Information retrieval and processing in sensor networks: deterministic scheduling vs. random access

The effect of medium access control (MAC) for information retrieval on signal field reconstruction in large-scale sensor networks with finite density is analyzed. Two MAC schemes are compared: the deterministic scheduling and random access. For fixed sensor density, we show that there is a critical threshold of e^-λ(1+o(1)), where λ is the throughput of the random access protocol, on the sensor outage probability P_out beyond which the reconstruction performance of deterministic central scheduling is inferior to that of distributed random access.