Question

A broadcaster transmits its program over a geosynchronous satellite. The uplink and downlink carrier frequencies are 14 GHz and 12 GHz, respectively. The distance from the satellite to the gateway and the the receiver can both be approximated as 36,000 km. Assume that the uplink (the Gateway) antenna has a gain of 40 dBi, the receiver on the satellite has an antenna with a gain of 20 dBi and a noise temperature of 3500 K. The video encoder’s rate is 5 Mbps. Modulation used is QPSK with a roll-off factor of 0.25. The downlink 18 0 = N Eb dB. Find the uplink transmitter power if the operator wants the packet loss probability be 10−8 . (12 Marks)

Answer 1

Ctiven tha :- A broad atlev -ancmils Pl Pojyam over Sllite Greosynchwonous C Sol -> -A Cawiey vengy Ona he dstana of Sadelele to Receiver approximated of 36000 km. heCotilite gaim 45 dB ant emna powe S ette Jain dBi Reaciver 5 dBi Noise emparature 250 Yolof-factor = o.25 Hone Codimy EYor Comtrol (a) -findhe Reguired Band withf The Lt rate i 3mbas Bit Rade 3MbPS bit 3 mbpc Numbe of bit 2 5 10 bps Band width Ctb550 Lps 85oLps /s (o.195 mbps/s) Pamd with : 219902.5,

(b) Uplinktiansmitler powe f-the operatoi wants Per -Hou -hen ome paekot Have no more EIRP ?gtvopic yansmission Powe EPP ective -Transmitt e loalt Comrie EIRP 10 loTamsmitHer power Pointi locs (b) Arlemn Tamsmi-t{e antena Tamsmittepower /Caie (pi/ I10 3) 50dBm Antemna Gain TYamsmitH er 4--5dBi EiRP 50+ 45 95 dB ERP 95dB