Surveillance system in which a reflected signal pattern is compared to a reference pattern
US4382291A · kind A · utility
79Cited by
7References
6Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Oct 17, 1980 |
| Grant date | May 3, 1983 |
| Priority date | — |
| Expiry date | Oct 17, 2000 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01S15/526
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Radiation energy is emitted intermittently to an area under surveillance and a pattern of reflections is formed. Thereafter, the pattern of reflections is statistically compared with a reference pattern which is prepared in advance. When the two patterns are different, an alarm is activated.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.