Full aperture image synthesis using rotating strip aperture image

Abstract

A spinning strip aperture imaging radiometer sensor system and data processing method that is capable of synthesizing full circular aperture images from a plurality of image frames acquired by the strip aperture imaging sensor. One embodiment of the imaging system comprises a rotating strip aperture wide field of view telescope, a two dimensional detector array used to detect images in the telescope's focal plane, a rotation compensation device used to prevent rotational smear during the integration time of the detectors, a signal processor used to record a plurality of image frames of a target scene that is imaged by the telescope as it rotates around its optical axis, and a signal processor and method used to synthesize the full circular aperture image from the recorded images. The operation of the full aperture image synthesis method hinges upon the ability of the rotating strip aperture to measure all of the spatial frequencies contained in a full circular aperture image measurement. Having knowledge of the strip apertures' spatial frequency passband, and the temporal registrations of each of the recorded strip aperture images permits synthesis of the full aperture image by the sensor system and image synthesis method. Image synthesis may be accomplished in the spatial or spatial frequency domains. General and illustrative examples of the image synthesis procedure and first order noise performance predictions are described. A general form of the invention utilizes two dimensional spatial frequency information to greatly reduce the line of sight stability requirements of the telescope.