基于匹配搜索的伪随机序列生成多项式估计

摘要

The generator polynomial estimation of a pseudo-random sequence in truncated codes or error codes is studied in the paper. An optimum estimation algorithm for the generator polynomial via a match-searching is proposed by constructing verification equations based on the linear principle of the pseudo-random sequence. The important characteristic of reducible polynomial in GF(2) is used by reducing the computational amount in algorithm optimization. Finally, the estimation performance of the algorithm at different thresholds and bit errors is simulated,and the performance of the algorithm for the truncated codes or error codes is compared with that of the typical algorithm by taking m-se-quences as an example. Simulation results indicate that the algorithm has good adaptability for the error codes and truncated codes and it completes a estimation for the m-sequences with rank of 15 andcan adapte to an error rate more than 20%. The algorithm can preferably meets engineering application requirements.%对截短和误码条件下伪随机序列生成多项式估计算法的误码适应性进行了研究.根据伪随机序列的线性约束原理,通过构造关于生成多项式系数的校验方程组,提出了基于匹配搜索方法的生成多项式估计算法,并在搜索过程中利用生成多项式在二元域的基本特性缩小搜索范围来优化算法,减少计算量.最后,对算法在不同门限值和误码率时的估计性能进行了仿真,且以m序列为例,对本算法与典型算法在截短序列和误码适应性方面进行性能对比.仿真结果表明,该算法能较好完成对15阶m序列生成多项式的估计,可以适应20％以上的误码率,与现有算法相比,本算法具有更好的误码和截短序列适应性,能较好地满足工程实践中扩频序列分析的需要.