Spaceborne Traffic Monitoring with Dual Channel Synthetic Aperture Radar Theory and Experiments

Abstract

This paper revises the theoretical background for upcoming dual-channel Radar satellite missions to monitor traffic from space. As it is well-known, an object moving with a velocity deviating from the assumptions incorporated in the focusing process will generally appear both displaced and blurred in the azimuth direction. To study the impact of these (and related) distortions in focused SAR images, the analytic relations between an arbitrarily moving point scatterer and its conjugate in the SAR image have been reviewed and adapted to dual-channel satellite specifications. To be able to monitor traffic under these boundary conditions in real-life situations, a specific detection scheme is proposed. This scheme integrates complementary detection and velocity estimation algorithms with knowledge derived from external sources as, e.g., road databases.

Performance analysis of the TerraSAR-X Traffic monitoring concept

“…Meyer et al, 2005;Hinz et al, 2005;Laika et al, 2006), although some technical and implementational improvements have been added. We include this part here in a condensed version for the sake of selfcontainedness of this paper.…”

Polarimetric time-frequency analysis of vessels in Spotlight SAR images

“…Moving targets cause perturbations in the SAR imaging process [6,10,11], due to the mismatch between the stationary filter used for focusing and the non-stationary target signal. A vessel moving with a radial velocity component is shifted from its position in the along track direction and the amount of shift is proportional to its slant range velocity.…”

Ground moving target indication and parameters estimation using a dual-frequency synthetic aperture radar

“…In practice, the system is so complex that both high hardware and computation efforts are needed in implementation [3][4][5][6][7][8][9][10]. Recently many GMTI methodologies based on a single antenna SAR or a single complex-valued SAR image, e.g., auto-focusing [11], antenna beam patten transforming [12], and SAR stacks [13], were developed and got many effective results. However, the proposed methods suffer from either a high computation effort or unsatisfactory estimate accuracy under the condition of high signal-to-clutter-plus-interference-ratio.…”