Joint Optimization Framework for Operational Cost Minimization in Green Coverage-Constrained Wireless Networks

In this work, we investigate the joint optimization of base station (BS) location, its density, and transmit power allocation to minimize the overall network operational cost required to meet an underlying coverage constraint at each user equipment (UE), which is randomly deployed following the binomial point process (BPP). As this joint optimization problem is nonconvex and combinatorial in nature, we propose a non-trivial solution methodology that effectively decouples it into three individual optimization problems. Firstly, by using the distance distribution of the farthest UE from the BS, we present novel insights on optimal BS location in an optimal sectoring type for a given number of BSs. After that we provide a tight approximation for the optimal transmit power allocation to each BS. Lastly, using the latter two results, the optimal number of BSs that minimize the operational cost is obtained. Also, we have investigated both circular and square field deployments. Numerical results validate the analysis and provide practical insights on optimal BS deployment. We observe that the proposed joint optimization framework, that solves the coverage probability versus operational cost tradeoff, can yield a significant reduction of about 65% in the operational cost as compared to the benchmark fixed allocation scheme. Index Terms Base station location management; coverage probability; network operational cost; power allocation; optimization; green network deployment G. Prasad and A. Hossain are with the Department of Electronics and Communication Engineering, National Institute of Technology, Silchar, India (e-mail: {gpkeshri, ashraf}@ece.nits.ac.in). D. Mishra is with the Department of Electrical Engineering, Indian Institute of Technology Delhi, 110016 New Delhi, India (e-mail: [email protected]). A preliminary five-page conference version [1] of this work has been submitted to IEEE Int. Symp. Personal Indoor and Mobile Radio Commun. (PIMRC) 2017.