Warning apparatus using microwaves
US4334214A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 18, 1980 |
| Grant date | Jun 8, 1982 |
| Priority date | — |
| Expiry date | Jun 18, 2000 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG08B13/2491
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A warning apparatus comprises a Gunn oscillator, a transmitting antenna, a receiving antenna, a detector, and a comparator which produces a detecting signal when the output signal from the detector is belowed a reference level. The warning apparatus further comprises a drive circuit for applying a rectangular pulse voltage to the Gunn oscillator, a band-pass filter allowing only a microwave with the transmitting frequency band of microwaves received by the receiving antenna to pass therethrough, and a signal generator for applying the reference signal, which changes in accordance with the output signal of the detector, to the comparator.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.