A Novel Super Swath Spaceborne SAR Scheme for Single Pass Observation of Large-Scale Target Area

Wide swath space borne SAR has great application value for ship situation monitoring in wide swath sea surface, global forest survey, natural disaster monitoring and earth surface deformation measurement [1]. Traditional space borne SAR uses ScanSAR or TOPS to achieve wider imaging swath. For example, German TerraSAR-X [2] can achieve an imaging swath of 100km under the 18 meter resolution. ESA's Sentinel-1 [3] can achieve the imaging swath of 400km at a 20~40 meter resolution. In order to solve the contradiction between resolution and range imaging swath, Currie and Brown proposed the DPCA Technology [4]. Suess proposed HRWS Technology (taking advantage of SCORE method) [5], which can further enhance the imaging width on the premise of maintaining the resolution. At the same time, Freeman proposed a SweepSAR technique for reflector antennas to improve the width of the imaging swath [6]. In this paper, a Space borne SAR design method based on DPCA and SweepSAR is proposed, and the optimal antenna size design method suitable for wide swath imaging mode is given. A design scheme of the phased array antenna based on the GaN TR component technology and the fast switching beam control unit technology during the radar echoes receiving window is designed. Finally, through simulation, the width of the sun-synchronous orbit satellites, this design can achieve one-day revisit under the condition of a proper optimization of satellite orbit. In addition to a few countries such as Russia, Canada, USA, China, India and other big countries, it can nearly achieve 100% coverage and imaging of most of countries' territory in only one passing by, and has a very vast application prospect.