由Ｉｍａｉ与Ｈｉｒａｋａｗａ提出的多级编码方法，可用来构造具有任意大最小平方欧氏距离的分组调制（ＢＣＭ）码一个ＢＣＭ码的性能主要取决于构成它的各个成分码，恰当地选择成分码是构造一个好的ＢＣＭ码的关键，文章给出了一种新方法，通过选用不同长度的成分码来构造ＢＣＭ码，仿真结果表明用此方法构造出的ＢＣＭ码较传统的ＢＣＭ码在性能与复杂度上有明显的改善 The multi-level coding method proposed by Imai and Hirakawa, which can be used to construct a BCM code with any large, least square Euclidean distance. The performance of a BCM code depends primarily on the individual component codes that make up it. The proper choice of component codes is The key to construct a good BCM code is to give a new method to construct the BCM code by using component codes of different lengths. The simulation results show that the BCM codes constructed by this method are more complex than the traditional BCM codes in performance and complexity Degree significantly improved