CHASSIS-EXCITED ANTENNA APPARATUS AND METHODS

• US 20120206302A1
• Filed: 02/11/2011
• Published: 08/16/2012
• Est. Priority Date: 02/11/2011
• Status: Active Grant

• Current Assignee: Cantor Fitzgerald Securities (Cantor Fitzgerald, L.P.)
• Original Assignee: Cantor Fitzgerald Securities (Cantor Fitzgerald, L.P.)
• Inventors: Annamaa, Petteri, Ramachandran, Prasadh
• Granted Patent: US 8,648,752 B2
• Time in Patent Office: Days
• US Class Current: 343/702
• CPC Class Codes: H01Q 1/22 by structural association with other equipment or articles
• CPC Class Codes: H01Q 1/24 with receiving set
• CPC Class Codes: H01Q 1/243 with built-in antennas
• CPC Class Codes: H01Q 1/38 formed by a conductive layer on an insulating support patch antennas H01Q9/0407; microstrip dipole antennas H01Q9/065; microstrip slot antennas H01Q13/106; transmission line microstrip antennas H01Q13/206; manufacturing reflecting surfaces using insulating material for supporting the reflecting surface H01Q15/142
• CPC Class Codes: H01Q 1/42 Housings not intimately mechanically associated with radiating elements, e.g. radome
• CPC Class Codes: H01Q 1/50 Structural association of antennas with earthing switches, lead-in devices or lightning protectors
• CPC Class Codes: H01Q 13/10 Resonant slot antennas
• CPC Class Codes: H01Q 21/28 Combinations of substantially independent non-interacting antenna units or systems multiple beam H01Q25/00
• 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 9/42 with folded element, the folded parts being spaced apart a small fraction of the operating wavelength

Abstract

A chassis-excited antenna apparatus, and methods of tuning and utilizing the same. In one embodiment, a distributed loop antenna configuration is used within a handheld mobile device (e.g., cellular telephone). The antenna comprises two radiating elements: one configured to operate in a high-frequency band, and the other in a low-frequency band. The two antenna elements are disposed on different side surfaces of the metal chassis of the portable device; e.g., on the opposing sides of the device enclosure. Each antenna component comprises a radiator and an insulating cover. The radiator is coupled to a device feed via a feed conductor and a ground point. A portion of the feed conductor is disposed with the radiator to facilitate forming of the coupled loop resonator structure.

Claims

1. An antenna component for use in a portable communications device, the device comprising a ground, a feed port, and a metal structure having a plurality of sides, said component comprising:

a radiator element having a first dimension and a second dimension, a first and second surface, and configured to be disposed proximate to a first side of said plurality of sides;

a dielectric substrate having a third dimension and a fourth dimension, and configured to be disposed proximate the second surface; and

a feed conductor configured to couple to the radiator element at a feed point.

2. The antenna component of claim 1, wherein:

a normal projection of the dielectric substrate is equal or larger than a normal projection of the radiator element; and

the radiator element is electrically coupled to the ground at a ground point.

3. The antenna component of claim 2, wherein

at least a portion of the feed conductor is arranged along the first side substantially parallel to the first dimension;

and

the radiator element, the at least a portion of the feed conductor, and at least a portion of the first side form a coupled loop antenna operable in a first frequency band.

4. The antenna component of claim 3, further comprising a dielectric element disposed between the radiator element and the first side and configured to electrically isolate at least a portion of the first side from the radiator element.

5. The antenna component of claim 1, wherein the radiator element comprises a conductive structure comprising a first portion and a second portion, wherein the second portion is coupled to the feed point via a reactive circuit.

6. The antenna component of claim 5, further comprising a dielectric element disposed between the radiator element and the first side and configured to electrically isolate at least a portion of the first side from the radiator element.

7. The antenna component of claim 5, wherein the reactive circuit comprises a planar transmission line.

8. The antenna component of claim 5, wherein the second portion further comprises a second reactive circuit, configured to adjust electrical size of the radiator element.

9. The antenna component of claim 8, wherein the second reactive circuit comprises at least one of (i) an inductive element, and/or (ii) a capacitive element.

10. The antenna of claim 5, wherein

the radiator element comprises a dielectric substrate, and a conductive coating disposed thereon;

and

the conductive structure comprises the conductive coating.

11. The antenna component of claim 1, wherein

the metal structure comprises a sleeve like shape having at least a first cavity;

and

the first side comprises a metal support element disposed within the first cavity.

12. The antenna component of claim 1, wherein

at least a portion of the feed conductor is arranged along the first side substantially parallel to the first dimension;

and

the radiator element, the at least a portion of the feed conductor, and at least a portion of the first side form a coupled loop antenna operable in a first frequency band.

13. The antenna of claim 1, wherein the radiator element comprises a dielectric substrate, and a conductive coating disposed thereon.

14. The antenna of claim 1, wherein the radiator element comprises a flex circuit.

15. An antenna apparatus for use in a portable communications device comprising a metal structure having a plurality of sides and housing an electronics comprising a ground and at least one feed port, said antenna apparatus comprising:

a first antenna assembly configured to operate in a first frequency band, the first assembly comprising;

a first radiator element comprising a first ground point and a first feed point, and disposed along a first of the plurality of sides;

a first feed conductor coupled to the first feed point and to the at least one feed port; and

a first non-conductive cover disposed proximate the first radiator so as to substantially cover the first radiator; and

a second antenna assembly configured to operate in a second frequency band, the second assembly comprising;

a second radiator element comprising a second ground point and a second feed point, disposed along a second of the plurality of sides;

a second feed conductor coupled to the second feed point and to a feed port; and

a second non-conductive cover disposed proximate the second radiator so as to substantially cover the second radiator.

16. The antenna apparatus of claim 15, wherein:

the metal enclosure is electrically coupled to the ground, to the first ground point, and to the second ground point;

at least a portion of the first feed cable is disposed along the first side thereby forming a first coupled loop antenna structure between at least a portion of the enclosure, the first radiator element, and the at least a portion of the first feed cable; and

at least a portion of the second feed cable is disposed along the second side thereby forming a second coupled loop antenna structure between at least a portion of the enclosure, the second radiator element, and the at least a portion of the second feed cable.

17. The antenna apparatus of claim 16, wherein the first and second radiator elements are disposed substantially between the first and second covers, respectively, and the metal enclosure.

18. The antenna apparatus of claim 17, further comprising a dielectric element disposed between the radiator element and the first side and configured to electrically isolate at least a portion of the first side from the radiator element.

19. The antenna apparatus of claim 15, wherein the first and second radiator elements are disposed substantially between the first and second covers, respectively, and the metal enclosure.

20. The antenna of claim 15, wherein the first side surface is arranged substantially opposite from the second side surface.

21. The antenna of claim 15, wherein the first side is arranged adjacent the second side.

22. The antenna of claim 15, wherein the first frequency band comprises a frequency band between 700 and 960 MHz and the second frequency band comprised an upper frequency band.

23. The antenna of claim 22, wherein the upper frequency band comprises frequency band between 1710 and 2150 MHz.

24. The antenna of claim 22, wherein the upper frequency band comprises a global positioning system (GPS) frequency band.

25. The antenna of claim 15, wherein the feed port comprises the at least one feed port.

26. The antenna apparatus of claim 15, wherein

the metal structure comprises a sleeve like shape having a first cavity and a second cavity;

and

the first side comprises a first metal support element disposed within the first cavity and configured to receive the first radiator element; and

the second side comprises a second metal support element disposed within the second cavity and configured to receive the second radiator element.

27. An antenna component comprising:

a dielectric substrate having a plurality of surfaces;

a conductive coating disposed on at least one surface of the substrate, the conductive coating configured to form;

at least a portion of a ground plane, comprising a ground point;

a radiator structure comprising;

a feed;

a first portion;

a second portion;

a stripline coupled from said second portion to said feed point; and

a plurality of non conductive slots isolating substantially separating the strip line from the first portion; and

at least one ground clearance area disposed substantially within perimeter of the surface;

wherein the ground point is configured to couple the at least a portion of the ground plane to a ground of a host device; and

wherein the second portion is coupled to the first portion via a conductive element.

28. The antenna component of claim 27, wherein the second portion is further coupled to the first portion via a reactive circuit.

29. The antenna component of claim 28, wherein the reactive circuit comprises at least one of (i) an inductive element, and/or (ii) a capacitive element.

30. A mobile communications device, comprising:

a substantially metallic exterior housing comprising a plurality of sides;

an electronics assembly contained substantially therein and comprising a ground and at least one feed port;

a first antenna assembly configured to operate in a first frequency band, the first assembly comprising;

a first radiator element comprising a first ground point and a first feed point, and disposed along a first of the plurality of sides;

a first feed conductor coupled to the first feed point and to the at least one feed port; and

a first non-conductive cover disposed proximate the first radiator so as to substantially cover the first radiator; and

a second antenna assembly configured to operate in a second frequency band, the second assembly comprising;

a second radiator element comprising a second ground point and a second feed point, disposed along a second of the plurality of sides;

a second feed conductor coupled to the second feed point and to a feed port; and

a second non-conductive cover disposed proximate the second radiator so as to substantially cover the second radiator;

wherein;

the first ground point and the second ground point are electrically coupled to the metal housing;

a first coupled loop resonance structure is formed between at least a portion of the housing, the first radiator, and at least a portion of the first feed cable; and

a second coupled loop resonance structure is formed between at least a portion of the housing, the second radiator, and at least a portion of the second feed cable.