Modified BP decoding algorithm for satellite communication

For regenerative transfer satellite communication system which uses LDPC code, Receivers suffer a bad decoding performance because of failing to estimate the channel correctly. It proposes a satellite communication system model and modifies traditional belief propagation decoding algorithm based on logarithm likelihood ratio. By using proper initial logarithm likelihood ratio, the system gets a lower total bit error rate. When the bit error rate is 10 -5 , the modified decoding algorithm offer 0.4 dB encoding gain.