Channel estimation methods for MIMO-OFDM system: time domain versus frequency domain

This paper presents a simplified channel estimation technique for orthogonal frequency division multiplexing (OFDM) systems with multiple input, multiple output (MIMO) antenna structure. The estimation technique is presented both in the frequency and time domains. Quadrature phase shift keying (QPSK) modulation technique is used to modulate the transmitted data. To ensure low computational complexity, time domain estimated channel information is considered to evaluate the performance of the OFDM system in terms of symbol error rate (SER). For both channel estimation and performance evaluation, simulation results are presented for two-transmit and one-receive antenna configuration in the two-ray Rayleigh fading channel environment. The simulation results validate the analysis and justify the approximations made therein.