Implementation of a NOMA Downlink with SIC receiver for 2 users over SDR and GNU Radio

Non-orthogonal multiple access (NOMA) is presented as one of the most promising radio access techniques in next-generation wireless communications because compared to orthogonal frequency division multiple access (OFDMA), NOMA offers a set of potential benefits, such as increased spectral efficiency, reduced latency, high reliability, and massive connectivity. Research has shown that NOMA has the potential to be applied in various fifth-generation (5G) communication scenarios, including machine-to-machine (M2M) communications and the Internet of Things (IoT). It is because of that in this paper, a NOMA downlink with successive interference cancellation (SIC) at the receiver side for 2 users is implemented using a Software Defined Radio platform and the Universal Software Radio peripheral as a RF frontend. The objective is to analyze the system’s bit error rate based on the SNR of each user by adding noise from a RF generator; the allocation of power used in this application is 75% for the far user and 25% for a near user while using BPSK modulation for both. From the results it is concluded that Software Defined Radio (SDR) presents as an evolving and adaptable platform offering various access strategies to support multiple services, making it a viable solution for wireless technologies like 5G.