Sampling H- & V-Polarized Antennas using a Single ADC for Digital Antenna Arrays by Exploiting Multi-Dimensional Signal Processing RF Circuits

Abstract

Digital array receivers increasingly require both H and V polarization of the incident RF waves while supporting full-band operation. A wideband ADC is required for each polarization at every location of the array, leading to 2N ADCs for N locations. The paper proposes exploiting multidimensional sparsity in the spatio-temporal frequency domain to reduce the number of ADCs from 2N to N, while supporting two polarizations and wideband RF-digital operation. By using spatiotemporal sparsity with multi-dimensional linear transforms, it is proposed to combine the H and V array signals without interference, such that, the combined array signal can be sampled using just N ADCs. This allows a modern RFSoC or array receiver with N wideband ADC inputs to process N spatial locations in an array where each location contains a cross-polarized element measuring both H and V components, doubling the information carrying capacity of the N-ADC system provided that the elements limit the field-of-view to about 60°.