MATLAB Implementation for Non-Orthogonal Multiple Access Environment

In this non-orthogonal multiple access (NOMA) implementation, two users are assigned to the same subcarrier with different power allocations. The receiver utilizes Successive Interference Cancellation (SIC) technology to decode signals sequentially, where higher-power signals are decoded first and subtracted before decoding lower-power signals. This power-domain multiplexing approach enables superior performance gains compared to orthogonal schemes.

The core algorithm involves calculating optimal power allocation ratios using water-filling or gradient-based methods, typically implemented through MATLAB's optimization toolbox functions like fmincon. The program simulates key NOMA characteristics by allowing simultaneous data transmission from multiple users within the same frequency band through careful power distribution and subcarrier assignment, effectively minimizing inter-user interference while enhancing signal quality and system capacity.

The SIC module implements serial interference cancellation through iterative decoding and reconstruction of user signals, using MATLAB's communication system toolbox functions for signal detection and error correction. This sophisticated system goes beyond basic communication schemes by integrating power optimization algorithms with advanced signal processing techniques, demonstrating measurable improvements in spectral efficiency and link reliability through MATLAB-based performance metrics and BER simulations.