Hyperparameter‐Free Maximum Versoria Criterion Based Channel‐State Acquisition for mmWave Hybrid MIMO With Hardware Impairments

ABSTRACT Millimetre wave (mmWave) multiple‐input multiple‐output (MIMO) has emerged as a promising physical layer solution to address traffic demands in beyond 5G wireless communication systems. However, modern signal processing techniques for mmWave hybrid MIMO systems fall short of addressing the performance degradations due to residual transceiver hardware impairments (HIs). This paper thus considers a mmWave hybrid MIMO system with residual HIs. Using Bussgang decomposition, the residual transceiver HIs are modelled as an additive non‐Gaussian noise that severely affects the received pilot and information signals, which makes channel state acquisition challenging. In this context of channel‐estimation over non‐Gaussian noise due to HIs, this work presents a hyperparameter‐free maximum Versoria criterion (MVC)‐based channel estimation technique. In details, the MVC‐based channel‐estimator is rendered hyperparameter‐free by proposing a sampling rule for its spread parameter and a gradient descent‐based optimisation for its shape parameter . Finally, simulations are presented to show the generalisation and scenario‐invariance of the proposed MVC‐based channel‐estimator. The analytical expression for steady‐state misadjustment is also derived and validated by simulations.