Speaker: Assoc. Prof. Melda Yüksel, TOBB-ETÜ

Topic: "Precoder Design for Downlink Multiuser MIMO Systems"

Location: Middle East Technical University, Ankara, Turkey

Abstract: In this work, a downlink wireless communication channel is considered. The base station (BS) has common data for all users, unicast data for a set of intended users, and transmits the superposition of these messages. This setting neither falls into the non-orthogonal multiple access (NOMA) nor into the multi-group multicasting literatures. In NOMA systems, the BS has unicast data for all users, and multiple users share the same resources. In multi-group multicasting, there are non-overlapping groups, each demanding a different multicast message. This paper studies precoder design to achieve maximum weighted sum rate (WSR). It is first shown that the precoders designed for WSR maximization and weighted minimum mean square error (WMMSE) minimization are equivalent. Secondly, an iterative, low complexity algorithm (named as WMMSE), based on WMMSE transmit precoders and receivers, is proposed. Another low-complexity precoder, the phase aligned zero forcing (PAZF) precoder is also introduced. The results show that both algorithms converge fast. The WMMSE algorithm outperforms both PAZF and the zero-forcing (ZF) precoder for all signal-to-noise ratio (SNR) ranges. It offers better interference management and high coherent combining gains for common data, while PAZF finds the optimal phase rotation on the ZF precoder, and increases coherent combining gains.

Bio: Melda Yuksel received the B.S. degree in electrical and electronics engineering from Middle East Technical University, Ankara, Turkey, in 2001, and the Ph.D. degree in electrical engineering from Polytechnic Institute of New York University, Brooklyn, NY, in August 2007. She joined TOBB University of Economics and Technology, Ankara, Turkey, in Fall 2007, where she is currently an associate professor. Her research interests are in information theory, communication theory and wireless communications. Dr. Yuksel is the recipient of the best paper award at the Communication Theory Symposium of the 2007 IEEE International Conference on Communications and the Turkish National Science Foundation CAREER Award. Dr. Yuksel was the treasurer of 2013 IEEE International Symposium of Information Theory. She is currently serving as an editorial board member of PHYCOM, Physical Communication.

  Date and Time




  • Ankara, Ankara
  • Turkey



Assoc. Prof. Melda Yuksel


Precoder Design for Downlink Multiuser MIMO Systems