Communication-Oriented Channel Characteristics of Holographic Curvature-Reconfigurable Apertures

This letter investigates the joint impact of array curvature and mutual coupling (MC) on holographic curvature-reconfigurable apertures. An analytical framework is developed to characterize spatial correlation, coupling-aware reference directivity, and spectral efficiency. Under the small-curvature regime, we establish a relation linking inter-element distances to coupling perturbations and spatial-mode eigenvalues. Simulation results reveal asymmetric spectral-efficiency variations between transmit- and receive-side array curvature with MC, while their no-MC difference is consistent with zero under hemispherical isotropic scattering. Results based on the 3rd Generation Partnership Project clustered delay line-B channel angular/power profile, together with colored-noise sensitivity analysis, further show that the effects of curvature and receive-side coupling depend on the propagation angular distribution and receiver-noise covariance. These findings highlight the importance of jointly accounting for array geometry, mutual coupling, and receiver noise when evaluating curved holographic multiple-input multiple-output links.