High-Precision ADC Spectrum Testing under Non-Coherent Sampling Conditions

Area of Science:

• Electrical Engineering
• Signal Processing
• Measurement Science

Background:

• Coherent sampling is crucial for high-precision analog-to-digital converter (ADC) spectrum testing.
• Non-adherence to coherent sampling in spectrum analysis leads to spectral leakage and inaccurate test results.

Purpose of the Study:

• To develop a robust algorithm for accurate ADC testing that circumvents the need for coherent sampling.
• To eliminate spectral leakage and improve the precision of spectrum analysis in ADC testing.

Main Methods:

• A combined four-parameter sine-curve-fitting algorithm was developed for non-coherent sampling.
• The algorithm fits amplitude, initial phase, and frequency parameters of a sine wave.
• Reconstruction of test data by calculating and replacing with a coherent sine wave.

Main Results:

• Simulations confirmed the algorithm's functionality and robustness.
• The algorithm successfully processed and analyzed measured data from commercial high-precision ADCs.
• Accurate ADC parameter testing was achieved under relaxed test conditions.

Conclusions:

• The proposed algorithm effectively eliminates the requirement for coherent sampling in ADC testing.
• The method demonstrates superiority and effectiveness for precise ADC parameter evaluation.
• This scheme offers a more flexible and accurate approach to spectrum testing for high-precision ADCs.