In this paper, a joint user association (UA) scheme with JP-CoMP using a hybrid self-organizing network (SON) is proposed for a practical clustered heterogeneous cellular network (cHCN) to maximize the network-wide proportional fairness among users. The cell range expansion and the enhanced intercell interference coordination have been considered as key items in the long-Term evolution-Advanced to offload macrocell users to small-cell base stations (sBSs). However, in a cHCN where sBSs are not distributed at random but are clustered instead, the coverage of inner sBSs in a small-cell cluster would be hardly expanded and an increased bias may result in much poor link quality as well as much higher load in outer sBSs. Thus, the load-balancing capability becomes much lower than expected in a cHCN. In order to cope with such a problem, a network architecture and protocol for the cHCN is suggested, and a feasible suboptimal iterative algorithm for determining the joint UA solution of the proposed hybrid SON is provided. It is shown that the proposed hybrid SON scheme with the proposed joint UA solution is very effective in handling the load balancing in a practical cHCN not only improving the performance of the inner sBS users by reducing the intercell interference, especially for intratier offloaded users, but also enabling more aggressive intertier offloading by effectively improving the link quality of cluster edge users without causing an unnecessary resource waste.
Bibliographical noteFunding Information:
Manuscript received September 19, 2016; revised March 29, 2017 and August 6, 2017; accepted August 22, 2017. Date of publication September 4, 2017; date of current version January 15, 2018. This work was supported by the Institute for Information and communications Technology Promotion grant funded by the Korea government (2014-0-00552, Next Generation WLAN System with High Efficient Performance and 2016-0-00208, High Accurate Positioning Enabled MIMO Transmission and Network Technologies for Next 5G-V2X (vehicle-to-everything) Services) and Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (NRF-2014R1A2A2A01007254). The review of this paper was coordinated by Prof. Y.-B. Lin. (Corresponding author: Kwang Soon Kim.) The authors are with the Department of Electrical and Electronic Engineering, Yonsei University, Seoul 03722, South Korea (e-mail: spacey2k@ dcl.yonsei.ac.kr; firstname.lastname@example.org).
All Science Journal Classification (ASJC) codes
- Automotive Engineering
- Aerospace Engineering
- Electrical and Electronic Engineering
- Applied Mathematics