LINK BUDGET CALCULATIONS

A. CONDITIONS FOR PUTTING UP A MICROWAVE LINK

Minimum Path length from site A – B: 20 miles actual length: 22.57 miles

Minimum Path length from site B – C: 10 miles actual length:11.31 miles

Reliability requirement: 99.9999%

B. TOPOGRAPHICAL SITE OF THE MAP

SCALE USED: 1:50,000

HOP 1:

HOP 2:

C. FREQUENCY PLANNING

For HOP A – B:

Frequency Band: 13 GHz 12.75 – 13.25 Ghz

Low Band Frequency Range: 12.75 – 12.984 GHz

Low band and High band frequency bandwidth = 0.234 Ghz/ 235 Mhz

High band frequency range = 13.016– 13.25 Ghz

Duplex distance = 266 mhz

Guard band = 20 mhz

Channel bandwidth = 14 Ghz 14.4 – 15.35

NUMBER OF CHANNELS = FREQUENCY RANGEBANDWIDTH

CHANNELBANDWIDTH = 234/14 = 16.78 or 17 channels.

choose an arbitrary channel not greater than 17 (6)

14Mhz x 6 = 84 Mhz

Low transmit frequency: 12.75 Ghz + .084 Ghz = 12.834 Ghz

High transmit frequency: 13.015 Ghz + .084 Ghz = 13.099 Ghz

For HOP B – C:

Frequency Band: 13 GHz 12.75 – 13.25 Ghz

Low Band Frequency Range: 12.75 – 12.984 GHz

Low band and High band frequency bandwidth = 0.234 Ghz/ 235 Mhz

High band frequency range = 13.016– 13.25 Ghz

Duplex distance = 266 mhz

Guard band = 20 mhz

Channel bandwidth = 14 Ghz 14.4 – 15.35

NUMBER OF CHANNELS = FREQUENCY RANGEBANDWIDTH

CHANNELBANDWIDTH = 234/14 = 16.78 or 17 channels.

choose an arbitrary channel not greater than 17 (6)

14Mhz x 6 = 84 Mhz

Low transmit frequency: 12.75 Ghz + .084 Ghz = 12.834 Ghz

High transmit frequency: 13.015 Ghz + .084 Ghz = 13.099 Ghz

AZIMUTH COMPUTATION

Formula:

Azimuth=cos−1sin ( latitudeB )−sin (latitude A)cos (D)

cos (latitude A ) sind(D)

D=cos−1 ¿¿

Latitude LongitudeSite A 14.9941 120.7550Site B 14.7656 120.9998Site C 14.9289 120.9771

AzimuthSite A – Site B 133.970936 / 133°58′15.37″Site B – Site C 350.627488 / 350°37′38.96″

Site A – Site C 107.001861 / 107°0′6.7″

D. FREE SPACE LOSS

FROM A- BFSL = 96.6 + 20 log (fGHz) (D)

LBF: FSL = 96.6 + 20 log (12.834) (22.57)

= 145.84 dB

HBF: FSL = 96.6 + 20 log (13.099) (22.57)

= 146.02 dB

FROM B – C

FSL = 96.6 + 20 log (fGHz) (D)

LBF: FSL = 96.6 + 20 log ((14.484) (11.31))

= 140.88 dB

HBF: FSL = 96.6 + 20 log ((15.128) (11.31))

= 141.26 dB

Antenna height = Ha = D2

8+43.3√ D

4 f

Antenna in feet Antenna metersHa – B 92.38623 28.159Hb - A 92.09434 28.0703Hb – C 92.38623 28.159Hc - D 92.09434 28.0703

E. RECEIVED SIGNAL LEVEL

Tx Connector loss

( transmitter antennaheight100

+2) x 0.15 (from spec sheet)

Tx Waveguide loss

(transmitter antenna height x5.25100 )+waveguide insert los s

Rx Connector loss

( receiver antenna height100

+2) x 0.15 (from spec sheet)

Rx Waveguide loss

(Receiver antennaheight x5.25100 )+waveguideinsert los s

From A – B

Output powerTx connector loss 0.3Tx waveguide loss

Tx gainRx gain

Rx connector lossRX waveguide loss

FSL