Direct conversion techniques using high speed data converters for SAR

摘要

SAR equipment can now benefit from direct conversion techniques. This paper will present some new components which facilitate direct conversion to and from Land S bands, these include : Single core, 10 and 12 bit Analog to Digital converters (ADC) with a sample rate of 1.5GSps and an analog bandwidth of 2.3GHz giving excellent performance in the L band; A Digital to Analog converter (DAC) with a 3GSps sample rate and an analog output bandwidth limit of 7GHz. This allows direct conversion techniques up to `C' band. The component has a number of different output modulation schemes and these are used to optimize the system performance depending on the frequency used. These components will be described in detail and applications using these components will be highlighted.