A phase delay calibration method in digital bandwidth interleaving acquisition system

Area of Science:

• Electrical Engineering
• Signal Processing
• Data Acquisition Systems

Background:

• Digital Bandwidth Interleaving (DBI) extends data acquisition bandwidth.
• Phase delay calibration between subbands is critical for signal reconstruction in DBI.
• Existing methods struggle with outliers from phase noise and jitter.

Purpose of the Study:

• To develop a robust regression algorithm for precise inter-subband phase delay calibration in DBI systems.
• To improve signal reconstruction performance by mitigating phase misalignment.
• To enhance the anti-noise capability of ultrahigh-speed acquisition systems.

Main Methods:

• Modeling inter-subband phase delay calibration as a robust regression problem.
• Proposing a robust regression algorithm using overlapping-band phase difference for calibration.
• Estimating linear phase delay and phase offset while resisting outliers.

Main Results:

• The proposed algorithm effectively compensates for inter-subband phase misalignment.
• Spurious-free dynamic range (SFDR) improved from 58.73 dBc to 63.94 dBc.
• Maintained an effective number of bits (ENOB) of 6.12b at a 16 GHz input.

Conclusions:

• The robust regression scheme precisely calibrates phase delays in DBI systems.
• The method enhances SFDR and maintains ENOB, proving effective for ultrahigh-speed acquisition.
• The scheme minimizes hardware complexity and improves anti-noise capability.