The spectrum plot image below shows two carriers between two 1.8m Ky band earth station antennas.
The plot was made using a 70 MHz IF monitor point on the output of the Ku band to 50-90 MHz down-converters.
The satellite transponder used had uplink and downlink Ku band beams covering of all Europe, connected back on itself so that all sites could see all their own transmissions and all the others.
The corresponding link budget is at link budget for SCPC point to point voice calls using 1.8 VSAT dishes
Each carrier had a customer information data rate of 9.6 kbit/s and carried one direction of a G729 voice call.
The FEC coding was rate 1/2 and the modulation QPSK. Transmission rate was 19.3 kbit/s. Symbol rate was 9.6 ksps.
The power transmitted (VSAT TX BUC output power) for each carrier was 0.06 Watts. Try setting this in the link budget mentioned above.
Any problems or comments please e-mail Eric Johnston
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