Passive Millimeter-Wave Ranging Using Discrete Lenses with Wave-Front Coding

This paper presents an approach to millimeter-wave passive ranging using a method that has been demonstrated in the visible range. Ranging is achieved for multiple objects by way of a receiving discrete lens with modulated amplitude and/or phase response. The result is a set of image patterns with orthogonally coded, range dependent spatial frequency content. We present simulations on a relatively small (100-element) discrete lens antenna array with a cosinusoidal amplitude mask and half-wavelength period at 94 GHz. The feasibility of the approach along with comparisons to the optical counterpart are discussed.