Future wireless networks and 5G communication technology aims to provide seamless connectivity for geographical areas having thousands of users within hundreds of meter radius. Emerging communication technologies, specifically, multiple access techniques have to provide enhanced capacity in order to meet this objective. power domain non-orthogonal multiple access (PD-NOMA), which is a prominent multiple access technique for 5G, fails to distinguish equidistant users around base station on the basis of power factors. To overcome this limitation and to further improve the capacity, a novel hybrid spreading and scrambling based multiple access (SSMA) technique is proposed in this paper. The proposed scheme combines power domain NOMA and multiuser shared access (MUSA). The main objective is to provide improved capacity and better performance without compromising spectral efficiency and non-orthogonality of the resources. One of the major contributions of this paper is the development of joint interference cancellation algorithm combining both successive interference cancellation and parallel interference cancellation for the proposed SSMA system. The performance of the proposed scheme is analyzed and compared with MUSA and PD-NOMA to show its superiority over both, in terms of BER, capacity, and spectral efficiency.

未来的无线网络和 5G 通信技术旨在为数百米半径内拥有数千用户的地理区域提供无缝连接。新兴的通信技术，特别是多址技术，必须提供增强的容量才能实现这一目标。功率域非正交多址（PD-NOMA）是 5G 的一种突出的多址技术，无法根据功率因数区分基站周围的等距用户。为了克服这一限制并进一步提高容量，本文提出了一种新的基于混合扩频和加扰的多址接入 (SSMA) 技术。所提出的方案结合了电源域 NOMA 和多用户共享访问 (MUSA)。主要目标是在不影响频谱效率和资源的非正交性的情况下提供改进的容量和更好的性能。本文的主要贡献之一是为所提出的 SSMA 系统开发了结合连续干扰消除和并行干扰消除的联合干扰消除算法。对所提出方案的性能进行了分析，并与 MUSA 和 PD-NOMA 进行了比较，以显示其在 BER、容量和频谱效率方面的优越性。