Pseudo Interpolating Arbitrary Waveform Synthesis Method For Error Analysis

Direct digital synthesis technology has been widely used in the arbitrary waveformgenerator. However, with continuous improvement of the arbitrary waveform generatoroutput frequency, the sampling rate of Digital to Analog Converter which is the keymodule in the direct digital synthesis technology has restricted the improvement of theoutput frequency. For the above problem, the paper analyzed the application of pseudointerleaving technology based on multi-DDS to arbitrary waveform generator, includingthe channel mismatch errors analysis of the pseudo interleaving process. The points ofthis paper as follows:1．The origin of errors in the pseudo interleaving process are discussed accordingthe principle of pseudo interleaving. Principle of direct digital synthesis technology isalso discussed. And the pseudo interleaving method is demonstrated in frequencydomain. What’s more, the origin of errors in direct digital synthesis and pseudointerleaving is discussed, and the error models are built.2． The hardware platform are designed based on the pseudo interleavingtechnology for errors analysis including the clock circuit, digital-analog conversion andamplitude control circuit.3．Analysis of mismatch errors between the DDS channels in frequency domain.Kinds of hold function can be adopted for waveform reconstruction in the pseudointerleaving process. This paper focuses on the errors of sampling clock phase mismatchand output waveform amplitude mismatch between the DDS channels of pseudointerleaving process in different hold functions.4． The spectrum of the output signal with phase mismatch error and amplitudemismatch errors are given in the experiment on pseudo interleaving process, and thedifferent hold functions are adopted.