Phased-Array Beam-Diversity With Multiple Channels for Improved SAR Imaging

This paper discusses the ability of a SAR to create high-resolution images with high sensitivity in a stripmap configuration. Since geometric resolution is driven by the effective azimuth beamwidth of the antenna, it compares beam spoiling methods to beam switching methods with particular attention to the achieved SNR. It also formulates the effects of element mutual coupling on the SNR. Further, since existing systems may not be able to switch beams at a rate equivalent to the PRF, this paper also discusses a method to process beam switched data collected in a burst configuration, showing that SNR and the presence of grating lobes trade against each other as the number of pulses per burst increases. Finally, this paper investigates improvements to signal quality offered by using a multichannel system, with elements aligned in the flight direction, over a single channel system.