Low Noise High Speed Camera Electronics for Cartosat-1 Imaging System

摘要

India's Space programme for cartography is aimed at up-gradation of topographic maps and utilization of natural resources for planned development of country. The Cartosat-1 satellite, launched in early May 2005, has unique features compared to previous Indian cartographic missions in providing higher resolution and along track stereoscopic imaging. The camera sensor is a linear CCD. The camera electronics is a high-speed low noise system generating stimulus for the detector operation, for processing the detector signal and for digitization in a 10-bit format. The design takes into consideration the high speed design requirements while meeting the low noise performance requirement with a goal of SNR>1024 in mixed signal environment. The noise contributions are apportioned, controlled and optimized. A low noise configuration has been evolved and accordingly camera electronics system has been developed. Detailed simulation, testing and analysis have been carried out on the designs. Consistent performance has been achieved during all the tests and the designed performance at the camera level has been validated through excellent imageries obtained from the satellite after launch.