PART 2Network PlanningNEC Corporation

CONTENTS1. Check customers requirements2. Establish performance objective3. Determine frequency allocation plan4. Select equipment5. Link budget analysis

1. Check customers requirements

What Is the Business Requirement?What do we need to know before network design? Traffic volume, system capacity Transmission data speed Performance objectiveavailability and reliability Installed locations-- economics Scalability Network and System management InteroperatityCUSTOMERS REQUIREMENTS

2. Establish performance objective

Microwave links2.28MICROWAVE QUALITY:ERROR PERFORMANCE & AVAILABILITY The error performance events defined areES (Errored second): a one second period during which one or more EBs (errored block) occurs. SES (Severely errored second): a one second period during which 30% or more of EBs occurs. BBE (Background block error): an errored block not occurring as part of SES.Error performance parameters defined are: severely errored second ratio (SESR), background block errored ratio (BBER), and errored second ratio (ESR).

It is generally agreed that SER and BBER will also be satisfied once SESR meets the objective. Error Performance objective-suggested evaluation period 1 month

Quality of Microwave link--Error Performance objective

ITU-T G.826

Long haul

Rate(Mbps)

1.5 to 5

5 to 15

15 to 55

55 to 160

160 to 3500

Severely errored second ratio (SESR)

0.002 ( A

0.002 ( A

0.002 ( A

0.002 ( A

0.002 ( A

where A = (A1 + 0.01) Llink / 500for 50 km Llink 500 km

A = A1 + 2 ( 10-5 Llinkfor Llink > 500 km

A1 is provisionally been agreed to be in the range of 1% to 2%.

Short haul

Rate(Mbps)

1.5 to 5

5 to 15

15 to 55

55 to 160

160 to 3500

Severely errored second ratio (SESR)

0.002 ( B

0.002 ( B

0.002 ( B

0.002 ( B

0.002 ( B

Where B is provisionally been agreed to be in the range of 7.5% to 8.5%. B = 0.075 is used unless otherwise specified by the customer.

Access

Rate(Mbps)

1.5 to 5

5 to 15

15 to 55

55 to 160

160 to 3500

Severely errored second ratio (SESR)

0.002 ( C

0.002 ( C

0.002 ( C

0.002 ( C

0.002 ( C

Where C is provisionally been agreed to be in the range of 7.5% to 8.5%. C = 0.075 is used unless otherwise specified by the customer.

For example,

error performance objective for SDH (155 Mbps, link: 50 km) = 0.002 (0.01 + 0.01) 50 / 500 60 60 24 30 = 10 sec/month.A path fails to satisfy this Recommendation if any parameter exceeds the allocated objective in either direction at the end of the given evaluation period.

The suggested evaluation period is 1 month.

Availablilty-suggested evaluation period 1 month

Availability is the ratio of the time that the link is available to the total time.The availability objective is defined as follows. AR = 1- (Bj Llink / LR + Cj) where j: section of national portion, j = {1 = access network, 2 = short haul, 3 = long haul} LR: reference length = 2500 km. The lower limit of Llink used to scale the objectives is Lmin = 50 km.

For example, availability objective forSDH (155 Mbps, link: 50 km) = 1 (1.9 10-3 50 / 2500 + 1.1 10-4) = 0.999852. Therefore, unavailability = (1-0.999852) 60 + 24 365 = 77 min/year.

Access portionShort-haul portionLong-haul portionB1C1B2C2B3C305 10-404 10-43 10-3 for 250Llink

3. Determine frequency allocation plan

Choose a range of frequencies with appropriate radio characteristics that meet the needs of your application according to the electromagnetic spectrum table specified by the local radio agency. Selection criterion:1) The signal at lower frequency propagates longer distance. For example, 4GHz signal may reach as far as 100 km, while 38 GHz is good for about 5 km. 2) Low frequency is more apt to interfere neighboring areas. 3) Higher frequency can achieve higher antenna gain. 4) Higher frequency has smaller Fresnel zone and thus require less clearance over obstacles to avoid diffraction losses. 5) Higher bands have more bandwidth available for high-speed data, and less probability of interference. Check local radio-governmental regulation about frequencyITU-R Recommdendation for microwave frequecy band:

Band4GL6GU6G7G8G11G13G15G18G23G26G38GScale3.6~4.25.9~6.46.4~7.17.1~7.77.7~8.510.7~11.712.7~13.214.5~15.317.7~19.721.1~23.624.5~26.537.0~39.5

More details:

The various frequency characteristics are discussed as follows. 1) 7.125 8.5 GHz : low frequency is susceptible to multipath fading

2) 17.7 GHz 19.7 GHz : 18GHz band is a general-purpose point-to-point microwave band, used mostly for shorter links (less than 20 km).

3) 21.2 23.6 GHz : 23 GHz band is a general-purpose point-to-point band which suffers additional (and variable) signal attenuation from water vapor, which limits its use to relatively short path lengths.

4) 27.5 GHz 29.5 GHz: 28 GHz is most susceptible to rain effect. 5) 37.0 GHz 39.5 GHz: At 38 GHz, there is a window of resonant absorption by water vapor, and can be used for communication.

4. Select equipment

Menu

NECs PP Microwave Radio Systems

-

Series/ModelSystemModulationFrequencyInterface4GL6U67G8G11G13G15G18G23G26G28G32G38G52/55/58G

PASOLINKV3/V4PDH4PSK2,4,8,16x2MB1x34MB10/100Base-T(X)

MxPDH4PSK/16QAMselectable5,10,20,40x2MB10/100Base-T(X)

PASOLINK+PDH16QAM8, 16x2MB

SDH(STM-0)32QAM21x2MBSTM-1(P.F)

SDH(STM-1)32MLCMSTM-1/OC310/100Base-T(X)

SDH(STM-1)128QAMSTM-1/OC310/100Base-T(X)

SDH(2xSTM-1)128QAM/ XPICSTM-1/OC310/100Base-T(X)

3000S3000S(STM-1)64MLCMSTM-1OC3

128MLCMSTM-1OC3

STM-1(Single Fiber)--

TX1.3 RX1.5

TX1.5 RX1.3BT

X.21--

STB

10/100Base-T--

10Base-T2MB

100Base-TSTM-1

34/45MB--

3x45MB--

CHspace

Point to Point Access Radio

Channel Spacing vs Capacvity

Spacing(MHz)

Series/ModelSystemModulation/FEC3.5713.5/1427.5/28/29.654050/55/56/60

PASOLINK4PSKPDH4PSK2x2MB4x2MB8x2MB16x2MB------

PASOLINK16QAMPDH16QAM+RS4x2MB8x2MB16x2MB---------

Sub STM-016QAMPDH16QAM+RS4x2MB8x2MB16x2MB---------

STM-032QAMSDH32MLCM------21x2MB(52MB)---------

STM-132QAMSDH32MLCM+RS---------------155MB

STM-0128QAMSDH32MLCM---------155MB155MB---

Sheet2

Sheet3

Choose the right equipments depending on required capacity

Outline of PASOLINK0.6m AntennaOutdoor unit(ODU)Installation poleIndoor unit(IDU)

Outline of PASO+0.3m AntennaOutdoor unit(ODU)Installation poleIndoor unit(IDU)

ODUIDU(1+1)Pasolink Mx ODU & IDUSame size as V4IDU(1+0)2U1U

NEC SDH 3000S 3+1 SYSTEM

SDH Application2 MBMUXMICMICMUXMUX2 MB. . . . MUX[FOTS]MUXMUX2 MB2 MB2MB[FOTS]. . . . . . . . . . . .. . . . . .. . . . . . STM-1 in series SYSTEM[Terminal][UP/DOWN][Relay]Fiber circuit protectedMICMICMICMICMICMICMICMICMICMIC

MSC : Mobile Switchover CenterBSC : BTS ControllerBTS : Basic Transmitting SystemBSCMSCPSTNBSC.....MSC2000SBSCBSCBTSBTSBTSBTSBTSBTSBTSBTSBTSBTSBTSBTSBTSBTSBTSBTSBTSBTSBTSBTSBTSBTSBTSBTSBTSBTSPASOLINKPASOLINKBTSPASOLINK2500S/2000S2500S/2000S2500S/2000S2500S/2000SConfiguration in mobile network

BSCPSTNBSCBSCBTSBTSBTSBTSBTSBTSBTSBTSBTSBTSBTSBTSPasolinkPasolinkBTSPasolinkBSCBTSBTSBTSBTSBTSBTSPasolinkPASO-SPASO-SPASO-SPASO-SMSCConfiguration in mobile network

PASOLINK MX APPLICATION

Types of Mobile Backhaul Network

Mobile celluar Plan of London(downtown)

P-P Microwave ApplicationAreadowntownM25countrysidemotorwayMSC-MSCApplicable systemRadius of cell100m~1km1~5km5km ~serialrelayPasolink 38GHzPasolink 15~38GhzPasolink 8~23GHzPasolink 2*2~16*2MB2500S 34MB2500S 4*2~16*2MB2000S 140MB/ STM-12000S 140MB/STM-1

Network configuration-One Hop system

Network configuration-Multi- Hop system

ADM

Back to Back

Remote Site A

Remote Site B

Remote Site C

Remote Site D

Network configuration-Ring system

Network configuration-Multi-branch system

5. Link budget analysis

Path Clearance CriteriaH1 : Antenna elevation at site A(above sea lever:m) h1= h3h4 h2 : Antenna elevation at site B(above sea level:m) h2= h5h6 H3 : Antenna elevation at site A(from the ground:m) h4 : Site elevation at site A(above sea level:m) H5 : Antenna elevation at site B(from the ground:m) h6 : Site elevation at site B(above sea level:m) hS : Ridge elevation(above sea level:m) hC Path clearance at ridge point(m) d1 : Distance of near end of path(m) d2 Distance of far end of path(m) d : Total distance per hop(m)

1 Path clearance at ridge point:hc

rActual earth radius 6.37106m kEffective earth radius coefficient2 Radius of first fresnal zone (m)

wave lengthm3 Path clearance margin: hcm (m)

hcm should be bigger than zero to obtain the necessary clearance margin.4 Clearance criteria -For main antenna a. Radio Frequency less than 7GHz b. Radio Frequency more than 7GHz 1.0F at K=4/3 1.0F at K4/3 0.4F at K2/3 (When flat terrain) 0.577F at K2/3 (When flat terrain) 0F at K2/3 (When obstacle is ridge) 0F at K2/3 (When obstacle is ridge) 0.3F at K2/3 (When obstacle is not ridge) 0.3F at K2/3 (When obstacle is not ridge)

Microwave links2.06CLEARANCEClearance rulesa) 1st Fresnel ellipsoid fully free forb) Direct ray between antennas not stopped by geographical relief for K minimum value (K depends of the local climatic conditions and hop length) 43K =N Refractive indexgradient1 st Fresnel ellipsoidal RxTxTx'Virtual earthRoReal earthRAMB(AM+MB-AB = /2)Fresnel zone(possible reflection)

Microwave links2.18LINK BUDGET

Lfs = 96.6 + 20*log10 F + 20* log10 DLfs = free space loss in dBF = frequency in GHzD = path length, in milesorLfs = 32.4 + 20*log10 F + 20* log10 DLfs = free space loss in dBF = frequency (GHz)D = path length, in kilometers Link Budget AnalysisFade MarginFlat fade margin = Receive signal level Receiver sensibility threshold Receiver Signal Level = Ptx Ltx + Gtx Lfs + Grx LrxPtx: transmitter output powerLfs: free space path lossGtx: transmitter antenna gainGrx: receiver antenna gainLtx: transmitter feeder lossLrx: receiver feeder loss

PRe=Equivalent Rayleigh fading occurrence factor F1=Fading margin Link Budget AnalysisUnavailability FFrequency in GHz dhop distance in km KQB and C are given below. Reeffective reflection coefficient PRe=

STM-1, 18G, Rain=28mm/h, Antenna=60cm

0

0.0005

0.001

0.0015

0.002

0.0025

0.003

1

2

3

4

5

6

7

8

9

10

Hop Length (km)

Unavailability (%)

128Q

32Q

Enter Customer DataDoes calculated clearance satisfy specification?Calculate Fade marginCalculate unavailabilityDoes availability meet customers requirement?

Required data rateDesired BERHop lengthFrequencyAdjust antenna heightInstall repeater stationsCalculate Path lossModify antenna diameter,frequency band, or distance between hopsPath profileCalculate Receiver input levelNoYesNoYesBOQ

Serial long line trunk network is a main application of SDH radio.The system is constructed by - Terminal station - Regenerative repeater station - Add / Drop stationTandem connection to FOTS (Fiber Optics Transmission System) is available.A backup system for FOTS is also an important application.