A Study on Dual-Polarized MIMO-ICI Canceller With Complexity Reduction Under Mobile Reception of OFDM Signals

In the next Japanese digital terrestrial television broadcasting systems, the scheme that combines orthogonal frequency division multiplexing (OFDM) and dual-polarized multi-input multi-output (MIMO) is proposed. One of the major problems to be considered is inter-carrier interference (ICI) that is generated by Doppler-spread under mobile reception of MIMO-OFDM systems. In this case, reception characteristics are deteriorated significantly. The ICI canceller for MIMO-OFDM can demodulate transmitted symbols. To realize the MIMO-ICI canceller based on zero-forcing (ZF), it is necessary to reduce the complex calculations such as matrix operations. Therefore, complexity reduction of the MIMO-ICI canceller is proposed. The proposed MIMO-ICI canceller with complexity reduction based on ZF can improve the influence of ICI with low complexity. However, reception characteristics are deteriorated as compared to the MIMO-ICI canceller based on ZF. Thus, improving scheme of MIMO-ICI canceller with complexity reduction based on ZF is proposed. In the proposed scheme, the iterative detection is adopted. In addition, MIMO-ICI cancellers based on minimum mean square error (MMSE) are proposed. As the results of computer simulations, the MIMO-ICI cancellers using iterative detection based on ZF and MMSE can improve the reception characteristics with low complexity.