Noise controller for automatically detecting and attenuating break noise in a portable hand held doppler fetal heart beat probe
US5630418A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 12, 1996 |
| Grant date | May 20, 1997 |
| Priority date | — |
| Expiry date | Jun 12, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01S15/58
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A noise controller for use in a probe in a hand held ultrasonic Doppler fetal heart beat detection and monitoring system where the probe includes a crystal for generating an input signal as a function of the ultrasonic energy in received ultrasonic wave and a detector for generating a first signal from the input signal. The noise controller comprises a volume controller for receiving the first signal and for processing the first signal to produce an analog signal as the output of the probe. A detector generates a second signal whenever break noise is detected in the first signal. A muting circuit immediately lowers the amplitude of the analog signal upon detection of break noise by the detector thereby substantially attenuated in the analog signal the break noise which occurred in the first signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.