Cooperative Base Station Coloring for Pair-wise Multi-Cell Coordination
Jeonghun Park, Namyoon Lee, and R. W. Heath, Jr.
submitted to IEEE Transactions on Communications.
A semi-static base station (BS) coordination strategy exploits predefined multiple BS cluster patterns for cooperative transmissions to improve the cell-edge user throughput. This paper proposes an efficient BS cluster pattern for pair-wise semi-static BS coordination, where edge users are guaranteed to be protected from dominant out-of-cluster interference in an irregular cellular network. The key idea is that each BS cluster is formed by using the 2nd-order Voronoi region of BSs’ locations and formed BS clusters are assigned to multiple cluster patterns by using the edge-coloring. The main advantage of the proposed BS cluster pattern is that every user is guaranteed to be served by the two closest BSs irrespective of a BS deployment scenario. With the proposed coordination strategy, analytical expressions for the rate distribution and the ergodic spectral efficiency are derived as a function of relevant system parameters in a non-random network model with irregular BS locations. A lower bound on the ergodic spectral efficiency is characterized for a random network where locations of BSs and users are modeled by using a homogeneous Poisson point process. Through simulations, the analytical expressions are verified, and the performance is compared with that of conventional methods. Our major finding is that the proposed BS cluster pattern provides considerable performance gains in both the rate coverage probability and the ergodic spectral efficiency for cell-edge users compared to conventional strategies.