A new and conceptually simple semidefinite relaxation approach is proposed for MIMO detection in communication systems employing high-order QAM constellations. The new approach affords improved detection performance compared to existing solutions of comparable worst-case complexity order, which is nearly cubic in the dimension of the transmitted symbol vector and independent of the constellation order for uniform QAM, or affine in the constellation order for nonuniform QAM.
Bibliographical noteFunding Information:
Manuscript received November 10, 2005; revised February 27, 2006. The work of N. D. Sidiropoulos was supported in part by the U.S. ARO under ERO Contract N62558-03-C-0012, in part by the European Union under FP6 U-BROAD STREP # 506790, and in part by the GSRT. The work of Z.-Q. Luo was supported in part by the National Science Foundation under Grant DMS-0312416. The associate editor coordinating the review of this manuscript and approving it for publication was Dr. Philip Schniter.
- High-order QAM
- Integer least squares
- Lattice search
- Multi-user detection
- Multiple-input multiple-output (MIMO) detection
- Semidefinite programming
- Semidefinite relaxation (SDR)