical offer and finalization of Bill of Quantities (BOQ): There are tenders in which BOQ are fixed, so after survey it is to be ascertained if it tally's. But most of the cases, many items will be vague e.g. System design and engineering is to be given by the bidder. This is where, survey engineer earns his salary. If your design is technically sound and economical, chances of winning the tender are bright.

1. Negotiation with venders for getting the lowest cost on all the items to be supplied under the bid.

2. May be for major items, even go in for exclusive offers, for which signing of MOU and/or consortium partnership may be required.

3. Ensure, that, all the commercial conditions, technical specifications have been met. All the venders have given compliance statements and bid meets all the requirement of the tender document.

4. Bid bond is ready and requisite RBI permission is there.5. Venders are complying to the time schedule for supply of different items.6. Prepare an execution plan and work out number of teams required to

complete the project in time after material is available at ports/airports of clients country.


PREPARATION OF BIDS(PROJECT ESTIMATE AND FINALIZATION OF BIDS)

Preparation of Cost Estimate for the Bid: An example of a very comprehensive tender having WLL, SDH OFC systems and Digital Microwave system with so many other items has been worked out except the actual pricing.

1. Work out actual cost of all the supply materials on CIF basis.

2. Work out actual cost of services for complete execution of the project including warranty maintenance.

3. Make assessment of other expenses which are anticipated, which will be different for supplies and services.

4. Mark up your offer with margin of profit after going through the market survey, your chances of winning the tender etc. This mark up again will be different for supplies and services.

5. Following slides will give an idea how pricing of any tender is done. This is only an example and not a set procedure. The procedure for preparation of tender differ from person to person and company to company but goal is same to be lowest and win the tender.


PREPARATION OF BIDS(PROJECT ESTIMATE – (A) COST OF SUPPLIES)

SL.NO. ITEM UNIT QTY TOTAL PRICE (US$)

1 SDH SYSTEMS OPTICAL STM - 4 SYSTEMS 22

2 WLL SYSTEMS SYSTEMS 89

3 DIGITAL MICROWAVE SYSTEMS SYSTEMS 20

4 MAIN POWER SUPPLY NO’S 30

5 SOLAR POWER SUPPLY NO’S 53

6 TOWER SUPPLY NO’S 89

7 ANTENNA/ WAVE GUIDE SYSTEMS SETS 89

8 SHELTERS NO’S 89

9 FENCING OF SITES NO’S 54

10 POTS NO’S 4313

11 PAY PHONE NO’S 534

12 DATA NO’S 467


PREPARATION OF BIDS(PROJECT ESTIMATE – (A) COST OF SUPPLIES)

SL.NO. ITEM UNIT QTY TOTAL PRICE (US$)

13 POLES 8/9 M NO’S 4983

14 DUCT NO - 54 M 78140

15 TRIPLE DUCT M 49050

16 SUB DUCT M 79084

17 STEEL DUCT M 494

18 CONCRETE MARKER POSTS NO’S 838

19 STAYS FOR POLES NO’S 1224

20 FIBER OPTIC CABLE 48 F M 51531



23 FIBER OPTIC INTERNAL CABLE M 965

24 AERIAL CABLE M 319143


PREPARATION OF BIDS(PROJECT ESTIMATE – (B) COST OF SERVICES)

SL.NO. ITEM UNIT QTY EXECUTION PLAN

1 SDH SYSTEMS OPTICAL STM - 4 SYSTEMS 22 DEPARTMENTALLY

2 WLL SYSTEMS SYSTEMS 89 DEPARTMENTALLY

3 DIGITAL MICROWAVE SYSTEMS SYSTEMS 20 DEPARTMENTALLY

4 MAIN POWER SUPPLY NO’S 30 DEPARTMENTALLY

5 SOLAR POWER SUPPLY NO’S 53 DEPARTMENTALLY

6 TOWER FOUNDATION AND ERECTION WORKS NO’S 89 SUB-CONTRACTOR

7 ANTENNA/ WAVE GUIDE HOISTING SETS 89 SUB-CONTRACTOR

8 SHELTERS ERECTION NO’S 89 SUB-CONTRACTOR

9 FENCING OF SITES WORKS NO’S 54 SUB-CONTRACTOR

10 POTS INSTALLATION NO’S 4313 SUB-CONTRACTOR

11 PAY PHONE BOOTHS INSTALLATION NO’S 534 SUB-CONTRACTOR

12 DATA BOOTHS INSTALLATION NO’S 467 SUB-CONTRACTOR




13 ERECTION OF POLES 8/9 M NO’S 4983 SUB-CONTRACTOR

14 LAYING OF DUCT NO - 54 M 78140 SUB-CONTRACTOR

15 LAYING OF TRIPLE DUCT M 49050 SUB-CONTRACTOR

16 INSTALLATION SUB DUCT M 79084 SUB-CONTRACTOR

17 LAYING OF STEEL DUCT M 494 SUB-CONTRACTOR

18 ERECTION OF CONCRETE MARKER POSTS NO’S 838 SUB-CONTRACTOR

19 FIXING OF STAYS FOR POLES NO’S 1224 SUB-CONTRACTOR

20 LAYING OF FIBER OPTIC CABLE 48 F M 51531 SUB-CONTRACTOR



23 LAYING OF FIBER OPTIC INTERNAL CABLE M 965 SUB-CONTRACTOR

24 ERECTION OF AERIAL CABLE M 319143 SUB-CONTRACTOR




25 TRENCHING 1.5 M IN NORMAL SOIL M 21199 SUB-CONTRACTOR

26 TRENCHING 1.5 M IN ROCKY SOIL M 5328 SUB-CONTRACTOR

27 CONSTRUCTION OF MAN HOLE MRT 8 B NO 1 SUB-CONTRACTOR

28 CONSTRUCTION OF JOINTING CHAMBER JRC 12 R NO 35 SUB-CONTRACTOR

29 CONSTRUCTION OF JOINTING CHAMBER JRC 12 N NO 117 SUB-CONTRACTOR

30 CONSTRUCTION OF JOINTING CHAMBER JRC 14 R NO 27 SUB-CONTRACTOR

31 CONSTRUCTION OF JOINTING CHAMBER JRC 14 N NO 67 SUB-CONTRACTOR

32 TESTING OF SPARE DUCT M 36181 SUB-CONTRACTOR

33 SPLICING OF 48 F NO’S 16 SUB-CONTRACTOR





MAN POWER ESTIMATION

1. WLL Sites 89 sites x 3 team days =267 Team days2. SDH Sites 22 sites x 2 team days =44 Team days3. M/W Sites 20 sites x 2 team days =40 Team days4. Main P.S. sites 30 sites x 2 team days = 60 Team days5. Solar P.S. sites 53 sites x 3 team days =159 Team days

Total Team days = 570 Total working days =570 x 7/6=665

Team of 1 Engineer and 1 Technician may be required for a period of two years. But taking into account the following factors from Effective Date of contract (EDC):Post-bid survey and finalization of BOQ = 2 monthFinalization of suppliers and placing of orders =2 monthsLead time of suppliers = 4 monthsInland transportation to sites = 2 monthwe may require 2 teams if project is to be completed in 24 months time and 4 teams if it is to be completed in 18 months, including testing and commissioning.

Based on the above parameters Implementation Schedule is prepared, keeping in mind completion period of project from the Effective Date Of Contract (EDC).


PREPARATION OF BIDS(IMPLEMENTATION SCHEDULE)COMPLETION TIME ESTIMATION

SL.NO ACTIVITY 0 2 4 6 8 10 12 14 16 18 20 22 24-----36

1. SURVEY & FINAL BOQ

2. APPROVALS

3. PLACING OF ORDERS

4. SUPPLY OF OFC

5. SUPPLY OF SDH EQUIPMENT

6. SUPPLY OF TOWERS

7. SUPPLY OF WLL EQUIPMENT

8. SUPPLY OF POWER PLANT

9. LAYING OFC & CIVIL WORKS

10. TOWER FOUNDATION WORKS

11. ERECTION OF SHELTERS

12. ERECTION OF FENCE & GATE

13. TOWER ERECTION

14. ANTENNA W/G HOISTING

15. INSTALLATION OF EQUIPMENT

16. TESTING & COMMISSIONING

17. HANDING OVER

18. WARRANTY



MANAGEMENT COST

S.NO. ACTIVITY UNIT QTY. M.MONTH T.M.MONTH U.R. (US$) AMOUNT (US$)

AA STAFF SALARY (SAY) P.D. NO. 1 12 12 1600 19,200.00

BB LOCAL TRAVELING (SAY) NO. 1 2 2 600 1,200.00

CC AIR FARE (TO/FRO) NO. 1 2 2 1500 3,000.00

DD PROJECT OFFICES PD (RENT) NO. 1 12 12 1000 12,000.00

EE PROJECT OFFICES STAFF (RENT) NO. 5 6 30 400 12,000.00

FF FURNISHING OF OFFICE PD NO 1 1 1 5000 5,000.00

GG FURNISHING OF OFFICE STAFF NO. 5 1 5 2000 10,000.00

HH VEHICLES (RUNNING AND MTCE) NO. 1 12 12 800 9,600.00

II TELEPHONE/FAX NO. 1 12 12 500 6,000.00

JJ TOOLS AND TACKLES NO 2 1 2 5000 10,000.00

KK HIRING OF STORES NO 5 6 30 200 6,000.00

LL FOREIGN TRAINING NO. 2 0.5 1 3000 3,000.00

MM ON THE JOB TRAINING NO. 1 1 1 2000 2,000.00

NN AS BUILT DRAWINGS SETS 12 1 12 200 2,400.00

GRAND TOTAL (US $)


PREPARATION OF BIDS(PROJECT ESTIMATE – BIDDING COST)

AN EXAMPLE - BUT FACTORS VARY

ACTUAL EXPENSES (A) SUPPLIES (US $) (B) SERVICES (US $) REMARKS

SUPPLY OF MATERIALS (CIF) SAY 15,000,000

COST OF WORKS BY SUB-CONTRACTOR WITH LOCAL ITEMS

50,000 2,000,000

MANAGEMENT COST SAY 1,000.000

TOTAL COST (US $) 15,050,000 3,000,000

ADD ON CONTINGENCIES 1.0 % 5.0 % UNFORESEEN

INTEREST 1.5 % 0.5 % PAYMENT TERMS

BANKING CHARGES 0.5 % 0.5 % L/C & OTHERS

ECGC 0.5 % 0.5 % TO BE ANTICIPATED

INSURANCE 1.0 % 1.0 % TO BE ANTICIPATED

GIFT/ENTERTAINMENTS 0.25 % 0.5 % TO BE ANTICIPATED

NEGOTIATION MARGIN 1.0 % 5.0 % TO BE ANTICIPATED

MARGIN 5.0 % 15 % TO BE ANTICIPATED

TOTAL % / MULTIPLYING FACTOR 11.75 % / 1.133 28.00 % / 1.39

TOTAL (US $) 17,051,650 4,170,000 GRAND TOTAL (US $) 21,221,650


POST-BID SURVEY & FINALIZATION OF B.O.Q.(CONTRACT NEGOTIATION AND SIGNING OF AN AGREEMENT)

1. In one stage bidding, client first goes through technical evaluation of all the received bids. Price bid is opened only, who qualify technically. Normally, work is awarded to the L-1.

2. In two stage bidding, first technical bids are only called, and technically evaluated. Commercial bids are called for from parties, who technically qualifies.

3. Letter of intent is given to the contractor and called for negotiation.4. During negotiations, the tender is reviewed and all clauses discussed.

Negotiation is very tough time for the contractor, where he has to see on what clauses he can agree to the terms of client.

5. Just after completion of negotiation, Contract Agreement is signed by both the parties.

6. Effective Date of Contract (EDC) comes into force as per terms of Contract Agreement.

7. Performance Bank Guarantees, Opening of L/C and Post-Bid Survey actions starts by both the parties.

8. Post-Bid survey is jointly done to confirm the Bill of Quantities (BOQ) of the Tender Document. Normally variation of ± 10 % of amount is O.K.


POST-BID SURVEY & FINALIZATION OF B.O.Q.(TECHNICAL SURVEY FOR LOS LINKS-SURVEY INSTRUMENTS)

1. Laptop or pocket computer2. Global positioning system (GPS)3. Digital or analogue THEODOLITE with compass as an

attachment4. Barometric altimeter 0.5 m resolution5. High resolution binoculars6. Camera7. WALKI-talkie 1.2 GHz RANGE8. WALKI-talkie vhf range9. Prismatic compass10. Mirrors (tailor made)


POST-BID SURVEY & FINALIZATION OF B.O.Q.(TECHNICAL SURVEY FOR LOS LINKS-SURVEY INSTRUMENTS)

11. Safety belts12. Measuring tape-50 m13. Measuring tape-5 m14. Polarized camera15. ROTRING scale 1:100, 125, 200, 250, 500, 75016. Leveling staff17. Magnifying glass18. Stationary items19. Topographical instruments20. Hammer and pegs


POST-BID SURVEY & FINALIZATION OF B.O.Q.(TECHNICAL SURVEY FOR LOS LINKS – GENERAL GUIDANCE)

Detailed Survey:1. Study thoroughly the tender document, its survey report and BOQ.2. The idea of post bid survey is to confirm BOQ along with the representatives of

client and get the approval of the client, which is normally through a consultant appointed by the client.

3. Pre-bid survey is normally done in a hurry either for lack of time on your own part or client just show the sites and moves ahead. Bidders don't get time to study the sites or terrain in detail.

4. After post-bid survey variations may be in Antenna heights, Tower Heights, Due to addition/deletion of Diversity Operation, quantities of Equipment/Power plant seizing may vary.

5. Detailed Survey may be carried out as already discussed, but technical survey sheet may be filled for each and every site, whether it is an existing site or it is new site.

6. Before going to the sites, thorough map study should be done, which is going to save lot of time in the field. Check from map study, the critical obstacle in each hop, which are to be visited in subsequent visit.


POST-BID SURVEY & FINALIZATION OF B.O.Q.(TECHNICAL SURVEY FOR LOS LINKS – SITE DETAILS)

Site Name: Link Name:Date of Visit: Engineer:1. General Information:• Access description: Nearest town: Distance:

Station access guide map/sketch:Number of photos taken with Identification and description:

• Location plan:Available information: Latitude: Longitude: Altitude:Site location indicated on map: Map reference and scale:Coordinates and altitude checked:

• Plot plan: acquired/to be acquired: proposed:Plot measurements and drawing/updating of plot plan:Soil condition: ordinary/rocky/sandy/clayey/stony/other:Terrain condition: flat/cultivated/bush/slope/other:Obstacles on plot: Number of photos taken:

• General Comments:accommodation/space for stores/if unattended etc.



Site Name: Link Name:Date of Visit: Engineer:2. Transmission Information:• Existing radio facilities:

Type:Capacity:Configuration:Facing:Power Tx:Frequency:Feeder type/length:Antenna type/size/height/polarization:

• Existing multiplex facilities:Type: Capacity: Block diagram:

• Foreground obstructions:facing azimuth height distance description

AB



Site Name: Link Name:

Date of Visit: Engineer:• Building: existing/non-existing height of ceiling• Radio room: existing/non-existing height of ceiling• Station layout: building/radio room/power room/solar power etc.• Available space for: radio/mux/power supply/solar power• Distance between radio room (mux) and exchange room (MDF):• Distance between batteries and rectifiers:• Distance between rectifier and AC distribution board:• Distance between radio and DC distribution board:• Distance between tower and radio room• Internal cable ladder:• Waveguide/feeder cable length:• Distance between microwave station and exchange:• Tower Earthing: Fence: Site layout:



Circular site layout indicate

Approx. building and

Tower position,

Beam directions,

Compass

North bearing

And mast

Fixing points.

Equipment room

PowerRoom

100 M Tower

North



Site Name: Link Name:Date of Visit: Engineer:3. Civil works information:• Access road: Existing/non-existing Suitable/non-suitable

improvement required: Number of photos taken:• Interference along the path: yes/no• Distance and direction to: i) main road/highway ii) power line

iii) airport• Electrical soil resistivity:• Excavation works required:• Leveling works required:• Vegetation to be removed:• Blasting works required:• Type of drainage:• Availability of water source:• Number of photos taken:




Date of Visit: Engineer:

4. Tower Information:• Tower if existing: Type:- SS/mast, Tubular/angle, height.

Condition of:- steelworks/painting/foundation etc.• Platform number: measured height:

Antenna type size direction azimuth

• Waveguide/transmission line bridge drawing; Availability of space for additional Tx lines and Tx line entry glands.

• Tower new: Proposed location, Soil bearing: kg/sq.cm• Terrain inclination: excavation required/blasting required• Number of photos taken.




Date of Visit: Engineer:

5. Power Supply Information: station existing• Primary AC: available/not available nominal voltage fluctuation• Diesel Generator: type/voltage/frequency/capacity/configuration• DC power: Rectifier/charger:- type/voltage/capacity

Batteries:- type/voltage/capacity• Solar power: number of panels/types of panels/capacity

batteries:- type/voltage/capacity• Actual power consumption: AC/DC• Spare capacity available: AC/DC• Additional power supply requirement; AC/DC/Solar Power• Station not existing: Nearest AC distribution point:- voltage, frequency,

distance Km, type of connection, describe. • Number of photos taken:



NNNN A N



SL.

NO.

Ant. Direction

Ant. Azimuth.

Ant. Height.

Ant.

Type/Size

Ant.

Polarization.

W/G

Type

W/G

Length.

Eqp.

Branch.

Eqp.

Model.

Eqp.

Out

Put

Power.

Eqp.

Tx

Freq.

Eqp.

Rx

Freq.

Eqp.

System.

Remarks.


POST-BID SURVEY & FINALIZATION OF B.O.Q.(TECHNICAL SURVEY FOR OFC LINKS – SITE DETAILS)

Items Required for Route Survey of OFC Links:1. Rodometer2. Compass3. Survey /Geographical/Tourist maps4. Camera5. Level with staff6. Digital Multi meter7. Calculator8. Measuring Tape 30 M9. Measuring Tape 3 or 5 M10. Safety shoes11. Torch12. Hat/cap13. Umbrella/raincoat14. Floor marking tape/Permanent Marker pen



Route Index Diagram: Route is invariably fixed by the client is part of the tender document. Survey team has to carry out detailed measurements of the cable route and prepare Route Index Diagram (RID). Following points are to be decided/recorded in the RID and also brought out in tabular formatting.

1. Width with Km readings of rail/road crossings (road cutting), bridges, culverts, streams/rivers (dry/flowing), water logging areas etc.

2. Probable location of joint boxes, terminations and repeaters.3. Bending of roads, location of manholes/hand holes. This is to decide max. lengths

of fiber which can be pulled in one stretch. Normally it is 200-250 m and at bends.4. Width of high way, boundary of road with high way description.5. Surroundings, land scape, pits, slopes etc.6. Type of soil to be excavated for trenching.7. Km marks, important buildings enroute e.g. school, hospitals, petrol pumps,

workshops, branching out of roads etc.8. City area and area jurisdiction of different concerned authorities.9. In case site is existing, site details and site lay out plan to be prepared.



Site Survey: This is for the existing sites available on the proposed route.1. Precise location of the site with approach road sketch.2. Contact details of the site in charge.3. Existing lay out plan to be obtained (if available).4. Lay out plan of equipment room, power plant rooms and checking the

availability of space for new equipment and power plant.5. Marking of the proposed equipment.6. Study of the existing power plant which is likely to drive the proposed

equipment.7. Earthing arrangement.8. Cable entry and routing within the building. 9. Study of exchange interface.10. Ready For Installations (RFI) action points to be noted for advance action

of the client in case work is awarded to your company and will be useful during post-bid survey.



1. Site Name: Date of survey:• Site condition: Existing /New• Nearest land mark: Its distance from site:• Approach road: Describe:• Building: House/shelter etc.• Equipment room location:• Availability of storage space:• Management: Manned/unmanned• Water supply: Available or not, nearest source• Site address:• Site contact person: Contact no’s• Remarks about the site:2. Site location lay out plan: To be drawn if not available



3. Equipment room:• Station layout: Available/drawn sketch enclosed• Building/room lay out: Available/drawn sketch enclosed• Flooring: Concrete/false/others• Ceiling height (> 3 M): Describe if any problem at proposed location.• False ceiling: Yes/no• Equipment location: Marked/not marked

4. Cable and runway:• Existing cable routing: OH/underground/trench/others• Proposed cable: Describe proposed route/routing• Cable runway length:• Wall opening location:• Cable length to DDF:• DDF interface for E1: Towards exchange 75 / 120 ohm• Cable length to FDF• Power cable length:



5. Optical fiber cable:• Cable vault/chamber: Yes/no, length• OFC entry in the building: Describe• Nearest manhole/hand hole: Distance6. Room environment:• Dust free: Yes/no• Illumination: Good/inadequate/non• Air conditioning: Yes/yes but inadequate/non• Air conditioning capacity: Existing if any/ proposed requirement7. Power supply:• A/C mains availability: If yes % time availability

Back up generator set: If available, describe details• DC -48V DC-1 -48V DC-2 (back up)

Existing yes/no/inadequate yes/no/inadequatePlant capacity (A)Present Load (A)Spare Capacity (A)Required Capacity (A)Battery capacity (AH)



• DC PDB: If existing, power cable length from equipment rack

spare capacity. If new, mark proposed location.• A/C Sockets: No’s available in the room with rating (5A/15A)

8. Earthing: Existing, value

Soil type: Soft/soft rock/hard rock (for new pit)

Earthing cable length and size:

9. Synchronous clock:• Status: Existing/non existing• Extracted from:• Cable length:

10. General data: Temperature Max/min

11. Remarks: Describe

12. Clients action items for site Ready For Installation (RFI): Describe all the points for which action is required by the client.

13. Enclosures:


POST-BID SURVEY & FINALIZATION OF B.O.Q.(POST SURVEY ACTIVITIES)

1. Detailed survey for LOS and OFC links to be completed as already discussed and go through report generation process to make a comprehensive report.

2. Make necessary changes in BOQ of tender document and submit to the client/consultant for approval.

3. Once approved, orders can be placed with vendors for different items.

4. Works which are not related to the supplies can be executed.5. Project time schedule and execution activities are reviewed from

time to time and critical activities watched minutely to see, that, implementation schedule is not slipping.

6. In case, there is delay due to some unavoidable circumstances, additional teams may have to be deployed to adhere to the implementation schedule.



CONCLUSION: The course has been developed with the objective, that, Engineers come out of colleges with more theoretical knowledge and are not aware of actual field problems. Pre-bid survey is must for every globally floated tender, this not only help the bidder to finalize the BOQ but also he get the feel of that country for finalizing his add on’s. International Exposure experienced during last 20 years on similar assignments have been shared.



Tick (√) on one’s

1. (a) Free space loss increases if frequency is increased and decreases if distance is increased.

(b) Free space loss decreases with the increase of both distance and frequency.

(c) Free space loss increases with the increase of both distance and frequency.

2. (a) First Fresnel Zone Radius increases with increase in distance and decreases with increase in frequency.

(b) First Fresnel Zone Radius decreases with increase in distance and increases with increase in frequency.

(c) First Fresnel Zone Radius decreases both with the with increase in distance and in frequency.

3. For standard atmosphere value of K is: (a) K=1 (b) K=4/3 (c) K=2/3

4. In a hop Earth Bulge is maximum at (a) the ends (b) the center (c) the critical obstructed point.

5. Reflection point area lies between a K factor of: (a) K=1 and K=Infinity.

(b) K=4/3 and K=2/3 (c) K=7/6 and K=5/12.



6. For a hop if all other parameters are kept same, for K=4/3 tower height will be (a) less (b) more (c) equal in comparison with K=2/3.

7. If frequency diversity is used, the separation between two frequencies is generally kept (a) 12-20 % (b) 2-3% (c) 5-10%.

8. Separation between Space Diversity antenna’s is to the tune of:(a) 100-200 λ (b) 5-10 λ (c) 20-40 λ.

9. CCIR defines availability of radio relay links over hypothetical reference circuit of 2500 Km route as (a) 97.9 % (b) 79.7 % (c) 99.7 %.

10. India is located between following co-ordinates:(a) Latitude 8 º - 36 º N, Longitude 68 º - 96 º E(b) Latitude 8 º - 36 º S, Longitude 68 º - 96 º W(c) Latitude 8 º - 36 º N, Longitude 68 º - 96 º W

11. Azimuthal angles or bearing is measured from:(a) True South (b) True North (c) True East

12. Maximum height of line of sight towers is normally limited to:(a) 200 M (b) 300 M (c) 100 M



13. Reliability of a LOS hop can be improved by:

(a) Space Diversity (b) Increasing the hop distance (c) Decreasing tower height.

14. On a straight link when single frequency is used in tandem, normally change of polarization is recommended every: (a) 3rd hop (b) hop (c) 5th hop.

15. Optical cable systems compared to Line of sight links have:

(a) Smaller band width (b) Equal band width (c) large band width.

16. For communication purposes OFC uses following material:

(a) Silicon (b) Glass (c) Germanium.

17. In fiber optic systems fade margin of following values is considered as adequate:

(a) 30 -40 dB (b) 3 – 5 dB (c) 20-30 dB.

Engineering

1 survey system design_and_engg