The High Resolution Stereo Camera (HRSC): An Advanced-Technology Light-weight Pushbroom Camera for Planetary Orbiters

Abstract

The High Resolution Camera (HRSC) comprises 9 CCD line sensors mounted in parallel for simultaneous high-resolution, stereo, multi-color and multi-phase imaging in the pushbroom mode. The image swaths recorded by the sensors (5 panchromatic, 4 narroow-band color) can either be interpreted individually or in combination. With the present optical system (f&#61175 mm) a ground mixel size of 10 m/pixel can be achieved from a spacecraft altitude of 250 km. Witheach CCD channel containing 5184 pixels this will produce a swath width of 52 km. Gains can be selected for each CCD channel in order to adjustthe 8-bit DN output values for exposure time, the order of pixel binning and the expected signal strength. The commanding concept is flexible, so making imaging from highly elliptical orbits feasible. The (optional) use of pixel binning and image data wavelet compression makes coverage of large areas at high resolution possible.Onboard data compression as well as flat-field and dark- current calibration will be performed bya powerful processor. A data buffer with 2x256 Mbytes memory based on stacked 16 Mbit DRAMs is available. The HRSC, including camera head and the digital unit, has a totalmass of 6.5 kg. The peak power consumption in the imaging mode amounts to 16.7 W.