k-错线性复杂度是度量密钥流序列的密码强度的一个重要指标.为了更好地刻画和研究序列的随机性,研究了周期为2^n的二元序列s_的k-错线性复杂度(Lct(s_))的分布情况,讨论了满足LCk(s_)-LC(s_+e_)条件下的k-错误序列e的分布情况.基于Games-Chan算法,通过将k-错线性复杂度的计算转化为求Hamming重量最小的错误序列的方法,给出了线性复杂度小于2^n的2^n周期二元序列的部分4-错误序列的计数公式.
The k-error linear complexity of a sequence has been used as one of the important measure of keystream strength. In order to better depict and study randomicity of sequences, the k-error sequences (e_) distribution that corresponds with LCk (s_)= LC (s_+ e_) is discussed by studying the distribution of k- error linear complexity of binary sequences (s) with period 2^n. Based on Games-Chan algorithm,it is proposed that the computation of k-error linear complexity should be converted to finding error sequences with minimal Hamming weight. For k =4, some the counting functions on the k-error sequences of 2^n-pe- riodic binary sequences with linear comolexitv less than 2^n are derived.