Performance analysis of a MIMO-OFDM communication system with SFBC using MSK and GMSK modulation

Abstract

The use of multiple antennas at both the transmitting and receiving end of communication channel initiates the multiple input multiple output technology (MIMO). Orthogonal Frequency Division Multiplexing, OFDM with MIMO reduces the effect of fading on transmission rate without increasing the power and bandwidth. The bit error rate (BER) performance of time and frequency selective channels can be increased by combining MIMO with space time block coded OFDM (STBC-OFDM) and space frequency block coded OFDM (SFBC-OFDM) respectively. When Alamouti space time code is used in frequency domain over OFDM subcarriers, space frequency block code is obtained.

Mostly performance of SFBC-MIMO-OFDM scheme is evaluated in Rayleigh fading environment with MPSK (M-ary Phase Shift Keying) and MQAM (M-ary Quadrature Amplitude Modulation) modulation schemes. The Minimum Shift Keying (MSK) and Gaussian Minimum Shift Keying (GMSK) modulation schemes have better energy efficiency than the MPSK and MQAM modulation schemes while using with SFBC-MIMO-OFDM schemes.

This thesis contributes in deriving and evaluating the BER expressions using SFBC-MIMO-OFDM with MSK and GMSK modulation in both Rayleigh and Nakagami-m fading environment. Also the BER expressions for MQAM and MPSK in Nakagami-m environment are evaluated. Then the receiver sensitivity is also evaluated for all the schemes. Finally the BER performances and also the receiver sensitivities are compared among all the SFBC-OFDM schemes presented in the research.