A Novel Approach to Enhance the Energy Efficiency of a NOMA Network
Abstract
:1. Introduction
2. Related Works and Motivation
 We propose a new user allocation algorithm called User Subchannel Fair Matching Algorithm (USFMA), benefiting from existing user allocation algorithms and combining their advantages. Unlike USMA, we propose an optimum channel gain compensation, sorting, and selection that can enhance the overall system capacity and performance. This algorithm has a lower computational complexity than the Exhaustive Search Algorithm (ESA) and can ensure user fairness. Moreover, the complexity of the USFMA will not increase sharply when increasing the number of superimposed users.
 Optimization of the energy efficiency of NOMA systems. We propose using the DC programming method to allocate power for end users superimposed on the corresponding subchannel. The main idea is to utilize DC programming to convert nonconvex problems into convex problems.
 Simulations of the proposed algorithm in Matlab. The simulation results confirm that NOMA systems surpass OFDM systems. Additionally, the USFMA is better than the existing USMA and CSSPA. Therefore, using DC programming to allocate power for end users can improve the system’s energy efficiency.
3. System Model
4. Problem Description
5. The SubOptimal Solution
5.1. User SubChannel Fair Matching Algorithm
Algorithm 1: User SubChannel Fair Matching Algorithm (USFMA) 

Complexity Analysis
5.2. Power Allocation by DC Programming
Algorithm 2: Power Allocation by DC Programming [46] 

6. Performance Analysis
Simulation Results
7. Conclusions
Author Contributions
Funding
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Matching Results  ${\mathit{v}}_{1}$  ${\mathit{v}}_{2}$  ${\mathit{v}}_{3}$ 

${u}_{1}$  10  [39]  22 
${u}_{2}$  [61]  54  38 
${u}_{3}$  79  55  [60] 
${u}_{4}$  171  [215]  516 
${u}_{5}$  [328]  232  1133 
${u}_{6}$  403  837  [1886] 
Simulation Parameters  Parameter Value 

Cell radius  500 m 
Minimum distance between BS and UEs  50 m 
Minimum distance between two users  40 m 
System bandwidth  5 MHz 
Maximum number of UTs  60 
Fixed circuit power [47]  1 W 
Noise power spectral density  −174 dBm/Hz 
Difference tolerance in Algorithm 2  0.01 
Compensation matrix attenuation coefficient  0.4 
Base station peak power ${P}_{BS}$  41 dBm 
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Rajab, H.; Ren, B.; Cinkler, T. A Novel Approach to Enhance the Energy Efficiency of a NOMA Network. Telecom 2023, 4, 611628. https://doi.org/10.3390/telecom4030027
Rajab H, Ren B, Cinkler T. A Novel Approach to Enhance the Energy Efficiency of a NOMA Network. Telecom. 2023; 4(3):611628. https://doi.org/10.3390/telecom4030027
Chicago/Turabian StyleRajab, Husam, Baolin Ren, and Tibor Cinkler. 2023. "A Novel Approach to Enhance the Energy Efficiency of a NOMA Network" Telecom 4, no. 3: 611628. https://doi.org/10.3390/telecom4030027