PERFORMANCE BASED COMPARISON BETWEEN NOMA AND OFDMA

Abstract

The wireless communication systems have developed new multiple access technologies because of their need to deliver high data rates while connecting numerous devices and using spectrum resources efficiently. The study uses performance metrics to evaluate Non-Orthogonal Multiple Access (NOMA) and Orthogonal Frequency Division Multiple Access (OFDMA) systems under conditions that exist in actual wireless channels. The simulation framework creates a comprehensive simulation system which includes real-world elements, including path loss and Rayleigh fading and user movement and distance jitter and errors in Successive Interference Cancellation (SIC). The system uses these elements to create wireless environments which behave like real-world situations because its channel conditions change throughout time due to user movements and interference. The research process employs Monte Carlo simulations which perform multiple independent tests to achieve statistically valid research outcomes. The study evaluates key performance metrics which include sum rate, spectral efficiency, energy efficiency, fairness index, and outage probability across different user scenarios, which include various mobility levels and different SIC error rates. The research examines the performance of multiple access techniques, which operate in different network conditions while conducting an assessment of their performance capabilities and weaknesses. NOMA provides major advantages over OFDMA because it enables users to access multiple users at once through power-domain multiplexing, which results in better spectral usage and user balance. The NOMA system performs poorly when it receives either SIC errors or changes in its wireless environment because these factors result in unhandled interference that affects system operations. OFDMA enables stable communication since it uses orthogonal resource allocation to separate user channels, which leads to simpler receiver operations but results in lower spectral efficiency as more users connect to the system. The research demonstrates how organizations must balance their operational efficiency against their need to maintain network reliability and system complexity at present, which helps organizations to build advanced wireless systems for upcoming 5G networks and subsequent technologies.