Improving MIMO-OFDM Performance with Convolutional Coding and Discrete Wavelet Transform

Abstract

This paper presents a new way to improve the performance of MIMO-OFDM (multiple input multiple output - orthogonal frequency division multiplexing) by reducing the Bit Error Rate (BER) using both Convolutional Coding (CC) and discrete wavelet transform (DWT). In this Paper, OFDM system was simulated and studied with three models, SISO-OFDM, MISO-OFDM and MIMO-OFDM. The final system (MIMO-OFDM) has been improved by using CC at a coding rate 1/2 and using a DWT instead of FFT and then using both CC and DWT. The communication channels used in the study are Rician and Rayleigh fading channels and the modulation technique is Binary Phase-Shift Keying (BPSK) with 64 number of carrier frequencies. The results showed that the use of both convolutional coding and discrete wavelet transform in the MIMO-OFDM system reduces the bit energy to the intensity of noise energy (Eb/N0) by 3.4 dB as the Rayleigh fading channel is used and 4.6 dB as the Rician fading channel is used when BER=10-3. The results were obtained by modeling in the MATLAB program.