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**Harvard**

Li, J., Bjornson, E., Svensson, T., Eriksson, T. och Debbah, M. (2015) *Joint Precoding and Load Balancing Optimization for Energy-Efficient Heterogeneous Networks*.

** BibTeX **

@article{

Li2015,

author={Li, Jingya and Bjornson, E. and Svensson, Tommy and Eriksson, Thomas and Debbah, M.},

title={Joint Precoding and Load Balancing Optimization for Energy-Efficient Heterogeneous Networks},

journal={IEEE Transactions on Wireless Communications},

issn={1536-1276},

volume={14},

issue={10},

pages={5810-5822},

abstract={This paper considers a downlink heterogeneous network, where different types of multiantenna base stations (BSs) communicate with a number of single-antenna users. Multiple BSs can serve the users by spatial multiflow transmission techniques. Assuming imperfect channel state information at both BSs and users, the precoding, load balancing, and BS operation mode are jointly optimized for improving the network energy efficiency. We minimize the weighted total power consumption while satisfying quality-of-service constraints at the users. This problem is nonconvex, but we prove that for each BS mode combination, the considered problem has a hidden convexity structure. Thus, the optimal solution is obtained by an exhaustive search over all possible BS mode combinations. Furthermore, by iterative convex approximations of the nonconvex objective function, a heuristic algorithm is proposed to obtain a suboptimal solution of low complexity. We show that although multicell joint transmission is allowed, in most cases, it is optimal for each user to be served by a single BS. The optimal BS association condition is parameterized, which reveals how it is impacted by different system parameters. Simulation results indicate that putting a BS into sleep mode by proper load balancing is an important solution for energy savings.},

year={2015},

keywords={Energy efficiency, heterogeneous networks, load balancing, precoding design },

}

** RefWorks **

RT Journal Article

SR Electronic

ID 227660

A1 Li, Jingya

A1 Bjornson, E.

A1 Svensson, Tommy

A1 Eriksson, Thomas

A1 Debbah, M.

T1 Joint Precoding and Load Balancing Optimization for Energy-Efficient Heterogeneous Networks

YR 2015

JF IEEE Transactions on Wireless Communications

SN 1536-1276

VO 14

IS 10

SP 5810

OP 5822

AB This paper considers a downlink heterogeneous network, where different types of multiantenna base stations (BSs) communicate with a number of single-antenna users. Multiple BSs can serve the users by spatial multiflow transmission techniques. Assuming imperfect channel state information at both BSs and users, the precoding, load balancing, and BS operation mode are jointly optimized for improving the network energy efficiency. We minimize the weighted total power consumption while satisfying quality-of-service constraints at the users. This problem is nonconvex, but we prove that for each BS mode combination, the considered problem has a hidden convexity structure. Thus, the optimal solution is obtained by an exhaustive search over all possible BS mode combinations. Furthermore, by iterative convex approximations of the nonconvex objective function, a heuristic algorithm is proposed to obtain a suboptimal solution of low complexity. We show that although multicell joint transmission is allowed, in most cases, it is optimal for each user to be served by a single BS. The optimal BS association condition is parameterized, which reveals how it is impacted by different system parameters. Simulation results indicate that putting a BS into sleep mode by proper load balancing is an important solution for energy savings.

LA eng

DO 10.1109/twc.2015.2443044

LK http://dx.doi.org/10.1109/twc.2015.2443044

OL 30