| Abstract: | The future of 5th Generation and 6th Generation wireless networks is inescapable. Every second of human life depends on technology. Every day, millions of wireless IoT devices are getting activated and getting connected to wireless networks. That requires the spectrum efficiency and the bandwidth to the users should be increased for seamless connectivity considering low latency and being highly reliable. But this is not possible in traditional techniques that are been used till now. The propagation medium plays a major role in the field of communication networks. The strength of the signal transmitted depends on the properties of the medium. In a practical scenario of wireless communications, the strength of the transmitted signal depreciates during the transmission. Therefore, the quality of the signal received will not be the same as transmitted. One of the primary reasons for this situation is the rigid obstacles that are present between the source and destination. The recent invention of Reconfigurable Intelligent Surfaces (RIS) has opened wide opportunities for explorers to learn how to control the radio waves in any propagation medium. The RIS can help eradicate the adverse consequences of natural wireless propagation. Non-Orthogonal Multiple Access (NOMA) can provide multiple user connectivity using different power coefficients in the identical time, and frequency. Depending on the position of the user, the power levels are allocated, and the weak user gets more power compared to the strong user, enabling the best communication possible. The important point to be noted is that this technique can handle massive device connectivity while providing efficient spectrum utilization, low latency, and high reliability.Cognitive radio networks have been a great addition to the recent technologies as their ability to enhance spectrum utilization and sharing of networks among two groups, primary users, and secondary users. Though the working of the CRN proves to be efficient enough, there are major issues that need to be addressed like limiting the interference caused due to the two networks and power consumption during the transmission.Therefore, motivated by these potential emerging technologies, in this research, I study the integration of CRN with RIS-aided NOMA networks and the RIS-aided NOMA system. The analytical expression has been derived for the outage performance and throughput of the two proposed systems. In the CRN-assisted NOMA-aided RIS network, the primary findings involve the analysis of the outage probability and throughput of the system. Whereas in NOMA-aided RIS system, the primary findings involve analysis of outage performance of the users individually and throughput of the system, and the effect of role of the number of meta-surfaces in RIS, transit power at the base station, and power allocation factors of the NOMA users. Results yield that implementation of CR in RIS-aided NOMA system proves to efficient while considering the interference caused from the primary network. Whereas, from traditional RIS-aided NOMA system, it is manifested that number of meta-surfaces and transmit SNR play a vital role in enhancing the system performance. Both the proposed systems have proven itself that NOMA outperforms the traditional Orthogonal Multiple Access (OMA) technique.
The future of 5th Generation and 6th Generation wireless networks is inescapable. Every second of human life depends on technology. Every day, millions of wireless IoT devices are getting activated and getting connected to wireless networks. That requires the spectrum efficiency and the bandwidth to the users should be increased for seamless connectivity considering low latency and being highly reliable. But this is not possible in traditional techniques that are been used till now. The propagation medium plays a major role in the field of communication networks. The strength of the signal transmitted depends on the properties of the medium. In a practical scenario of wireless communications, the strength of the transmitted signal depreciates during the transmission. Therefore, the quality of the signal received will not be the same as transmitted. One of the primary reasons for this situation is the rigid obstacles that are present between the source and destination. The recent invention of Reconfigurable Intelligent Surfaces (RIS) has opened wide opportunities for explorers to learn how to control the radio waves in any propagation medium. The RIS can help eradicate the adverse consequences of natural wireless propagation. Non-Orthogonal Multiple Access (NOMA) can provide multiple user connectivity using different power coefficients in the identical time, and frequency. Depending on the position of the user, the power levels are allocated, and the weak user gets more power compared to the strong user, enabling the best communication possible. The important point to be noted is that this technique can handle massive device connectivity while providing efficient spectrum utilization, low latency, and high reliability.Cognitive radio networks have been a great addition to the recent technologies as their ability to enhance spectrum utilization and sharing of networks among two groups, primary users, and secondary users. Though the working of the CRN proves to be efficient enough, there are major issues that need to be addressed like limiting the interference caused due to the two networks and power consumption during the transmission.Therefore, motivated by these potential emerging technologies, in this research, I study the integration of CRN with RIS-aided NOMA networks and the RIS-aided NOMA system. The analytical expression has been derived for the outage performance and throughput of the two proposed systems. In the CRN-assisted NOMA-aided RIS network, the primary findings involve the analysis of the outage probability and throughput of the system. Whereas in NOMA-aided RIS system, the primary findings involve analysis of outage performance of the users individually and throughput of the system, and the effect of role of the number of meta-surfaces in RIS, transit power at the base station, and power allocation factors of the NOMA users. Results yield that implementation of CR in RIS-aided NOMA system proves to efficient while considering the interference caused from the primary network. Whereas, from traditional RIS-aided NOMA system, it is manifested that number of meta-surfaces and transmit SNR play a vital role in enhancing the system performance. Both the proposed systems have proven itself that NOMA outperforms the traditional Orthogonal Multiple Access (OMA) technique. |
