Increasing the performance of arbitrary waveform generators using periodicsigma-delta modulated streams

This paper describes a new method to increase the performance of existing a rbitrary waveform generators (AWG's). By encoding the digital words using s igma-delta (Sigma Delta) techniques, it is possible to decrease the noise f loor in a narrow band while keeping the same memory requirements. Calibrati on techniques to deal with the nonidealities of the AWG are also presented and verified experimentally. Improvements in spurious free dynamic ranges ( SFDR's) of over 40 dB will be demonstrated with commercial test equipment.