Enhancing BER performance of Coded Wi-Max OFDM System for Higher Traffic and M-order Modulations Techniques

Abstract

It is very time to investigate the impact of higher data size and traffic open coded –Wi-Max OFDM systems for futuristic 5G communication systems. This study investigated the Bit Error Rate (BER) performance of Wi-Max MIMO-OFDM systems using higher-order FFT sizes and lower-order modulation schemes. This study aims to find a balance between utilizing a higher-order FFT and selecting a relatively lower modulation order for M-PSK and QAM modulation without compromising the BER performance. A Trellis-coded interleaved OFDM system is proposed for Wi-Max higher-data-rate transmissions. The system adopts an adaptive modulation approach that dynamically adjusts the modulation scheme based on the channel conditions. Simulations were conducted in two passes to evaluate the impact of higher FFT sizes and data rates on BER performance. The first experiment iteratively increased the FFT sizes and compared the BER results for the BPSK, QPSK, and 4-QAM modulations. The second experiment investigated the impact of higher data rates on BER performance using reduced-order FFT sizes. The results showed that increasing the FFT size improved the BER performance, but required a higher SNR range. Reducing the modulation order for bigger FFT sizes allows for equivalent BER performance. When data size was raised tenfold the BER performance is improved by significant folds. The best BER of 3x10-7 was achieved for BPSK with an FFT size of 128. Overall, the study concludes that using a lower modulation order with a higher FFT size is preferred for systems with an SNR lower than 16 dB, whereas QPSK with an FFT size of 16 offers the best trade-off between data capacity and SNR requirements.