Investigation on Channel Estimation Techniques for MIMO- OFDM System for QAM/QPSK Modulation
Multiple Input Multiple Output (MIMO) systems has provide high transmission data rate without increasing transmitting power for wireless communication systems. The performance can be further improved by properly estimating the channel at the receiver side. In this paper, investigation on various channel estimation techniques for MIMO-OFDM has been done and a new approach based on Time-Domain Interpolation (TDI) has been presented. TDI is obtained by transforming output of estimator to time domain through Inverse Discrete Fourier Transform (IDFT), zero padding and going back to frequency domain through Discrete Fourier Transform (DFT).