[SEEM Seminar Announcement] Date: September, 16, 2013 (Monday) Time: 4:30 PM - 5:30 PM

                Department of Systems Engineering and Engineering Management
                             The Chinese University of Hong Kong
Title of the talk: Robust SINR-Constrained MISO Downlink Beamforming: When is Semidefinite Programming Relaxation Tight?
Speaker Information: Prof. Enbin Song from Sichuan University, PRC
Date: Monday, September 16, 2013
Time: 4:30 PM to 5:30 PM
Venue:     Room 513,
                William M.W. Mong Engineering Building,
                (Engineering Building Complex Phase 2)
                The Chinese University of Hong Kong.
We consider the multiuser beamforming problem for a multi-input single-output downlink channel that takes into account the errors in the channel state information at the transmitter side (CSIT). By modeling the CSIT errors as elliptically bounded uncertainty regions, this problem can be formulated as minimizing the transmission power subject to the worst-case signal-to-interference-plus-noise ratio constraints. Several methods have been proposed to solve this nonconvex optimization problem, but none can guarantee a global optimal solution. In this article, we consider a semidefinite relaxation (SDR) for this multiuser beamforming problem, and prove that the SDR method actually solves the robust beamforming problem to global optimality as long as the channel uncertainty bound is sufficiently small or when the transmitter is equipped with at most two antennas. Numerical examples show that the proposed SDR approach significantly outperforms the existing methods in terms of the average required power consumption at the transmitter. 


Presenter's Biography: 
Enbin Song received the degree of the bachelor of science from Shandong Normal University in 2002. In 2007, he received the Ph.D. degree from Sichuan University, China. He was a visiting scholar at School of Electronic & Information Engineering, Xi’an Jiao Tong University from September 2007 to January 2008. From February 2008 to March 2010, he was a postdoctoral at Department of Computer Science, Sichuan University and from April 2010 to May 2011, he was a postdoctoral at Department of Electrical and Computer Engineering, University of Minnesota. From May 2011, he is an associate professor in the Department of Mathematics, Sichuan University. His main research interests are in information processing and nonlinear optimization and its application, including multi-sensor estimation and decision fusion theory, the theory of multi-user wireless communications, particularly, with an emphasis on the application of optimization techniques to signal processing.


Work done in collaboration with:

Qingjiang Shi, Maziar Sanjabi, Ruoyu Sun and Zhi-Quan Luo


Everyone is invited to attend the talk.



Host: Prof. Shiqian Ma

Telephone Number: (852) 3943-8240
For enquiries, please get in touch with:
Prof. Shiqian Ma or Prof. Lingfei Li
Department of Systems Engineering and Engineering Management
The Chinese University of Hong Kong
Prof. Lingfei Li can be contacted at:
Telephone Number: (852) 3943-8329
SEEM-5201 Website:
Monday, September 16, 2013 - 08:30 to 09:30