Phase measuring apparatus

US4066952A · kind A · utility

Assignee

• Solartron Electronic Group Limited

Inventor

• Anthony J. Ley · Los Altos Hills, US

Key dates

• Filing date: Jul 9, 1976
• Grant date: Jan 3, 1978
• Expiry date: Jul 9, 1996

Classification

• Technology area (CPC G): Physics
• CPC primary: G01R25/08
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

Apparatus for measuring the phase difference between two electrical signals Asin (wt+.theta.), Bsin (wt+.phi.), given a reference signal Vsin wt generated by the apparatus, comprises a phase lock loop for generating a clock frequency f = 360F where F is the frequency of the reference signal. This clock frequency f is then used to tune a 360 stage CCD transversal filter which is used to filter successively the two first-mentioned signals, whose phase difference is then measured by a zero intercept system. The clock frequency f is used to give phase difference in degrees. The phase lock loop comprises a 90-stage CCD to which the reference signal is applied. The output of the CCD is applied to one input of a phase sensitive detector whose other input is connected to receive the reference signal, and the control signal produced by the phase sensitive detector controls a voltage controlled oscillator whose output is applied to the clock input of the CCD.