Cooperative Base Station Coloring for Pair-Wise Cluster Multiplexing

Coordination among base stations (BS) is a powerful approach for mitigating inter-cell interference and maximizing the sum spectral efficiency in cellular systems. In practice, however, coordination with a large number of BS may not be feasible due to excessive overheads associated with BS coordination, e.g., complexity, channel estimation and channel feedback. One practical solution for implementing multi-cell coordination is, therefore, to form a BS cluster so that a limited number of BS are coordinated to control intra-cluster interference with a reasonable amount of overhead. Unfortunately, when clustering-based BS coordination is applied in a static way, the performance of a user (especially cell edge users) is mainly limited by the unmanageable out-of-cluster interference. To address this problem, WNCG PhD student Jeonghun Park, WNCG alumnus Namyoon Lee, and WNCG Professor Robert Heath proposed an efficient BS coordination strategy that protects edge users from dominant out-of-cluster interference in irregular cellular network models. Specifically, each BS cluster is formed by using the 2nd-order Voronoi region of a set of deployed BS' locations. The formed BS clusters are assigned to multiple cluster patterns by exploiting the corresponding edge-coloring. The key advantage of the proposed method is that every user is guaranteed to be served by the two closest BS irrespective of the BS deployment scenario. Their results indicate that the proposed coordination strategy provides considerable performance gains in both the rate coverage probability and the ergodic spectral efficiency for cell edge users when compared to conventional cooperative strategies. This work is in preparation to be submitted to IEEE Transactions on Wireless Communication. The preprint is available only for affiliates.

This research was supported in part by Huawei Technologies.