Performance Analysis of Client Relay Cloud in Wireless Cellular Networks

Abstract

Cooperative communication is a promising concept to mitigate the effect of fading in a wireless channel and is expected to improve performance of next-generation cellular networks in terms of client throughput and energy efficiency. With recent proliferation of smart phones and machine-to-machine communication, so-called ’client relay’ cooperative techniques are becoming more important. As such, a mobile client with poor channel quality may take advantage of other neighboring clients, who would relay data on its behalf. In the extreme, the aggregate set of available client relays may form a relay cloud, and members of the cloud may opportunistically cooperate with the data originator to improve its uplink channel quality. The key idea behind the relay cloud is to provide flexible and distributed control over cooperative communication by the wireless clients themselves. By contrast to centralized control, this will minimize extra protocol signaling involved and ensure simpler implementation. In this work, we build an originator-centric model and study the performance of a relay cloud with respect to the main performance metrics: throughput, packet delay, and energy efficiency. We obtain closed-form analytical expressions for the sought metrics and verify our results via extensive simulations.