Abstract

Method and system for synthetic aperture radiometry not limited by the Van Cittert-Zernike theorem and the quasi-monochromatic assumption. A radiometer system (300) for imaging the emissions from a distribution of incoherent emission sources located within a target area comprising a first antenna (322) configured to receive a first signal (326) emitted primarily from a target area, and a second antenna (324) configured to receive a second signal (327) emitted primarily from the target area. The first and second antennas may be located at approximately the same distance from the target area (310) or at substantially different distances from the target area (310). The radiometer system (300) is configured to allow the second antenna (324) to move faster than the first antenna (322) with respect to the target area (310), with the second antenna (324) moving along a pre-determined trajectory corresponding to a synthetic aperture (430). A cross correlation receiver (330) computes a plurality of cross correlation functions as based on all relevant relative time delays between the first signal (326) and the second signal (327). The image processor (340) converts computed correlation data (332) into a plurality of complex valued radial down range profiles of the target area and further computes an image of the target area based on synthetic aperture image processing principle.

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