Performance Analysis of Pair-Wise Dynamic Multi-User Joint Transmission

In multi-cell cooperative networks, base station (BS) cooperation with BS clustering is indispensable for alleviating cooperation costs (e.g., data and channel estimation sharing via backhaul links). The performance of such BS cooperation is fundamentally limited by the unmanageable out-of-cluster interference. The out-of-cluster interference power is mainly a function of a set of the distances from the out-of-cluster BSs to users, the path-loss exponent, the cluster size, and the cooperative transmission strategies used in the out-of-cluster. Moreover, it is unclear how to analytically quantify both the out-of-cluster interference and the desired signal power. This makes the performance analysis of the cluster-based BS cooperation to be challenging. 

 

In this research, WNCG PhD student Jeonghun Park, WNCG alumnus Namyoon Lee, and WNCG Professor Robert Heath characterize the performance of multi-user joint transmission (MU-JT) with pair-wise dynamic base station (BS) clustering. Using tools from stochastic geometry, they derived a tight lower bound of the instantaneous signal-to-interference ratio (SIR) distribution in a closed-form in terms of relevant system parameters: the path-loss exponent and the topologies of users in the BS cooperative region. Using this bound, the performance of such BS cooperation is analyzed. Their key finding is that pair-wise dynamic BS cooperation through MU-JT provides a better rate coverage performance than that of a single-user joint transmission (SU-JT) over the entire range of the rate threshold when each user is close enough to the associated BS. 

 

This work will appear in the 2015 IEEE ICC conference. The preprint is available only for affiliates. This research was supported in part by Huawei Technologies.