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      METRATEK radars and software processing packages provide all forms of Synthetic Aperture Radar (SAR) imaging, including:

      Downrange resolution is achieved by transmitting a broad band waveform, either a series of pulses that are stepped in frequency or frequency chirp within each pulse, or a combination of both. The resulting resolution is equal to 15 centimeters divided by the bandwidth in GHz.  It is not unusual for METRATEK radars to employ waveforms with as much as 10 GHz of  bandwidth when very high resolution is required, although typical chirps are in the 1-4 GHz range.

      Cross-range resolution is achieved by moving the radar (SAR) or the target (Inverse SAR, or ISAR) through a range of aspect angles while recording the coherent radar return. After SAR processing. the cross-range resolution is given by half the radar wavelength divided by the sine of the angular sector over which the target data is processed. Resolution is one-half wavelength per radian of aspect angle change in spotlight SAR, where the antenna is kept pointed at the target. In strip-map SAR, cross-range resolution is limited by the antenna beam width if it is less than the processed angular sector.

      Two-dimensional SAR Imaging is performed by using a high-resolution waveform to provide downrange resolution and moving the antenna (SAR) or target (ISAR) to generate resolution in cross-range. The result is an image that appears in the plane perpendicular to the axis of target or antenna motion. The image above was collected on Burt Rutan's ARES aircraft. The colors represent radar cross section on a logarithmic scale. The plots on the right are the total radar cross section of the portions of the image inside the colored boxes, plotted as in dB vs aspect angle. The images below are a Long-EZ (left) and a Learjet (right).