利用固定字段的自同步加扰系统容错译码

香农指出,信源中的冗余可以在接收端被用来提高系统性能。固定字段可以看作是信源中的冗余。本文研究自同步加扰系统信源固定字段利用问题,提出由去扰数据进行固定字段检测,得出错误位置,并进一步映射为去扰前错误位置,从而在译码之前预先纠错的容错处理方法。由于容错后的数据流恢复了部分错误,误码率得到降低,因此译码结果明显改善。仿真结果显示,当信源载荷率为30%时,通过利用固定字段,容错译码可获得0.5dB左右的信噪比增益。

Error-Resilient Decoding in the System with Self-Synchronization Scrambling Code by Utilizing Constant Bytes

Shannon indicated that any redundancy can be utilized to battle noise at the receiver.Since the constant bytes in data streams can be considered as redundancy,this paper investigates the utilization of constant bytes to help decoding in the system with self-synchronization scrambling.An error-resilient scheme including several steps is proposed:first we extract information bits from the hard decisions of demodulator output and descramble them,then detect the const bytes and locate the errors in the descrambled data,and finally map the error positions back into the scrambled data and correct the corresponding errors before sending it into the channel decoder.Since this error-resilient process decreases the errors in data streams,the performance improvement after decoding is expected.The simulation results show that a gain of about 0.5 dB in signal-noise ratio can be obtained by utilizing the constant bytes at a payload rate of 30%.