Nuisance cell phone locator

• US 20040018845A1
• Filed: 04/15/2003
• Published: 01/29/2004
• Est. Priority Date: 09/24/1999
• Status: Active Grant

• Current Assignee: Kroll Family Trust
• Original Assignee: Kroll Family Trust
• Inventors: Kroll, Mark W.
• Granted Patent: US 7,444,154 B2
• Time in Patent Office: Days
• US Class Current: 455/456.1
• CPC Class Codes: G01S 5/14 Determining absolute distances from a plurality of spaced points of known location

Abstract

This invention covers the use of multiple internal antennas to locate a nuisance cell phone which is being inappropriately operated. For a largely 1-dimensional layout like an airplane, an embodiment teaches the location being done by using differential timing teaches the use of either differential timing or a bearing angle technique. For a largely 2-dimensional layout, such as a theater, the invention uses either differential timing or a bearing angle approach.

Claims

1. ) A method of locating nuisance cellular telephones consisting of the steps of:

a) installing at least two radio frequency direction finding systems inside of a public building

b) monitor for signals with cellular telephone frequencies

c) calculating an angle-of-origin to a source of such frequencies

d) calculating the location of the source from the angles-of-origin.

2. ) The method of claim 1 in which the location calculation involves the step of determining the intersection of the angle-of-origin lines.

3. ) The method of claim 1 in which the location calculation involves the step of calculating a seat number for the source.

4. ) The method of claim 1 in which the angle-of-origin is determined by detecting the phase difference between two antennas.

5. ) The method of claim 1 in which the angle-of-origin is determined by the pseudodoppler technique.

6. ) The method of claim 1 in which the angle-of-origin is determined by the amplitude response technique.

7. ) The method of claim 1 in which the angle-of-origin is determined by phase differential-to-amplitude response.

8. ) The method of claim 1 in which the angle-of-origin is determined by phase interferometry.

9. ) The method of claim 3 in which the seat number is displayed overhead for the audience.

10. ) A system for locating a nuisance cellular telephone in a public place comprising:

a) a first direction finding unit,

b) a second direction finding unit,

c) a controller operably connected to the two direction finding units, and

d) a display operably connected to the controller, such that the system can calculate the location of the nuisance cellular telephone.

11. ) The system of claim 10 in which the direction finding units operate on a phase difference technique.

12. ) The system of claim 10 in which the display unit displays the seat number of the offending cellular telephone.

13. ) The system of claim 10 in which the direction finding units have comprise at least 2 antennas.

14. ) A method of locating nuisance cellular telephones consisting of the steps of:

a) installing at least three radio frequency receiving systems inside of a public building

b) monitor for signals with cellular telephone frequencies

c) calculating an arrival time difference to a source of such frequencies calculating the location of the source from arrival time differences of the at least three receiving systems.