Study On Application Of MIMO-NOMA Technology In Next-Ggeneration Wireless Cellular Networks

In recent years,with the huge business demands generated by the Internet of Things and mobile Internet,there is an urgent need for the next-generation mobile communication network that can meet the requirements of massive access,high system capacity,and high transmission rate.Therefore,research on 5G mobile communication technology has been in full swing around the world.Among them,the power domain's non-orthogonal multiple access technology(Power Domain Non-Orthogonal Multiple Access,PD-NOMA)is widely used in the industry due to its excellent frequency utilization efficiency and its structure is more simple and easy than other non-orthogonal multiple access technologies.The PD-NOMA technology adds a new resource plane-power domain based on the original frequency domain,time domain,and code domain,and the newly added resources can be re-multiplexed on the original non-separable minimum resource block to increase the number of users.The purpose of the number,corresponding to the use of serial interference cancellation technology at the receiving end to eliminate the new power interference to properly detect the original signal.MIMO technology is widely used in 4G networks and it can greatly improve system capacity.Therefore,the combination of MIMO technology and PD-NOMA technology is very worthy of research and analysis.In this paper,the performance of PD-NOMA system under different channel conditions and different modulation modes is simulated and analyzed.On the other hand,PD-NOMA and MIMO technologies are combined to simulation and verification.The paper first introduces the basic principles of PD-NOMA technology.Taking two users as examples,it analyzes the difference in system capacity of PD-NOMA's OFDMA system exist in 4G network,and makes a precise analysis.The system gain brought by the PD-NOMA system is verified.Subsequently,key technologies such as power allocation and signal detection of the PD-NOMA technology are introduced.Finally,the relevant technical principles of MIMO are briefly described.Then the paper describes the workflow of PD-NOMA in a modular way,and builds a downlink-system-level simulation platform based on two users.In the PD-NOMA system,different channel models and modulation modes are switched for comparison and analysis.The EPA channel suffers from a long deep fading time,and the BER performance is worse than the other two channel models.It verifies that regardless of the channel condition or modulation mode,the edge user receives the better signal quality as owned more power by the system allocates.Finally,on the basis of previous analysis,the two main transmission modes of MIMO are described in detail and combined with the already established PD-NOMA simulation system.Using the combined simulation platform,the spatial multiplexed PD-NOMA system and the transmission diversity PD-NOMA system are simulated and analyzed.Through simulation,the combination of MIMO and PD-NOMA is compared with a single PD-NOMA system.The system throughput has been significantly improved.