Optimal Design of Energy-Efficient HetNets: Joint Precoding and Load Balancing
Paper in proceeding, 2015

This paper considers the downlink of a heterogeneous network, where multiple base stations (BSs) can serve the users by non-coherent multiflow beamforming. We assume imperfect channel state information at both BSs and users. The objective is to jointly optimize the precoding, load balancing, and BS operation mode (active or sleep) for improving the energy efficiency of the network. The considered problem is to minimize the weighted total power consumption (both circuit power and dynamic transmit power), while satisfying per-user quality of service constraints and per-BS transmit power constraints. This problem is non-convex, but we prove that for each combination of BS modes, the considered problem has a hidden convexity structure. Thus, the global optimal solution is obtained by an exhaustive search over all possible BS mode combinations. Furthermore, by iterative convex approximations of the non-convex power consumption functions, a heuristic algorithm is proposed to obtain a local optimal solution with low complexity. Simulation results illustrate that our proposed algorithms significantly reduce the total power consumption, compared to the scheme where all BSs are continuously active. This implies that putting a BS into sleep mode by proper load balancing is an important solution for energy savings in heterogeneous networks.


Jingya Li

Chalmers, Signals and Systems, Communication, Antennas and Optical Networks

E. Björnson

Linköping University

Tommy Svensson

Chalmers, Signals and Systems, Communication, Antennas and Optical Networks

Thomas Eriksson

Chalmers, Signals and Systems, Communication, Antennas and Optical Networks

Mérouane DEBBAH

SUPELEC Campus de Gif

IEEE International Conference on Communications

15503607 (ISSN)

4664-4669 7249059
978-1-4673-6432-4 (ISBN)

Areas of Advance

Information and Communication Technology

Subject Categories


Communication Systems

Signal Processing


C3SE (Chalmers Centre for Computational Science and Engineering)





More information

Latest update