RS-CR与RS-Turbo两类级联码的结构与性能分析

如果采用随机交织器和迭代的最大后验概率译码算法,Turbo码的译码性能接近Shannon限。但是当误比特率(BER)≤10-5时,性能曲线下降缓慢,趋近于水平线,影响了Turbo码的推广与应用。级联RS码能够有效地改善这一现象,但是RS Turbo级联码结构复杂,译码时延大。因此,本文基于交错与级联的思想,提出了一种新型的前向纠错码,即RS CR码(RS 复转码),设计构造了该码的编译码算法。RS码和复数旋转码同时对信息元进行编码,级联后新产生的二维前向纠错码,编码时间短,译码速度快,纠错能力可调,尤其适用于自适应的差错控制系统。

Analysis on Structure and Performance of RS-CR and RS-Turbo Codes

Turbo codes can approach the Shannon bound with the random interleaver and iterative maximum-a-posteriori probability decoders. But the "error floor" is observed by simulations with the Turbo code. It is not easy to improve the reliability of the Turbo code at BERs below 10~(-5). Based on interlace and concatenation, a new class of error-correct codes over two-dimension, the RS-Complex Rotary codes ( RS-CR codes ), are proposed. The encoding structure and decoding algorithms are designed. The Reed-Solomon codes and Complex Rotary codes are encoded in parallel. The time of encoding and decoding of RS-CRC is short. The decoding structure is simple. Because the error-correct capability of RS-CR Codes can be adjusted, it is especially convenient to apply the RS-CR codes in the adaptive error control system.