ADMOT: Compressive sensing techniques for channel monitoring in multiple access networks

This paper studies the overhead for channel gain monitoring in wireless networks with time division multiple access. We first investigate the scenario in which a receiver needs to track the channel gains with respect to multiple transmitters. Suppose that there are n transmitters, and no more than k channels suffer significant variations since the last round. We prove that "Θ(k log(n/k)) time slots" is the minimum overhead needed to catch up with the k varied channels. We propose a novel channel-gain monitoring scheme named ADMOT. ADMOT leverages recent advances in compressive sensing in signal processing and interference processing in wireless communication, to enable the receiver to estimate all n channels in a reliable and computationally efficient manner within O(k log(n/k)) time slots. To our best knowledge, all previous channel-tracking schemes require Θ(n) time slots regardless of k.