Apparatus for measuring the characteristics of an ultrasonic wave medium
US4534220A · kind A · utility
Inventors
Key dates
| Filing date | Jan 27, 1984 |
| Grant date | Aug 13, 1985 |
| Priority date | — |
| Expiry date | Jan 27, 2004 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01S15/02
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The present invention relates to an apparatus which determines the distribution of the attenuation slope coefficient on a real time basis using the center frequency shift. The phase difference between a received signal and a reference signal is determined using EXCLUSIVE OR gates or an inverse trigonometric relation stored in a ROM. The phase difference is input to a differentiator which outputs the center frequency shift of the received signal on a real time basis. The center frequency shift is input to another differentiator which outputs the attenuation slope coefficient. Thus, the attenuation slope coefficient is determined using simple hardware and without calculating the power spectrum and the first moment.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.