# Strategy for Non-Orthogonal Multiple Access and Performance in 5G and 6G Networks
## 2 Objective of the NOMA Conception  
The spectrum and energy efficiency of wireless communication networks are greatly influenced by the use of various access strategies. Non-orthogonal multiple access (NOMA) are technologies that can increase the effectiveness of orthogonal access systems due to their compatibility with other multiple access methods, their adaptability in the use of system resources, and the simplicity with which they can connect and operate a large number of subscriber devices. Time division multiple access (TDMA) and frequency division multiple access (FDMA) are two well-established orthogonal signal separation technologies [5] employed in modern multichannel communication systems. When using orthogonal access, each user is given exclusive use of a separate signal or frequency range. Multiple users can share the same frequency or specific time in a network that employs non-orthogonal multiple access (NOMA). Furthermore, a NOMA system allows for flexible power distribution strategies to ensure a more equitable recycling of resources for users located further from the networks' epicenter. It is important to recognize that the rapid evolution of today's wireless communication networks necessitates a revaluation of traditional methods for creating such systems [5]. A rise in the number of subscribers is a higher priority in 5G and 6G wireless communication networks than it was in earlier generations, where an increase in the data transfer rate per subscriber was necessary. In 5G networks, NOMA technology was recommended particularly for mass connection of subscriber devices (IoT) where a high data transfer rate is also not essential for all users. When resources in the frequency and time domains are scarce, as they often are in orthogonal access systems, NOMA technology provides an efficient workaround [5]. NOMA standardization described in the 3 GPP report is a measuring technique that was produced by the 3 GPP working group for the NR (New Radio) standard for 5G systems [6]. It can be include many Technologies such as NOMA with pattern division (PDMA), resources spreading multiple accesses (RSMA), multi-user shared access (MUSA), multiple accesses Welch spreading multiple accesses (WSMA), and interleave-division multiple-access (IDMA). To generate NOMA signals for the uplink, the 3 GPP document [7] suggests modifying the transmitting side of the NR 5G system. The Figure 1 shows the modified transmitting side of the NOMA system based on the 5G system's standard framework. 3 GPP specifications do not represent new digital processing blocks. Current standards must be modified to add new blocks to the 5G specification. The dotted lines indicate 5G processing blocks [7]. To implement NOMA, the 5G specification must include ways for delivering subscriber group signals. Developers and equipment manufacturers choose receiver structures. Group signals can isolate non-orthogonal resources of different users and boost individual user transfer rates. Additional processing at the character, bit, or both levels is used in code-separated NOMA systems. The structural scheme in Figure 1 shows how subscribers' code sequences are created using coding, interleaving, and scrambling technologies. As shown in Figure 1, the different types of NOMA employed in 5G systems necessitate either a redesigned modulator, a new scrambling block, a new six-block interleaving, or some combination of these blocks. It describes using specific NOMA schemes, how the algorithms for producing non-orthogonal multiple access group signals on the transmitting side can result in a wide variety of new block combinations in the 3 GPP NOMA schemes. The 3 GPP standardization process studied the advantages of NOMA and ultimately decided to add NOMA and orthogonal access for uplinks [8] to the 5G standard. Although NOMA has been shown to outperform current orthogonal multiple access technologies, they do so at the expense of complexity in the algorithms necessary to receive user signals [9].