Process for the digitization and linearization of a transducer with a quasi-sinusoidal periodic characteristic and corresponding apparatus

US4933888A · kind A · utility

Assignee

• COMMISSARIAT A L'ENERGIE ATOMIQUE ET AUX ENERGIES ALTERNATIVES · FR

Inventors

• Daniel Bloyet · Thaon, FR
• Christian Dubuc · Kamloops, CA
• Denis Duret · Grenoble, FR
• Jacques Lepaisant · Hérouville-Saint-Clair, FR
• Didier Robbes · Verson, FR
• Khalid Benhida · Caen, FR

Key dates

• Filing date: Apr 25, 1988
• Grant date: Jun 12, 1990
• Expiry date: Apr 25, 2008

Classification

• Technology area (CPC G): Physics
• CPC primary: G01R33/0354
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

Process for the digitization and linearization of a quasi-sinusoidal periodic characteristic transducer and the corresponding apparatus. The process consist of measuring a variation (.DELTA..phi..sub.x) of a signal (.phi..sub.x) received by the transducer in accordance with the following operations: PA0 superimposing on the signal to be measured a first auxiliary periodic signal (.phi..sub.I) of frequency F.sub.I higher than the highest frequency of the range of the signal to be measured and of amplitude substantially equal to .phi..sub.o /2 and a second auxiliary signal constituted by a periodic linear ramp (.phi..sub.R) of a frequency f.sub.R well below F.sub.I and of amplitude .phi..sub.1, the transducer thus receiving a composite signal constituted by the signal to be measured, the first auxiliary signal and the second auxiliary signal; PA0 deducing from the signal supplied by the transducer, two periodic signal V.sub.C1 and V.sub.C2, of period .phi..sub.o ; and in quadrature; PA0 measuring the level b of the second auxiliary signal when the signal V.sub.C1 reaches a predetermined state, said state having a periodicity .phi..sub.1 in the signal of V.sub.C1 ; PA0 counting the nu…