Rate-Compatible Non-Binary LDPC Codes for Rate Adaptive Systems

摘要

Nowadays, adaptive wireless systems employ various modulation schemes and several pairs of encoders and decoders in order to increase the overall performance. We propose in this paper an adaptive system which employs a single combination of a higher modulation scheme and a channel code. The main idea is to utilize a rate-compatible non-binary LDPC code as the channel code. The adaptability of system is easily obtained just by adjusting the coding rate of the rate-compatible code. We use multiplicative repetition and puncturing by recoverable step to obtain good rate-compatible non-binary LDPC codes. The proposed system exhibits good decoding per­formances over a wide range of bandwidth efficiency. For moderate information length, proposed proposed system performs within less than 1.5 dB from the theoretical limit in low SNR regime.