Co-channel Interference in GSO High Throughput Multi-beam Satellite in Indonesia: Study Link Budget and Capacity Analysis

Current satellite technology has developed rapidly from traditional satellites to High Throughput Satellite (HTS) because it offers the advantages of multibeam antennas and reuse frequencies. Nevertheless, intersystem interference exists. This study discusses Co-Channel Interference (CCI) in the 4-reuse color scheme on an 8-beam GSO HTS with Ku-band frequencies in Indonesia. The analysis was conducted by analyzing the link budget and capacity before and after interference on the user communication side, forward downlink, and return uplink. The results of the link budget before CCI, Carrier to Noise ratio or C/N on Beam 1 to 8 ranging from 23.34 dB to 23.50 dB. And C/N on the return uplink is 18.74 dB to 19.07 dB. Then after interference, the Carrier to Noise plus Interference Ratio or C/(N+I) on the forward downlink produces 11.96 dB to 12.15 dB. While the return uplink produces C/(N+I) of 13.91 to 14.05 dB for Beam 1 to Beam 8. Because CCI decreases signal quality, the total capacity decreases where the forward downlink before interference produces 8.99 Gbps to 4.74 Gbps. The return uplink capacity of 7.09 Gbps due to interference becomes 5.27 Gbps. The purpose of further research recommendations is to analyze CCI on other reuse color schemes with a more significant number of beams and analyze appropriate mitigation techniques.