Abstract: A computer-implemented method for encrypting image, wherein the image data is generated by collection of a signal, the signal having a bandwidth, and the image data comprises data corresponding to a plurality of pixels of an image, wherein each pixel has an associated phase value; and the method comprises the step of modifying each of the phase values respectively associated with each of the plurality of pixels based on a first encryption key, wherein a rate of change of phase between adjacent pixels, after the step of modifying each of the phase values, does not exceed the bandwidth.

Abstract: A computer-implemented method for encrypting image, wherein the image data is generated by collection of a signal, the signal having a bandwidth, and the image data comprises data corresponding to a plurality of pixels of an image, wherein each pixel has an associated phase value; and the method comprises the step of modifying each of the phase values respectively associated with each of the plurality of pixels based on a first encryption key, wherein a rate of change of phase between adjacent pixels, after the step of modifying each of the phase values, does not exceed the bandwidth.

Abstract: A satellite (140) for operation in orbit around the earth comprises an ADCS (131, FIG. 1) configured for mechanically steering the satellite in the azimuth direction to prolong a dwell time (1105), during which a selected target is visible from the satellite, as the satellite orbits over the target. A processor at the ground station may be configured to process raw SAR data from any of the satellites described here. The raw SAR data may be processed in a number of ways to provide image information including but not limited to forming multilook images, compiling video sequences and colour coding images.