Hamming and Symbol-Pair Distances of Repeated-Root Constacyclic Codes of Prime Power Lengths Over $\mathbb F_{p^m}+u\mathbb F_{p^m}$
Hai Quang Dinh, Bac Trong Nguyen, Abhay Kumar Singh, Songsak Sriboonchitta · IEEE Communications Letters · 2018
The ring R = Fpm+ uFpmhas precisely pm(pm-1) units which are of the forms γ and α + uβ, where 0 ≠ α, β, γ ϵ Fpm. Using generator polynomial structures of constacyclic codes of length psover R, the Hamming and symbol pair distance distributions of all such codes are completely determined. As examples, we provide some good codes with better parameters than the known ones.