부산대학교 도서관

A structure for decision feedback equalization (DFE) with low density parity code (LDPC) decoding is introduced for anti-multipath communication over underwater acoustic channels. The decoding performance of irregular LDPC codes is investigated. Simulations show that the DFE-LDPC structure has excellent anti-multipath performance. The BER (Bit Error Rate) of the system is less than 105, and the SNR (Signal to Noise rate) is higher than 11dB over three different underwater acoustic channels. Furthermore, the irregular LDPC codes optimized on AWGN channels are also excellent on strong multipath underwater acoustic channels. Under the same code rate and block length, irregular LDPC codes are better by about 0.5dB than regular LDPC codes with column weight 3 at BER=105.