Joint Channel Estimation and Symbol Detection in Overloaded MIMO Using ADMM.

This paper proposes a Joint Channel Estimation and Symbol Detection (JED) scheme for overloaded multiple-input multiple-output (MIMO) wireless communication systems, with the number of receive antennas being less than or equal to the number of transmit antennas. Our proposed method for JED using Alternating Direction Method of Multipliers (JED-ADMM) markedly improves the symbol detection performance by yielding 12-16 dB gain in signal-to-noise ratio (SNR) for a bit error rate (BER) of 10(-3) over state-of-the-art JED using Alternating Minimization (JED-AM). This gain in BER for the proposed JED-ADMM is also accompanied by a significant reduction in computational complexity (1/4 times) as compared to JED-AM.