Effects of PRF variation on spaceborne SAR imaging

High resolution and wide swath have always been critical criteria for SAR systems and consistently pursued. This paper investigates the utilization of pulse repetition frequency (PRF) variation in two situations: very high resolution and ultra-wide swath. It is demonstrated that by adopting varied PRF, in the former case, which corresponds to Spotlight and Sliding Spotlight modes, a much larger range cell migration(RCM) is tolerated and higher resolution is thus guaranteed, while in the latter case blind ranges are eliminated and wider swath are imaged without conspicuous degradation. The principles of PRF variation of both cases are proposed. It is shown the benefits of PRF variation include higher resolution, wider swath width and decreased azimuth ambiguity-to-signal ratio(AASR) and higher data efficiency.