Cooperative communications system with spatially random relays

Cooperative communications is a multiuser framework for wireless network environments. The collaboration among the users can exploit the inherent spatial diversity gains to thereby enhance the system performance significantly. Due to the mobility of users, especially in cellular systems, the exact locations of them are usually unknown a priori and hard/costly to discover. Therefore it is reasonable to model their locations as Bernoulli process. In this work, the uplink of a microcell in a decode-and-forward cooperative cellular system is investigated. The outage probability is derived based on a practical channel model including not only path loss but also shadowing and multipath fading effects. It is shown that considerable performance gains can be obtained.