Narrowband based navigation scheme
US6300904A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 9, 1999 |
| Grant date | Oct 9, 2001 |
| Priority date | — |
| Expiry date | Jun 9, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01S13/878
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Multiple pulses of narrow band signals of varying frequency are detected by multiple spaced apart receivers such that average time difference of arrivals of the signals from an item to be located are determined. The average time differences are used to calculate a position of the item to be located with a desired accuracy, such as within one meter in one embodiment. One of multiple receivers or rangers initiates a location process by transmitting a sync pulse. The sync pulse is received by a scout and other rangers. The scout is a small robot which acts as a transponder, sending out its own narrow band return pulse in response to the sync pulse. Each ranger then determines a difference in time between the sync pulse it receives and the return pulse generated by the scout. The location process is then repeated again at different selected narrow band frequencies, and an average of the difference in time at each ranger is determined. Each ranger is networked together via a standard wireless network, and also obtains position information via standard GPS methods. An iterative calculation of the location of the scout is used to improve an estimated position solution. Time difference of …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.