Study On The Channel Coding And Decoding Technology In Maritime Digital Communication

Because the complex maritime communication environments easily lead to the communication errors, so it is necessary to implement the error control for the maritime communication, and the channel coding is one effective way to correct the errors. In this paper, firstly the maritime channel characteristics such as fading and interference are analyzed and studied. The fading includes the small-scale fading and the large-scale fading, and the small-scale fading is emphasized, especially the multipath fading. Interference mainly includes broadband, narrowband and pulse interferences, and their characteristics are studied and also their influence on the bit error rate is analyzed. Secondly, a variety of channel coding methods are studied, mainly including the RS code, convolution code, interweaver technology and LDPC code. Moreover, some relevant theoretical knowledge and algorithms of coding and decoding to the simulation effect graph, the influence of various parameters of the codes on their performances are analyzed, helpful to accurately and visually know each code’s performance. A more in-depth study of LDPC code is conducted, and an algorithm combining a lower triangular structure and the PEG algorithm to construct LDPC codes is proposed, to make the LDPC coding less complicated, but with the performance comparable with a randomly constructed LDPC. Finally, channel coding is stimulated in the maritime communications channel, namely, under a good sea state and only with thermal noise, under the situation of bursting noise and a bad sea state with other noise interferences, the RS code, the RS code and the convolution code and LDPC code, thus to get the performance of every code in the specific channel.