Performance Analysis Of Full-duplex Massive MIMO System Based On Low Resolution ADCs/DACs And Mixed ADCs/DACs

With the rapid development of communication technology,5G technology has begun to enter commercial applications.In order to further increase the transmission speed,5G technology must overcome the shortage of spectrum resources,reduce high hardware costs,and deal with the rate decline caused by complex transmission environments.Large-scale multi-input multi-output(MIMO)technology greatly improves the transmission rate of communication system by using large-scale antenna array,and the hardware cost brought by large-scale antenna array can be reduced by equipping with low-resolution analog-to-digital converter/digital-to-analog converter(ADC/DAC)and mixed ADCs/DACs.In addition,the application of relay technology to the existing system model can deal with the situation of long-distance transmission and complex transmission environment.On the other hand,compared with half-duplex technology,full-duplex(FD)technology enables simultaneous transmission and reception of signals on the same frequency resources,which can greatly improve spectral efficiency.Therefore,this paper mainly studies the full-duplex system model equipped with the above technologies and its achievable rate.The specific research contents are as follows:Firstly,this paper studies the achievable rate of the FD massive MIMO relaying system with lowresolution ADCs/DACs over Rician fading channels.In the case of perfect channel state information(CSI),using Maximum Ratio Combining/Transmission(MRC/MRT)signal processing method,we derive the approximate expression of the achievable rate,and further analyze the impact of the quantization bit,loop interference,number of antennas,and Rician factor on the system performance.The theoretical results show that increasing the number of antennas cannot increase the rate of the system infinitely,and the achievable rate is also affected by the quantization bits.Finally simulation results verify that it is reasonable to use low-resolution ADCs/DACs in FD massive MIMO systems.Then,this paper studies the performance of FD massive MIMO system with mixed ADCs/DACs architecture under Rayleigh channel.In the case of perfect CSI,using MRC/MRT signal processing method and additive quantization noise model(AQNM),we derive approximate expressions for the uplink rates and downlink rates of the system model,and then we study the impact of three factors on system performance,including the number of antennas,loop interference,and the quantization bits.In addition,we also study the relationship between antenna mixing ratio and energy efficiency.The theoretical results show that by adjusting the mixing ratios,better system performance can also be obtained under the condition of saving power consumption,which verifies the rationality of using mixed resolution ADCs/DACs in FD massive MIMO systems.Finally,based on the existence of signal diffusion and the LOS path presence in realistic application scenarios,and considering the impact of low-resolution ADCs/DACs on CSI acquisition,this paper studies the performance of FD massive MIMO system with mixed ADCs/DACs based on Rician channel under imperfect CSI.We derive approximate expressions for the uplink and downlink rates of this system model,and further investigate the effects of Rician factor,loop interference,quantization bits,and antenna mixing ratio on the system performance in theory and simulation.Finally,we carry out simulation work related to the energy efficiency of the system,and give some suggestions on realistic deployment based on the simulation results.