Processing and precoding in pd-noma system
Vitaly B. Kreyndelin, L. A. Varukina · T-Comm - Телекоммуникации и Транспорт · 2024
In mobile radio communication systems, access techniques utilizing orthogonal separation of available communication channel resources are now widely used. A capacity of such networks depends on a size of an orthogonal resource ensemble of the carrier. To increase a capacity and a number of users simultaneously accessed the networks a perspective technology of non-orthogonal multiple access might be implemented, the technology enables multiple users connected to the same orthogonal time-frequency channel unit. This technology eliminates a restriction on a number of simultaneously multiplexed user signals which arises from the size of an orthogonal resource ensemble. The paper focuses on the mobile system utilizing a new multiple access technology which is non-orthogonal multiple access. The system under study at the transmitting end of the base station employs precoding, which is based on Zero Forcing and Minimum Mean Square Error methods, it enables decorrelation of users to improve system performance. Well known demodulation algorithms are applied at the user receivers, which are Successive Interference Cancellation and Maximum Likelihood. Non-Orthogonal Multiple Access system using with the processing options above provides a gain in terms of users over traditional Orthogonal Multiple Access system.