Space efficient magnetic antenna method

• US 8,922,440 B2
• Filed: 07/12/2010
• Issued: 12/30/2014
• Est. Priority Date: 12/21/2004
• Status: Active Grant

• Current Assignee: GaN Corporation
• Original Assignee: Q-Track Corporation
• Inventors: Schantz, Hans Gregory, DePierre, Robert Edward, Fluhler, James David, Siwiak, Kazimierz, Wolenec, Glenn, Gabig, Jerome Sylvester, Barron, James Matthew
• Primary Examiner(s): Owens, Douglas W
• Assistant Examiner(s): KIM, JAE K
• Application Number:
  US12/834,821
• Publication Number:
  US 20100277387A1
• Time in Patent Office: 1,632 Days
• Field of Search: 343/718, 343/787, 343/788, 343/866, 343/867, 343/876, 343/893, 343/895, 343/900
• US Class Current: 343/718
• CPC Class Codes: G01S 5/14 Determining absolute distances from a plurality of spaced points of known location
• CPC Class Codes: H01Q 1/273 Adaptation for carrying or wearing by persons or animals
• CPC Class Codes: H01Q 1/276 for mounting on helmets
• CPC Class Codes: H01Q 21/24 Combinations of antenna units polarised in different directions for transmitting or receiving circularly and elliptically polarised waves or waves linearly polarised in any direction circularly polarised patch antennas H01Q9/0428; circularly polarised horns H01Q13/0241; cross-polarised horns H01Q13/0258; polarisation converters H01Q15/242; cross-polarised rear feeds H01Q19/136; crossed polarisation dual antenna H01Q25/001
• CPC Class Codes: H01Q 7/00 Loop antennas with a substantially uniform current distribution around the loop and having a directional radiation pattern in a plane perpendicular to the plane of the loop
• CPC Class Codes: H01Q 7/08 Ferrite rod or like elongated core

Abstract

A space efficient magnetic antenna is disclosed for use in tracking, positioning and other applications. In a preferred embodiment, a space efficient magnetic antenna system comprises a first magnetic antenna with a first null axis aligned within a predetermined plane and a second magnetic antenna having a second null axis aligned substantially orthogonal to a first null axis. A second magnetic antenna system lies in a minimal coupling orientation with respect to a first magnetic antenna system. Additionally, a first magnetic antenna may further comprise a plurality of interconnected magnetic antenna elements. A space efficient magnetic antenna system may include an RF module. In further embodiments, the antenna system may enclose a substantial majority of the device including the RF module; the RF module may be enclosed substantially or wholly within one or more antennas of the antenna system.

Claims

1. A method for providing an omnidirectional space efficient magnetic antenna system, said method comprising:

generating a first magnetic antenna having a first antenna null axis

generating a second magnetic antenna having a second antenna null axis;

aligning said second antenna null axis substantially orthogonal to said first antenna null axis; and

positioning said second magnetic antenna in a minimal coupling orientation with respect to said first magnetic antenna at a first center to center distance from said first magnetic antenna;

said minimal coupling orientation providing at least 10 dB decoupling between said first magnetic antenna and said second magnetic antenna compared with a configuration providing a maximum coupling achievable between said first magnetic antenna and said second magnetic antenna at said first center to center distance from said first magnetic antenna to said second magnetic antenna wherein said first antenna and said second magnetic antenna are together positioned while maintaining an orthogonal relationship;

said first magnetic antenna having a first length dimension corresponding to said first antenna null axis and said second magnetic antenna having a second length dimension corresponding to said second antenna null axis;

said first length dimension of said first magnetic antenna being not equal to said second length dimension of said second magnetic antenna;

said omnidirectional space efficient magnetic antenna system providing omnidirectional coverage using said first magnetic antenna in combination with said second magnetic antenna.

2. The method as recited in claim 1, wherein said step of generating said first magnetic antenna further includes the step of:

winding a coil of said first magnetic antenna around a loopstick axis;

wherein said coil comprises turns lying parallel to a plane, said plane at a substantial diagonal angle from said loopstick axis.

3. The method as recited in claim 1, further including an RF module having at least one characteristic physical dimension, wherein said first magnetic antenna has said first antenna null axis at a substantial diagonal angle from said at least one characteristic physical dimension;

wherein the at least one characteristic physical dimension is one of the group consisting of overall length, overall width, and overall height.

4. The method as recited in claim 1, further including the step of:

embedding said first magnetic antenna and said second magnetic antenna in clothing;

wherein the first antenna null axis of said first magnetic antenna is substantially perpendicular to the second antenna null axis of said second magnetic antenna, said first antenna null axis and said second antenna null axis lying substantially in a horizontal plane.

5. The method as recited in claim 1, further including an RF module and further including the step of:

said RF module alternately utilizing said first magnetic antenna and said second magnetic antenna.

6. The method as recited in claim 1, further including an RF module and further including the step of:

said RF module employing said second magnetic antenna in phase quadrature relative to said first magnetic antenna.

7. The method as recited in claim 1, further including the step of:

generating a third magnetic antenna with a third antenna null axis mutually orthogonal to said first antenna null axis and said second antenna null axis.

13. The method as recited in claim 3, wherein said first length dimension corresponding to said first antenna null axis is greater than a width of said first magnetic antenna;

and

said second length dimension corresponding to said second antenna null axis is less than a width of said second magnetic antenna.

14. The method as recited in claim 13, wherein said first length dimension corresponding to said first antenna null axis is equal to said width dimension of said second magnetic antenna.

8. A method for providing an omnidirectional space efficient magnetic antenna system including an RF module, said method comprising:

generating a first magnetic antenna having a first null axis aligned in accordance with a predetermined plane;

generating a second magnetic antenna having a second null axis;

aligning said second null axis substantially orthogonal to said first null axis;

positioning said second magnetic antenna in a minimal coupling orientation with respect to said first magnetic antenna at a first center to center distance from said first magnetic antenna;

said minimal coupling orientation providing at least 10 dB decoupling between said first magnetic antenna and said second magnetic antenna compared with a configuration providing a maximum coupling achievable between said first magnetic antenna and said second magnetic antenna at said first center to center distance from said first magnetic antenna to said second magnetic antenna wherein said first antenna and said second magnetic antenna are together positioned while maintaining an orthogonal relationship;

said first magnetic antenna has having a first length dimension corresponding to said first null axis and said second magnetic antenna having a second length dimension corresponding to said second null axis;

said first length dimension of said first magnetic antenna being not equal to said second length dimension of said second magnetic antenna;

said RF module capable of transmitting or receiving omnidirectionally using said first magnetic antenna in combination with said second magnetic antenna.

9. The method as recited in claim 8, further including the step of:

said RF module alternately utilizing said first magnetic antenna and said second magnetic antenna.

10. The method as recited in claim 8, and further including the step of:

said RF module utilizing said second magnetic antenna in phase quadrature relative to said first magnetic antenna.

11. The method as recited in claim 8, further including the step of:

generating a third magnetic antenna with a third null axis mutually orthogonal to said first null axis and said second null axis.

12. The method as recited in claim 8, wherein said first magnetic antenna further comprises a bar, said bar is characterized by a principal axis corresponding to the greatest dimension of the group consisting of overall length, overall width, and overall height of said bar, said principal axis is characterized by an orientation relative to said first null axis, and said orientation of said principal axis is not substantially co-parallel to said first null axis.

15. A method for providing an omnidirectional space efficient magnetic antenna system for an RF module, said method comprising:

generating a first magnetic antenna having a first null axis aligned in accordance with a predetermined plane;

generating a second magnetic antenna having a second null axis;

aligning said second null axis substantially orthogonal to said first null axis;

aligning said second null axis in accordance with said predetermined plane;

positioning said second magnetic antenna in a minimal coupling orientation with respect to said first magnetic antenna at a first center to center distance from said first magnetic antenna;

said minimal coupling orientation providing at least 10 dB decoupling between said first magnetic antenna and said second magnetic antenna compared with a configuration providing a maximum coupling achievable between said first magnetic antenna and said second magnetic antenna at said first center to center distance from said first magnetic antenna to said second magnetic antenna wherein said first antenna and said second magnetic antenna are together positioned while maintaining an orthogonal relationship;

positioning said RF module interposed directly between said first magnetic antenna and said second magnetic antenna within a package enclosure that encloses said first magnetic antenna and said second magnetic antenna and said RF module;

said RF module comprising active circuitry configured for transmitting or receiving omnidirectionally using said first magnetic antenna and said second magnetic antenna;

said first magnetic antenna having a first length dimension corresponding to said first null axis and said second magnetic antenna having a second length dimension corresponding to said second null axis;

said first length dimension of said first magnetic antenna being not equal to said second length dimension of said second magnetic antenna;

said omnidirectional near field magnetic antenna system providing omnidirectional coverage using said first magnetic antenna in combination with said second magnetic antenna.

16. The method as recited in claim 15, further including the step of:

said RF module alternately utilizing said first magnetic antenna and said second magnetic antenna on a same frequency.

17. The method as recited in claim 15, further including the step of:

said RF module employing said second magnetic antenna in phase quadrature relative to said first magnetic antenna.

18. The method as recited in claim 15, further including the step of:

generating a third magnetic antenna with a third null axis mutually orthogonal to said first null axis and said second null axis.