Satellite data distribution in video transponder band-edge using 512 Kb/s SQAM

The experimental results of a one-month system field trial using a 512 kb/s superposed quadrature amplitude modulation (SQAM) satellite transceiver are described. The impact of cochannel and adjacent channel interference on the computer-simulated and measured performance of the band-edge system is investigated, and the corresponding bit error rate (BER) is analyzed. As an example application, International Datacasting Corporation´s digital audio broadcasting system is discussed. The dispersed spectrum of the video carrier interference is found to be sufficiently low in power to allow high-performance band-edge data transmission with excellent BER. The data link provided 99.8% error-free minutes over a 24-h broadcasting period with degradation to neither video picture quality nor to subcarrier services. Close to compact disc quality digital audio was delivered