On the Impact of Residual Transceiver Impairments in mmWave RF Beamforming Systems

Millimeter wave (mmWave) communication has emerged as a key technology for achieving high data-rates and low latency in 5G networks. Radio-frequency (RF) or analog beamforming is used to provide additional (beamforming) gain to compensate for propagation phenomena in the mmWave spectrum. In this letter, we analyzed the effects of residual transceiver impairments on the performance of a single-user mmWave RF beamforming system. We derived the closed-form expressions of the ergodic capacity in both Line-of-Sight (LoS) and Non-Line-of-Sight (NLoS) channels. The derived formulas are applicable for both perfect and codebook-based beam alignment. In the former, they are exact, while in the latter are approximate, but with a high degree of accuracy. The theoretical findings are verified by Monte-Carlo simulations showing an excellent agreement.