Robust Resource Allocation for Two-Tier HetNets: An Interference-Efficiency Perspective

IEEE Transactions on Green Communications and Networking, vol. 5, pp. 1514–1528

Abstract

The heterogeneous network (HetNet) is a promising network for beyond 5G to improve network capacity and spectral efficiency by developing low-power small cells within macro networks. Therefore, appropriate resource allocation schemes should be designed to balance between data rates and the cross-tier interference among different cells. To improve system robustness and also reduce the harmful interference to macrocell users (MUs), in this paper, we maximize the total interference efficiency (IE) (i.e., the ratio of the sum data rates of femtocell users (FUs) to the total cross-tier interference from femtocell base stations (FBSs) to MUs) with imperfect channel state information in a two-tier orthogonal frequency division multiple access based HetNet by jointly optimizing the transmit power of the FBS and the subcarrier allocation factor. Meanwhile, the outage rate constraint of each FU, the outage interference constraint of each MU, the maximum transmit power constraint of the FBS, and the subcarrier assignment constraint are considered simultaneously. The considered problem belongs to a mixed-integer non-linear programming problem and thus is NP-hard. The original problem with uncertain parameters is transformed into a deterministic and convex one solved by using the quadratic transformation approach, the variable relaxation approach, and Lagrange dual theory. The feasible region analysis and robust sensitivity are provided. Simulation results demonstrate that the proposed scheme has a lower interference to the MU and higher IE by comparing it with the traditional schemes.

Authors 7

1. Yongjun Xu

   Chongqing University of Posts and Telecommunications · Shandong University · Xi’an University of Posts and Telecommunications

   Affiliation as printed

   School of Communication and Information Engineering, Chongqing Key Laboratory of Mobile Communications Technology, Chongqing University of Posts and Telecommunications, Chongqing, China

   Shaanxi Key Laboratory of Information Communication Network and Security, Xi’an University of Posts and Telecommunications, Xi’an, China

   Shandong Provincial Key Laboratory of Wireless Communication Technologies, Shandong University, Jinan, China

   Shaanxi Key Laboratory of Information Communication Network and Security, Xi'an University of Posts and Telecommunications, Xi'an, China

2. Guan Gui

   Nanjing University of Posts and Telecommunications

   Affiliation as printed

   College of Telecommunications and Information Engineering, Nanjing University of Posts and Telecommunications, Nanjing, China

3. Tomoaki Otsuki Ohtsuki

   Keio University

   Affiliation as printed

   Keio University, Yokohama, Japan

4. Haris Gacanin Aachen Faculty of Electrical Engineering and Information Technology

   RWTH Aachen University

   Affiliation as printed

   Faculty of Electrical Engineering and Information Technology, RWTH Aachen University, Aachen, Germany

5. Bamidele Adebisi

   Manchester Metropolitan University

   Affiliation as printed

   Faculty of Science and Engineering, Manchester Metropolitan University, Manchester, U.K

6. Hikmet Sari

   Nanjing University of Posts and Telecommunications

   Affiliation as printed

   College of Telecommunications and Information Engineering, Nanjing University of Posts and Telecommunications, Nanjing, China

7. Fumiyuki Adachi

   Tohoku University

   Affiliation as printed

   Research Organization of Electrical Communication, Tohoku University, Sendai, Japan