MATLAB BER Simulation for MC-CDMA System with 8 Users over Nakagami and Rayleigh Channels

This MATLAB simulation evaluates the bit error rate performance of an MC-CDMA communication system supporting 8 simultaneous users under different fading conditions. The implementation includes comprehensive channel modeling for both Nakagami-m fading (with adjustable m-parameter for flexibility in describing signal fading severity) and Rayleigh fading (ideal for modeling non-line-of-sight environments). Key implementation features include: - Walsh-Hadamard codes for user separation and spreading sequence generation - QPSK modulation scheme for symbol mapping - Orthogonal frequency division multiplexing (OFDM) with cyclic prefix insertion - Channel coefficient generation using built-in MATLAB functions (rayleighchan and nakagamim for respective channel models) - Maximum ratio combining (MRC) receiver implementation for optimal signal detection - Monte Carlo simulation methodology with iterative SNR sweeping for accurate BER curve generation The code structure employs modular design with separate functions for channel initialization, signal transmission, receiver processing, and error calculation, enabling easy parameter modification and performance comparison between different fading scenarios.