Passive Three-Dimensional Spatial-Spectral Analysis Based on k-Space Tomography

A 2D distributed-aperture imaging system paired with a newly developed imaging modality, k-space tomography, is presented for detection of radio waves' frequency and angle of arrival in azimuthal and elevation directions through coherent optical processing. This technique uses fiber-length dispersion in conjunction with a distributed antenna array to provide unique spatio-temporally encoded charge-coupled device (CCD)-captured interferograms, from which a computational tomographic reconstruction of the RF signal environment at newly allocated 5G bands can be obtained.