Linear and Nonlinear Time Domain Block Equalizers on MIMO Frequency Selective Channels

Cong Li, Yasunori Iwanami

Department of Computer Science and Engineering, Graduate School of Engineering, Nagoya Institute of Technology, Nagoya, Japan.

DOI: 10.4236/ijcns.2013.63014                

Abstract

Single-Carrier (SC) transmission with the same bandwidth as Multi-Carrier (MC) transmission (such as OFDM) may have far shorter symbol duration and is considered to be more robust against time selective fading. In this paper, we proposed the novel equalization and signal separation schemes in time domain for short block length transmission, i.e., Block Linear Equalization (BLE) and Block Nonlinear Equalization (BNLE) on MIMO frequency selective fading channels. The proposed BLE uses the MMSE based inverse matrix in time domain and the BNLE utilizes the QRD-M (QR Decomposition with M algorithm) with appropriate receiver complexity. We compared the computational complexity among the conventional SC-FDE (Frequency Domain Equalization) scheme and the proposed equalizers. We also used the Low-Density Parity Check (LDPC) decoder concatenated to the proposed BLE and BNLE.

Keywords

MIMO Frequency Selective Fading Channel; ISI; IAI; Time Domain Block Equalizer; BLE; BNLE

Conflicts of Interest

The authors declare no conflicts of interest.

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