Self-dual Abelian Codes over Z_4
Shengyuan Zhang · Journal of Fujian Normal University · 2005
Non-trivial,self-dual abelian codes of length n where n is odd over Z_4 exist if and only if n is either divisible by a prime r≡-1(mod 8),or a prime r≡1(mod 8) where ord_r (2)is odd,or a prime p and a prime q where ord_p(2)=2~li,ord_q(2)=2~lj,l≥ 1,i is odd,j is even.