An encounter with pursuit monostatic applications of TanDEM-X mission

From October 2014 to February 2015, TerraSAR-X and TanDEM-X satellites operated in a Pursuit Monostatic formation, in which independent images were acquired with a temporal separation of 10 seconds, and an along track baseline of approximately 76 km, at a maximum effective baseline of 750 m [1]. In this phase, in order to support interferometric acquisitions of the same footprint on the ground, TanDEM-X orbit was adjusted, while TerraSAR-X remained unaffected relative to its reference orbit. In preparation for a potential multi-mission Pursuit Monostatic formation following the end of the TanDEM-X science phase between TanDEM-X satellites and Spanish satellite PAZ [2], several new imaging acquisition arrangements with the current operational modes were investigated. The performances and effectiveness of these new SAR applications were evaluated. In this paper we provide a brief summary of these new configuration scenarios. Primary examples demonstrate the potential of the monostatic formation for new imaging arrangements, such as wider swath or longer images by combination of two parallel or adjacent SAR scenes. Also, immediate repeat pass interferometric acquisitions for creation of digital elevation models (DEM) with minimal temporal delay were successfully tested. In here, in addition in comparison to TanDEM-X bistatic configuration, the characteristic and limitation imposed by the 10 seconds delay of the repeat-pass temporal decorrelation [3] is examined in a case scenario acquired over forested areas.