Joint optimization of coverage and capacity in heterogeneous cellular networks

This paper presents a framework for coverage and capacity optimization (CCO) in Heterogeneous Cellular Networks (HCNs). Unlike conventional approaches, we propose a concept of effective capacity (EC) as the optimization objective of CCO, which involves the index of coverage in the form of truncation function. The optimization objective is a NP problem due to that the adjusting parameters are mixed with discrete and continuous, i.e., antenna electronic down-tilt is discrete, while the transmission power and bandwidth are continuous. In this paper, we improve bacterial foraging (BF) algorithm based on taking the HCNs performance analysis of coverage and capacity with percentile level to find an effective increasing direction. According to simulation, the results show that the optimization objective is feasible and the adjustment of percentile level achieves flexible solutions for CCO.