Performance Analysis of MIMO-OFDM System Using Different Modulation Schemes Under Different Fading Channels

The growing necessity for high-speed and dependable wireless communication has facilitated the implementation of MIMO-OFDM systems. The MIMO (Multiple Input Multiple Output) technology enhances data transmission rates by employing spatial multiplexing, which allows for the simultaneous transmission of multiple independent data streams within the same frequency band. At the same time, OFDM enhances spectral efficiency by dividing a wideband channel into multiple orthogonal subcarriers, allowing parallel transmission of lower-rate signals. The combination of MIMO and OFDM mitigates multipath fading by leveraging spatial diversity and reducing ISI through cyclic prefix insertion. This paper systematically evaluates the performance of various modulation schemes in MIMO-OFDM systems under AWGN, Rayleigh, and Rician fading channels. The key performance metrics are evaluated for modulation schemes such as M-PSK and M-QAM. The findings demonstrate that BPSK attains the minimal BER and PAPR, rendering it appropriate for energy-efficient and error-resistant applications, whereas higher-order QAM schemes offer enhanced spectral efficiency but are more vulnerable to noise and fading effects.