Semidefinite Relaxation of the 16-QAM Maximum Likelihood Detector
نویسندگان
چکیده
We develop a computationally efficient approximation of the maximum likelihood (ML) detector for 16 Quadrature Amplitude Modulation (16QAM) in multiple input multiple output (MIMO) systems. The detector is based on a semi definite relaxation (SDR) of the ML problem. The resulting optimization is a semi definite program (SDP) which can be solved in polynomial time with respect to the number of inputs in the system. Simulation results show that the SDR outperforms the conventional decorrelator detector by about 2.5dB.
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