To achieve the advantages provided by massive multiple-input multiple-output (MIMO),\na large number of antennas need to be deployed at the base station. However, for the reason of cost,\ninexpensive hardwares are employed in the realistic scenario, which makes the system distorted\nby hardware impairments. Hence, in this paper, we analyze the downlink spectral efficiency in\ndistributed massive MIMO with phase noise and amplified thermal noise. We provide an effective\nchannel model considering large-scale fading, small-scale fast fading and phase noise. Based on the\nmodel, the estimated channel state information (CSI) is obtained during the pilot phase. Under the\nimperfect CSI, the closed-form expressions of downlink achievable rates with maximum ratio\ntransmission (MRT) and zero-forcing (ZF) precoders in distributed massive MIMO are derived.\nFurthermore, we also give the user ultimate achievable rates when the number of antennas tends to\ninfinity with both precoders. Based on these expressions, we analyze the impacts of phase noise on\nthe spectral efficiency. It can be concluded that the same limit rate is achieved with both precoders\nwhen phase noise is present, and phase noise limits the spectral efficiency. Numerical results show\nthat ZF outdoes MRT precoder in spectral efficiency and ZF precoder is more affected by phase noise.
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