Achieving wireline random access throughput in wireless networking via user cooperation

Well appreciated at the physical layer, user cooperation is introduced here as a diversity enabler for wireless random access (RA) at the medium access control sub-layer. This is accomplished through a two-phase protocol in which active users start with a low power transmission attempting to reach nearby users, and follow up with a high power transmission in cooperation with the users recruited in the first phase. We show that such a cooperative protocol yields a significant increase in throughput. Specifically, we prove that for networks with a large number of users, the throughput of a cooperative wireless RA network operating over Rayleigh fading links approaches the throughput of a RA network operating over additive white Gaussian noise (AWGN) links. As a result, user cooperation migrates diversity benefits to the wireless RA regime, thus bridging the gap to wireline RA networks, without incurring a bandwidth or energy penalty.