Method and system for monitoring vehicle location
US4939522A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 15, 1989 |
| Grant date | Jul 3, 1990 |
| Priority date | — |
| Expiry date | May 15, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01S5/08
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Multiple vehicles located within a predefined search space are located and tracked using at least two spaced-apart transmitters. Each transmitter can broadcast an omnidirectional initialization signal and a positioning signal having a null or break in its wavefront. By rotating the positioning signal, the null will sweep the predefined search space and by detecting both the initialization signal and the null in the positioning signal, the position of each vehicle can be determined. In the preferred embodiment, the locational information from each vehicle is collected at a central location, typically in a data acquisition system or controller. In the particularly preferred embodiment, the locational information is further relied on to provide for command information for feedback control of the vehicles.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.