北斗卫星导航系统多进制LDPC编码性能评估

Due to the long transmission distance and low power, satellite navigation receivers may not be able to demodulate the message normally in the complex environment. Error correction encodings were commonly used in the navigation message design to improve demodulation performance. With the improvement of technology, more powerful error-correction codes have been adopted in the modernization of GNSS (global navigation satellite system). BDS (BeiDou navigation satellite system ) new signals will adopt M-ary LDPC (low density parity check) encoding. Based on the principle of M-ary LDPC codes, the software simulation and hardware test results of M-ary LDPC codes on BDS were presented. Results show that the 64-ary LDPC codes have high coding gain, and they can outperform about 0.4~0.8 dB over their binary counterparts, which will greatly improve the demodulation performance under harsh environment. The results can provide reference for the development of BDS new receivers.