Transponder for use in locating avalanche victims
US4331957A · kind A · utility
Inventors
Key dates
| Filing date | Apr 18, 1980 |
| Grant date | May 25, 1982 |
| Priority date | — |
| Expiry date | Apr 18, 2000 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA63B2225/50
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A transponder adapted to be carried on the body of a person for use in locating avalanche victims is designed for cooperation with a search-transmitter and includes a receiver having a passive non-linear element which, by distortion, produces a higher harmonic from the fundamental frequency received from the search-transmitter and includes metal parts which are connected to the non-linear element and function as a receiver/transmitter antenna tuned to the frequency employed, whereby the side of the transponder facing the human body is covered with a dielectric layer the thickness of which is adjusted in accordance with a transmitted frequency of 1000 MHz and in accordance with the dielectric constant of the layer, and whereby the size of the antenna is adjusted in accordance with the dielectric constant.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.