Abstract: A synthetic aperture radar (SAR) compensates for ionospheric distortions based upon measurement of the group delay, particularly when operating in the VHF/UHF band. The SAR is based upon a multi-input multi-output (MIMO) technique for estimating the effective ionospheric conditions, which is referred to as the group delay approach. The group delay approach is divided into a 1-dimensional (range) approach and a 2-dimensional (range and cross-range) approach. The group delay measures the effective or observed TEC, which is used to reduce the ionospheric distortion.

Abstract: A synthetic aperture radar (SAR) for a moveable platform includes an antenna, a radar transmitter and radar receiver cooperating with the antenna. A radar processor is connected to the radar transmitter and radar receiver to account for the Faraday rotation introduced by propagation through the ionosphere by estimating an individual ionospheric distortion for each received echo pulse based upon a measured Faraday rotation, and reducing the ionospheric distortion for each received echo pulse based upon the estimated individual ionospheric distortion associated therewith for providing a compensated echo pulse.

Abstract: A floating layer recovery apparatus is disclosed for selectively pumping a liquid floating on groundwater. The apparatus preferably includes a first float which is buoyant in the floating layer attached by a guide to a bottom float which has neutral buoyancy in the groundwater. A middle float is slidably attached to the guide for upward and downward movement between the first and bottom floats. The middle float being an inlet is constructed to have an effective density in the assembly such that it rests at a point where its inlet is near the bottom of the floating layer. Coiled conduits disposed above and below the bottom float carry the floating layer liquid received by the inlet to a pump disposed below. The pump then pumps the floating layer liquid from the conduit to the ground surface. In a preferred embodiment, more precise control over the level of the inlet port is achieved by means of an adjustable inlet port means.

Abstract: A floating layer recovery apparatus is disclosed for selectively pumping a liquid floating on groundwater. The apparatus preferably includes a first float which is buoyant in the floating layer attached by a guide to a bottom float which has neutral buoyancy in the groundwater. A middle float is slidably attached to the guide for upward and downward movement between the first and bottom floats. The middle float being an inlet is constructed to have an effective density in the assembly such that it rests at a point where its inlet is near the bottom of the floating layer. Coiled conduits disposed above and below the bottom float carry the floating layer liquid received by the inlet to a pump disposed below. The pump then pumps the floating layer liquid from the conduit to the ground surface. In a preferred embodiment, more precise control over the level of the inlet port is achieved by means of an adjustable inlet port means.