Performance of least square based channel estimation for high order modulation QAM-OFDM-MIMO in the presence of multipath fading channel: article / Izham Khairulfathi Bahro

As the communication system evolving and enhancing, the need for high speed and reliable communication system is crucial. With the combination of multiple-input multiple-output (MIMO) communication system along orthogonal frequency division multiplexing (OFDM), a reliable high rate communication system can be achieved. The MIMO OFDM system with 2X2, 3x3, and 4x4 antenna configurations will use 256, 512 and 1024 QAM modulation level in the presence of multipath Rayleigh and Additive White Gaussian Noise (AWGN) channel. The performance evaluation of the system is determined in term of Bit Error Rate (BER) and Signal Energy to Noise Power Ratio (Eb/No). The MIMO OFDM system with Least Square channel estimation will be designed and simulated using MATLAB where the results will then be analyzed. From the results obtained, it can be said that as the QAM level increased the BER will increase too. Besides that, the performance of the system will improves as the number of transmit and receive antennas increase.