Direct conversion to X band using a 4.5 GSps SiGe Digital to Analog Converter

Abstract

This work presents a new high speed, high bandwidth Digital to Analog Converter (DAC) which enables the direct conversion of wideband Radar chirp waveforms to frequencies up to band X. The component features a number of innovative design features which enable the optimization of performance in the different Nyquist zones. These include various output shaping schemes and interface methods. Preliminary results are provided which show the performance of the circuit at output frequencies greater than 7GHz. Digital chirp patterns have been created for this component and the results of these patterns output by the DAC are presented along with the ability of the component in high speed switching applications. The component's performance can result in highly flexible and waveform agile Radar signal generation systems.