Amplitude detecting device
US5922964A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 24, 1997 |
| Grant date | Jul 13, 1999 |
| Priority date | — |
| Expiry date | Jun 24, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R19/00
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The phase controlling circuit 1 controls the phase of the input sinusoidal signal S1 to generate first and second sinusoidal signal S1 and S2 which have different phases of 90.degree. shifted from each other. The signal generating circuits 2a and 2b square the first and second sinusoidal signal S1 and S2 to generate first and second squared sinusoidal signals S1.sup.2 and S2.sup.2, respectively. The squared sinusoidal signals S1.sup.2 and S2.sup.2 are added by the signal adding circuit 3, thereby generating the added output S3 which is an amplitude of the input sinusoidal signal S. The phase controlling circuit 1 comprises 90.degree. phase shift circuits 11 and 12 which have a common signal input terminal and the respective signal output terminals. The 90.degree. phase shift circuit is composed of an all-pass filter whose central frequency is set to be f0-.DELTA. f so as to generate the first sinusoidal signal. The second 90.degree. phase shift circuit is composed of an all-pass filter whose central frequency is set to be f0+.DELTA. f so as to generate the second sinusoidal signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.