esults 5.4.1 Power-Domain NOMA 5.4.1.1 Superposition Modulation (SPM) 5.4.1.2 Successive Interference Cancellation (SIC) 5.4.1.3 Simulation Results 5.4.2 Code-Domain NOMA 5.4.2.1 Sparse Code Multiple Access (SCMA) 5.4.2.2 Message Passing Algorithm (MPA) 5.4.2.3 Simulation Results 5.4.3 Realistic Transmission Over the Rayleigh Fading Channel 5.4.3.1 System Models 5.4.3.2 Simulation Results Conclusion References INTRODUCTION There are two methods for NOMA techniques. The two techniques are known as code domain and power domain [1]. To increase the users' detection and for the minimization of symbol error rates, the CD-NOMA uses random-Gaussian codes at the transmitter and compressive sensing on the receiving end. Moreover, because the transmitted signal is sparse, low-density spreading coding with CMDA (LDS- CDMA) and LDS-aided OFDM can be used (LDS-OFDM). In the power-domain NOMA (PD-NOMA), several user signals are jointly superimposed to utilize a DOI: 10.1201/9781003368311-5 5G Wireless Communication System in Healthcare Informatics Power Domain Code Domain LDS CDMA LDS OFDM FIGURE 5.1 The main NOMA schemes classifications. similar (frequency/time/code) resource by designating separate power-levels for each user. Likewise, dirty paper coding or SIC is used to decode the users' communication signals at the receiving end [2-3]. Figure 5.1 depicts the classifications of NOMA techniques. In this chapter, we will discuss and analyze the two techniques used in NOMA, Firstly, we will analyze the power-domain NOMA (PD-NOMA) in a real life trans- mission scenario then we will analyze the code-domain NOMA (CD-NOMA) in the same scenario. A literature review will be presented in Section 5.3. While in Section 5.4, the proposed system model and its result will be discussed. Finally, our conclu- sion will be offered in Section 5.5. 5.2 OBJECTIVES The main objectives of the chapter are as follow: 1. To assess the PD-NOMA system's effectiveness and performance. 2. To assess the CD-NOMA system's effectiveness and performance. 3. 