GENERALIZED CONCATENATION OF CONVOLUTIONAL-CODES

Generalized concatenation of inner and outer convolutional codes is st udied. The essential problem is the partitioning of the inner code. A construction procedure to obtain a suitable equivalent description for a given code is derived, which gives the best possible distances in t he partitioned subcodes. The construction rule is illustrated with two examples. A small code is studied to emphasize the ideas of the const ruction and a large code, namely the satellite standard code, demonstr ates the considerable gains in decoding performance when using general ized concatenation. Furthermore, the possibilities for iterative decod ing are pointed out.