Nuisance cell phone locator

• US 7,444,154 B2
• Filed: 04/15/2003
• Issued: 10/28/2008
• Est. Priority Date: 09/24/1999
• Status: Expired due to Fees

• Current Assignee: Kroll Family Trust
• Original Assignee: Kroll Family Trust
• Inventors: Kroll, Mark W.
• Primary Examiner(s): Smith; Creighton H
• Application Number:
  US10/414,733
• Publication Number:
  US 20040018845A1
• Time in Patent Office: 2,023 Days
• Field of Search: 455/456, 455/431, 455/67.1, 455/67.3, 455/279.1, 455/278.1, 455/296, 455/304
• 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) monitoring for signals with cellular telephone frequencies;

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

d) calculating the location of the source from the angles-of-origin, wherein the angle-of-origin is determined by phase differential-to-amplitude response.

2. The method of claim 1, wherein step d) includes a seat location for the source.

3. The method of claim 1, wherein the public building is a theater.

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

at least two direction finding units;

a controller operably connected to the at least two direction finding units; and

a display operably connected to the controller, wherein the controller calculates the location of the nuisance cellular telephone using phase differential-to-amplitude response.

5. The system of claim 4, wherein each of the at least two direction finding units comprises at least two antennas.

6. The system of claim 4, further comprising a memory, wherein the memory stores seat location information.

7. The system of claim 6, wherein the controller comprises the memory.

8. The system of claim 6, wherein the controller calculates a seat number for the source.

9. A method of locating nuisance cellular telephones comprising:

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

monitoring for signals with cellular telephone frequencies;

calculating an angle-of-origin to a source of such frequencies; and

calculating the location of the source from the angles-of-origin, wherein the angle-of-origin is determined by phase differential-to-amplitude response.

10. The method of claim 9, wherein calculating the location of the source includes calculating a seat location for the source.

11. The method of claim 9, wherein the public building is a theater.