Abstract: The present invention discloses a dual function satellite imaging and communication system (10, 40, 50, 60) using a solid state mass data storage device (30) which generates and stores image data at a relatively low data rate and subsequently transmits the data at a significantly higher data rate. The dual function imaging and communication system (10, 40, 50, 60), which may be incorporated as a body mounted payload of an imaging satellite, provides a single antenna or aperture (28, 54, 62) to perform both the imaging and communication functions and simplify the imaging and communication systems of the imaging satellite by eliminating the requirement for a separately gimballed antenna and/or aperture for each system. Further, the present invention is designed to operate in a low duty cycle mode to minimize its power supply requirements.

Abstract: A technique for applying selected phase delays to an optical carrier signal, the phase delays being referenced to a radio-frequency (rf) subcarrier signal. The optical signal to be phase delayed is introduced into a phase delay network comprising multiple optical paths and multiple electro-optical switches, controllable by signals generated in switching logic. The selected delays can be introduced for purposes of data modulation, or for steering an antenna beam in a phased-array antenna. As applied to the phased-array antenna system, the invention includes a data modulator, a series of star couplers for splitting the optical carrier into multiple elemental carriers, and multiple phase shifters for applying selected phase shifts to the elemental carrier signals, to effect antenna beam steering.