Development and Characterization of a Low Distortion Dual-Channel Arbitrary Waveform Generator

Abstract

This paper develops a dual-channel arbitrary waveform generator (AWG) with high accuracy and low distortions for precise measurement and metrology applications. The AWG incorporates the direct digital synthesis (DDS) for waveform generation, a master-slave collaborative configuration for crosstalk elimination, and a harmonic cancellation unit for spectral purity improvement. Moreover, a quantum-based characterization system to evaluate its performance is presented, where a digitizer PXI-5922 with high resolution and low noise floor automatically switching between the quantum voltage standard and AWG to remove the gain drift of the measurement electronics. In order to accelerate the discrete Fourier transform (DFT) calculation when analyzing the pulse pattern of the quantum voltage standard, we decompose one-dimensional (1D) digital patterns into two-dimensional (2D) digital patterns. Measurement results show that the AWG developed in this paper has a high purity with a spurious-free dynamic range (SFDR) better than 96 dB and an amplitude stability of $\lt 3 \times 10^{-5}$.