Research On Key Technologies Of Pattern Division Division Multiple Access

Pattern division multiple access technology is a new type of non-orthogonal multiple access technology based on the joint design of the transmitter and the receiver.PDMA realizes the multiplexing of multi-user signals and orthogonal resource elements in multiple signal domains through the PDMA characteristic pattern matrix at the transmitter,and uses the successive interference cancellation algorithm to detect and separate multi-user signals at the receiver.With its unique advantages,PDMA can be well applied in different scenarios of 5G.This thesis mainly studies the related key technologies of PDMA uplink channel and downlink channel.The joint optimization of transmitter and receiver is studied in the PDMA uplink channel,and the power allocation problem is studied in the downlink channel.The research points are divided into the following two parts:First,a low-complexity and high-performance RIPDMA system based on EP algorithm is studied in the PDMA uplink channel.For the joint design of the PDMA uplink channel transmitter and receiver,a random interleaver is introduced at the transmitter,and the EP algorithm is used as the receiver algorithm to complete the system design.Compared with the traditional PDMA system,the RIPDMA system can achieve better system performance,and compared with the traditional PDMA receiver algorithm,the complexity of the EP algorithm is exponentially reduced.The experiments are carried out to verify the system performance according to the different values of the overload factor,and the influence of the PDMA pattern matrix parameters on the system performance is further studied.In the PDMA downlink channel,the power allocation scheme of joint optimization of energy efficiency and system throughput is studied.Firstly,a PDMA pattern matrix generation algorithm is researched with maximizing energy efficiency as the index.On this basis,the problem of power allocation is studied for imperfect channel state information condition.The scheme realizes the joint optimization of the PDMA pattern matrix and the power allocation problem under the condition of imperfect channel state information.The generated PDMA characteristic pattern matrix can take into account the performance of both energy efficiency and system throughput.To a certain extent,it has changed the status quo of the PDMA pattern matrix as a known condition in the study of power allocation problems.In the experiment,the above scheme is simulated and verified by using the system energy consumption and system throughput as indicators.