Multi-user chirp modulation signals (M-CM) for efficient multiple-access communication systems

We present a novel technique for a multi-user communication system utilizing binary chirp modulated (CM) signals. This suggested technique is motivated by the inherent interference rejection capability of such spread-spectrum type system, specially in circumstances where immunity against Doppler shift and fading due to multipath propagation are important. The chirp signals used are selected such that they all have the same power as well as the same bandwidth. Closed form expressions, as well as approximate analytical expressions, for the cross-coherence functions between the different forms of considered chirp signals are derived. The performance of a suggested coherent receiver structure is investigated and the corresponding error rates are presented. The results show that the proposed multi-user chirp signaling technique is efficient and promising as a multiple-access technique.