基于提前停止判决的编码软信息辅助载波同步

 针对目前编码辅助载波同步算法中复杂度较高、延时大的问题,提出了引入辅助停止判决机制的编码辅助载波同步算法。在现有的编码辅助载波同步结构基础上,该算法能对环路信噪比(SNR)进行实时判定,在环路SNR满足限定条件后提前停止编码辅助载波同步迭代,而不影响译码性能。采用新的相位估计方式估计含相位噪声的载波相位,提升了该条件下的环路信噪比。仿真采用码率为1/2的低密度奇偶校验(LDPC)码作为编码方式,结果表明:在误码率为10^-5时,该算法减少了约50%的编码辅助载波同步迭代次数;在含相位噪声的信号条件下,与理想解调译码相比,性能损失不超过0.15 dB。

Code-aided Carrier Synchronization via Soft Decision Feedback Based on Early Stopping Criterion

In order to solve the high complexity and high latency problem in current code-aided carrier synchronization scheme,a new code-aided carrier synchronization scheme which induces an early stopping mechanism is proposed.On the basis of the existing code-aided carrier synchronization structure,the proposed scheme makes decision of the loop signal to noise ratio(SNR) on the fly.The code-aided carrier synchronization will stop after the loop SNR exceeds a predetermined criterion with no performance degradation.With the improved phase estimation method,a carrier signal phase with phase noise can be estimated while the loop SNR also increases.Using 1/2 low density parity check(LDPC) code in simulation,the results show that the number of iteration in the proposed code-aided carrier synchronization decreases by about 50% when the bit error rate is 10-5;with phase noise signals,the performance degradation is less than 0.15 dB as compared with the ideal decoding performance.