Measuring apparatus utilizing spectrum profile
US4545250A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 19, 1984 |
| Grant date | Oct 8, 1985 |
| Priority date | — |
| Expiry date | Mar 19, 2004 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01S7/52077
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
This invention relates to an apparatus for measuring of imaging the characteristic structure of a medium utilizing the power spectrum profile of received signal waves, which are derived from an incident beam pulse of ultrasonic waves or other waves that are incident on the object to be measured and which travel through the object by transmission and reflection. They are affected by various acoustic characteristic structures of the object, and information about the structure can be attained by the procession of the signals received with a transducer. The processing is performed by taking their cepstrum, and filtering the slowly varying cepstra including that of the target Gaussian shaped pulse signal from the fast varying cepstra. The filtered cepstrum is processed further by the inverse transformations to the power spectrum derived from said filtered cepstrum. The influence of line cepstra remaining still in the lower frequency and the frequency dependence of the reflection indices of the structure to the derived power spectrum is eliminated by the distortion indices of said derived power spectrum. Thus the travelled power spectrum is recovered as a virtual spectrum, expected when …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.