一种基于分类搜索的Gold误码修正算法

摘要

In the countermeasuring of blind processing spread spectrum system with a very low signal-to-noise ratio(SNR),the estimated spreading codes always contain error codes,which can affect the quality of despreading and demodulating the spreading codes.A strict classification scheme is presented according to cross-correlation function and the basic characteristics of the preferred pair of m sequence.And an error correction algorithm based on classification search is proposed,which can quickly search and locate the corresponding code by comparing the three-valued distribution of the cross-correlation function between the test code and the sample Gold codes of each category.Simulations illustrate that the proposed algorithm can completely correct the error codes when the bit error rate(BER) is lower than 11% and also effectively reduce the SNR threshold for the blind processing of spread spectrum signals.%扩频系统侦察对抗时,在低信噪比下估计得到的扩频码存在严重误码,会影响信号解扩解调质量.通过Gold码与其对应m序列优选对的基本特性结合互相关函数特征,提出了一种严格的Gold码分类,并得出一种基于分类搜索的误码修正算法,通过比较待测Gold码与各类样本Gold码互相关函数的三值分布特性,可以快速搜索准确定位到正确的Gold码,实现误码完全修正.当Gold码的误码率不高于11%时,算法可实现对误码的完全修正,能有效降低扩频信号盲处理的信噪比门限.