Publica
Hier finden Sie wissenschaftliche Publikationen aus den FraunhoferInstituten. Energy Efficiency Optimization in MIMO Interference Channels: A Successive Pseudoconvex Approximation Approach
 IEEE transactions on signal processing 67 (2019), Nr.15, S.41074121 ISSN: 00963518 ISSN: 00189278 ISSN: 00961620 ISSN: 1053587X 

 Englisch 
 Zeitschriftenaufsatz 
 Fraunhofer ITWM () 
Abstract
In this paper, we consider the (global and sum) energy efficiency optimization problem in downlink multiinput multioutput multicell systems, where all users suffer from multiuser interference. This is a challenging problem due to several reasons: First, it is a nonconvex fractional programming problem; second, the transmission rate functions are characterized by (complexvalued) transmit covariance matrices; and third the processingrelated power consumption may depend on the transmission rate. We tackle this problem by the successive pseudoconvex approximation approach, and we argue that pseudoconvex optimization plays a fundamental role in designing novel iterative algorithms, not only because every locally optimal point of a pseudoconvex optimization problem is also globally optimal but also because a descent direction is easily obtained from every optimal point of a pseudoconvex optimization problem. The proposed algorithms have the following advantages: First, fast convergence as the structure of the original optimization problem is preserved as much as possible in the approximate problem solved in each iteration; second, easy implementation as each approximate problem is suitable for parallel computation and its solution has a closedform expression; and third, guaranteed convergence to a stationary point or a KarushKuhnTucker point. The advantages of the proposed algorithm are also illustrated numerically.