Friend-foe interrogation method and a system using this method
US4814769A · kind A · utility
18Cited by
6References
13Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Dec 6, 1985 |
| Grant date | Mar 21, 1989 |
| Priority date | — |
| Expiry date | Dec 6, 2005 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01S13/78
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
For carrying out an interrogation a position modulated laser light wave is used. A key word is displayed in an interrogator and coded in accordance with a cyclic code, for example Golay's code. This coded key word is used for modulating the laser wave. In the responder the same key word is displayed and coded in the same way. After reception and demodulation each message is compared in a correlation circuit with the local reference word. The correlation method used allows parasite pulses to be taken into account and the word received to be validated with a given security threshold.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.