Analysis of the efficiency of using non-orthogonal multiple access (NOMA) methods in broadband radio communication networks

It is known that the use of Non-Orthogonal Multiple Access (NOMA) methods can improve the spectral efficiency and capacity of communication networks. However, in the presence of nonlinear distortions or synchronization issues, the orthogonality of user signals within a CDMA group is disrupted, leading to inter-channel interference and a reduction in interference immunity as the number of users increases. This must be taken into account when analyzing the interference immunity in broadband radio communication networks. The paper presents simulation results demonstrating the possibility of using orthogonal synchronous code division multiple access in combination with non-orthogonal multiple access, where the system's interference immunity is determined solely by the characteristics of NOMA. The influence of power distribution among users on the network's interference immunity, depending on their distance, is shown. For the analysis, mathematical models and MATLAB implementations were used, enabling the study of key system parameters, including bit error rate (BER), capacity, and power allocation strategies. The results demonstrate that the proposed approach allows for effective analysis and optimization of NOMA systems, taking into account the impact of nonlinear distortions and power distribution. Examples of calculations are provided, confirming the feasibility of using NOMA in broadband radio communication networks.

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