Passive tracking system and method
US6903685B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 1, 2003 |
| Grant date | Jun 7, 2005 |
| Priority date | — |
| Expiry date | Jul 1, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B1/7085
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
System and methods are disclosed for passively determining the location of a moveable transmitter utilizing a pair of phase shifts at a receiver for extracting a direction vector from a receiver to the transmitter. In a preferred embodiment, a phase difference between the transmitter and receiver is extracted utilizing a noncoherent demodulator in the receiver. The receiver includes antenna array with three antenna elements, which preferably are patch antenna elements aced apart by one-half wavelength. Three receiver channels are preferably utilized for simultaneously processing the received signal from each of the three antenna elements. Multipath transmission paths for each of the three receiver channels are indexed so that comparisons of the same multipath component are made for each of the three receiver channels. The phase difference for each received signal is determined by comparing only the magnitudes of received and stored modulation signals to determine a winning modulation symbol.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.