Mobile Relaying: Coverage Extension and Throughput Enhancement

This paper presents a quantitative study of the benefits that mobile relays can provide to the wireless infrastructure namely, extension of base station coverage and enhancement of wireless connection throughput. The end user can choose to connect directly to a base station, or, as an alternative, to establish a two-hop link using a relay. Relay locations are modelled as realizations of a two-dimensional Poisson process with random motion, and as such their availability to forward messages received from a base station or from an end user is analyzed. Two important performance metrics are derived for out-of-coverage end users: the probability of establishing a route and the expected duration that a route or connection can be sustained. For an end user within the coverage area, the maximum and average throughput gains that can be achieved using mobile relays are derived. These results provide insight into the benefits mobile relays can offer in terms of improving connectivity or throughput.