Non-cooperative block-faded orthogonal multiple access with source correlation: performance limits and practical schemes

In this paper, we study the performance of non-cooperative wireless multiple access systems with noisy separated channels, where correlated sources communicate to an access point (AP) in the presence of block-faded links. This is meaningful for pervasive wireless scenarios, e.g., wireless sensor networks, where information may be exchanged between a multitude of nodes. Our goal is to explore the potential benefits which can be obtained when source correlation is exploited at the AP, comparing the performance with that obtained by using distributed source coding (DSC) at the nodes. We consider both the average bit error probability and the outage probability as performance indicators, and we derive a theoretical approach to evaluate their limits. Our results show that the improvement brought by the exploitation of the correlation at the AP is more evident when the correlation becomes sufficiently high. Moreover, some simulation results are presented for two classes of channels codes: serially concatenated convolutional codes (SCCCs) and low-density parity-check (LDPC) codes. Our results show that SCCCs can exploit better the correlation in scenarios with high values of the correlation coefficient (e.g., 0.999).