Beam-Domain Channel Analysis for B5G Communication Systems Using OAM Beamforming

This paper presents a novel Wideband BeamDomain Channel Model (BDCM) tailored for cellular communication systems using massive multiple-input multiple-output (MIMO) with Uniform Circular Arrays (UCAs) in accelerating vehicular scenarios. The proposed model transforms the Geometry-Based Stochastic Model (GBSM) into the BDCM framework using beamforming matrices to enable efficient beam sampling. The derived channel model incorporates Doppler shifts, delays, and acceleration-induced effects to capture dynamic vehicular environments accurately. The paper further derives steering vectors, beam sampling vectors, and Orbital Angular Momentum (OAM) wave vectors specific to UCA configurations, employing far-field assumptions and Bessel function approximations. Simulation results validate the model's performance, highlighting its potential for next-generation communication systems involving dynamic and high-mobility scenarios.