Robust resource allocation for two-tier HetNets: An interference-efficiency perspective

Yongjun Xu, Guan Gui, Tomoaki Ohtsuki, Haris Gacanin, Bamidele Adebisi, Hikmet Sari, Fumiyuki Adachi

Research output: Contribution to journalArticlepeer-review

18 Citations (Scopus)


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.

Original languageEnglish
Article number9459965
Pages (from-to)1514-1528
Number of pages15
JournalIEEE Transactions on Green Communications and Networking
Issue number3
Publication statusPublished - 2021 Sept


  • Heterogeneous networks
  • interference efficiency
  • robust resource allocation

ASJC Scopus subject areas

  • Renewable Energy, Sustainability and the Environment
  • Computer Networks and Communications


Dive into the research topics of 'Robust resource allocation for two-tier HetNets: An interference-efficiency perspective'. Together they form a unique fingerprint.

Cite this