Some results on convolutional codes over rings

In English Convolutional codes over rings were motivated from phase-modulated signals. Some structural properties of generator matrices of convolutional codes over rings have been studied. A condition for a convolutional code over a ring to be systematic is given and shown to be equivalent to the condition given by Massey and Mittelholzer (1989). Furthermore, the conditions of generator matrices over Z(pe) being catastrophic, basic, and minimal are considered, and the predictable degree property of polynomial generator matrices is considered.