环R=Z4+uZ4+u2Z4既不是有限链环也不是主理想环,其中U3=0。文章研究了环Z4+uZ4+u2Z4上任意长度的循环码,确定了R上任意长度n的循环码的结构,定义了R到Z43的一个Gray映射,证明了R上长为n的循环码的Gray像是Z4上长为3n、指数为3的准循环码。
The ring R=Z4+uZ4+u2Z4 is neither a finite ring nor a principle ideal ring,, where u3 =0. In this paper, cyclic codes over R of an arbitrary length are studied. The structure of cyclic codes over R of length n is determined. A Gray map from R to Z43 is defined. It is proved that the Gray map of a cyclic code over R of length n is a quasi-cyclic code of length 3n and index 3 over Z4.