Comparative spectrum trace method and apparatus for detecting transmitters
US7058530B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 13, 2004 |
| Grant date | Jun 6, 2006 |
| Priority date | — |
| Expiry date | Aug 15, 2024 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01S7/021
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An improved method and system for detecting covert surveillance devices uses frequency spectrum traces produced by a spectrum analyzer. The electromagnetic spectrum is scanned in a reference area to produce a reference frequency spectrum trace. The electromagnetic spectrum is then continuously scanned in a nearby target area to produce a peak hold frequency spectrum trace. The reference frequency spectrum trace is then subtracted from the peak hold spectrum trace to produce a comparative frequency spectrum trace. Peaks in the comparative frequency spectrum correspond to signals that are unique to either the reference area or the target area or transitory in nature. Statistical analysis is performed on subsequently obtained frequency traces to identify any changes in the frequency traces.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.