Performance analysis of Coarse Quantization for Multiuser MIMO OFDM System

Abstract

Orthogonal Frequency Division Multiplexing (OFDM) is a multi-carrier modulation technique with high spectral efficiency, low multi-path distortion, and resistance to RF interference.A Multiple-Input Multiple-Output (MIMO) structure coupled with OFDM provides a reliable communication across frequencyselective channels. The fifth generation of wireless communication systems is projected to include Multiuser (MU) MIMO as a significant technology. In this paper, a novel approach for channel estimation and data detection based on coarse quantization for MU-MIMO OFDM system is discussed. Manystudies have been conducted to investigate MIMO structures equipped with low-resolution Analog-to-DigitalConverters (ADCs).On quantized MIMO systems, the effect of a high interference in the adjacent band has not yet been assessed.The interfering band can be reduced by increasing the number of antennas or raising the sampling rate.We explored the related performance trade-offs and presented new quantized method, called asCoarse Quantization,applied for Maximum-a-Posteriori (MAP) channel estimation and Minimum MeanSquare Error (MMSE) data detection methods. Our research has shown that using coarse quantization in Multiuser MIMO-OFDM system results in essentially no performance loss when compared to the situation of infinite precision, and this occurs despite the fact that there is no extra cost in terms of the complexity of the baseband processing.