Automatic vehicle identification system capable of vehicle lane discrimination
US5675342A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 30, 1995 |
| Grant date | Oct 7, 1997 |
| Priority date | — |
| Expiry date | May 30, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG08G1/017
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A method of identifying an object and determining in which of at least two areas the object is located is disclosed. The method includes the steps of: focusing a first directional antenna (18) on a first area (28a), focusing a second directional antenna on a second area (28b), transmitting a first field strength pulse (44) from said first directional antenna (18), transmitting a second field strength pulse (46) from said second directional antenna (18), and comparing in a transponder (14) the first field strength pulse (44) to the second field strength pulse (46) to determine in which of the two areas (28a,28b) the transponder (14) is located. Other devices, systems and methods are also disclosed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.