RANDOM CODING BOUNDS FOR NONCOHERENT mFSK MULTIPLE-ACCESS CHANNELS

We investigate a time-varying trellis coded multiple-access scheme using noncoherent mFSK signals. Techniques similar to this were originally proposed by Cohen, Heller, and Viterbi[1] and more recently in a mFSK form by Viterbi.[2] In these multiple-access systems van der Muelen[3] Ahlswede[4] Liao[5], Gaarder and Wolf [6], Kasami and Lin[7], Weldon[8] and Wolf[9] have shown that the decoded symbols of one user can be used to reduce the “multiple-access noise” to other users and thus allow for a larger achievable rate region than one would expect with conventional time division multiple-access techniques. In some cases, specific codes were investigated. Peterson and Costello[10] and Chevillat[11] have extended these earlier works to convolutional and trellis codes. In this case the decoder is designed as a “super” Viterbi decoder that regards all transmitter trellis codes combined to form a single “super” trellis encoder.