On the Low Rank Solutions for Linear Matrix Inequalities
Wenbao Ai,
Yongwei Huang,
Shuzhong Zhang
School of Science, Beijing University of Posts and Telecommunications, Beijing 100876, China
Department of Systems Engineering and Engineering Management, The Chinese University of Hong Kong, Hong Kong
Department of Systems Engineering and Engineering Management, The Chinese University of Hong Kong, Hong Kong
wenbaoai{at}gmail.com
ywhuang{at}se.cuhk.edu.hk
zhang{at}se.cuhk.edu.hk, http://www.se.cuhk.edu.hk/
zhang/
In this paper we present a polynomial-time procedure to find a low-rank solution for a system of linear matrix inequalities (LMI). The existence of such a low-rank solution was shown in the work of Au-Yeung and Poon and the work of Barvinok. In the approach of Au-Yeung and Poon an earlier unpublished manuscript of Bohnenblust played an essential role. Both proofs in the work of Au-Yeung and Poon and that of Barvinok are nonconstructive in nature. The aim of this paper is to provide a polynomial-time constructive procedure to find such a low-rank solution approximatively. Extensions of our new results and their relations to some of the known results in the literature are discussed.
Key Words: rank reduction; linear matrix inequality; joint numerical range
History: Received: October 1, 2006;
revision received: March 28, 2008;
Copyright © 2008 by INFORMS.