Analysis of throughput gains from relays in cellular networks

Multihop wireless networking has traditionally been viewed in the context of ad-hoc and peer-to-peer networks. We consider the application of multihop networking in wide area cellular systems and evaluate potential capacity enhancements. A cellular system with relays that store and forward information from the base station to the terminals on the downlink is considered. With geographical routing for uniform placement of relays within a cell, upper bounds to throughput gains are derived for a transmission scheme that guarantees equal long term throughput to all users. Our results show that, for a large number of hops, the gain is limited by the rate on the links between the base and the closest set of relays