面向星地通信的低复杂度通用编译码技术

摘要：面向高动态、大尺度变化的低轨星地链路，具有强大纠错能力的速率兼容（RC）信道编码方案对保障星地时敏业务的信息时效性是至关重要的。提出了一种适用于任意短线性分组码的新型译码思想，称为基于翻转重量的阶序统计译码（FWB-OSD）。FWB-OSD可以达到比传统译码算法更优秀的误码性能水平。在此基础上，针对3GPP标准低密度奇偶校验（LDPC）码的速率兼容编码方案，提出了一种将迭代译码算法与FWB-OSD进行级联的译码算法，称为多层置信组合译码（MBCD）算法。相比于现有置信传播（BP）及级联译码算法，所提MBCD算法在短码长LDPC编码方案下能够展现更优的译码性能。最后，基于星地信道模拟器及相关前端信号处理方法，在桌面端开发了所提编译码方案在星地链路下的半实物验证系统。

关键词：低轨星地链路；速率兼容信道编码；翻转重量辅助；多层置信；译码性能

Abstract: In the context of low-orbit satellite-ground communication, where both dynamic and large-scale changes are prevalent, the deployment of a rate compatible (RC) channel coding scheme with robust error correction capabilities is of paramount importance for the timely delivery of services. In this paper, an idea of flipping weight-aided ordered statistics decoding (FWB-OSD) for arbitrary short linear block codes is proposed, which can achieve superior error performance compared to traditional decoding algorithms. On this basis, a novel decoding algorithm is proposed for RC 3GPP LDPC coding schemes, which cascades belief propagation (BP) and FWB-OSD, called multi-belief combination decoder (MBCD). In comparison to the existing BP decoder and cascade decoder, the proposed MBCD performs better decoding performances in terms of block error rate (BLER). Finally, based on the land mobile satellite channel simulator and signal processing algorithms, a hardware-in-the-loop verification system for the proposed encoding/decoding schemes under the satellite-ground link is developed on the desktop.

Keywords:

low-orbit satellite-ground link; rate-compatible channel coding; flipping weight-aided ordered statistics decoding; multi belief; decoding performances