MULTI-FEED ANTENNA APPARATUS AND METHODS

• US 20130088404A1
• Filed: 10/07/2011
• Published: 04/11/2013
• Est. Priority Date: 10/07/2011
• Status: Active Grant

• Current Assignee: Pulse Finland Oy (Yageo Corporation)
• Original Assignee: Pulse Finland Oy (Yageo Corporation)
• Inventors: Ramachandran, Prasadh, Raappana, Ari, Annamaa, Petteri
• Granted Patent: US 9,123,990 B2
• Time in Patent Office: Days
• US Class Current: 343/853
• CPC Class Codes: H01Q 1/243 with built-in antennas
• CPC Class Codes: H01Q 13/10 Resonant slot antennas
• CPC Class Codes: H01Q 5/40 Imbricated or interleaved structures; Combined or electromagnetically coupled arrangements, e.g. comprising two or more non-connected fed radiating elements
• 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 space efficient multi-feed antenna apparatus, and methods for use in a radio frequency communications device. In one embodiment, the antenna assembly comprises three (3) separate radiator structures disposed on a common antenna carrier. Each of the three antenna radiators is connected to separate feed ports of a radio frequency front end. In one variant, the first and the third radiators comprise quarter-wavelength planar inverted-L antennas (PILA), while the second radiator comprises a half-wavelength grounded loop-type antenna disposed in between the first and the third radiators. The PILA radiators are characterized by radiation patterns having maximum radiation axes that are substantially perpendicular to the antenna plane. The loop radiator is characterized by radiation pattern having axis of maximum radiation that is parallel to the antenna plane. The above configuration of radiating patterns advantageously isolates the first radiator structure from the third radiator structure in at least one frequency band.

Claims

1. A multi-feed antenna apparatus, comprising:

a first antenna element operable in a first frequency region and comprising;

a first radiator; and

a first feed portion, the first feed portion configured to be coupled to a first feed port;

a second antenna element operable in at least a second frequency region and a third frequency region, the second antenna element comprising;

a second radiator;

a second feed portion configured to be coupled to a second feed port; and

a third feed portion configured to be coupled to a third feed port;

wherein;

the second frequency region comprises a first carrier frequency and the third frequency region comprises a second carrier frequency; and

the second and the third feed portions cooperate to;

(i) enable inter-carrier aggregation of the first carrier and the second carrier into a single band, and (ii) to obviate diplexer matching specific to said single band.

2. A triple-feed antenna apparatus, comprising:

a first antenna element operable in a lower frequency band and comprising a first feed portion configured to be coupled to a first feed port;

a second antenna element operable in a second frequency band and comprising a second feed portion configured to be coupled to a second feed port; and

a third antenna element operable in an upper frequency band and comprising a third feed portion configured to be coupled to a third feed port;

wherein;

the first and third antenna elements are each configured to form a radiation pattern disposed primarily in a first orientation; and

the second antenna element is configured to form a radiation pattern disposed primarily in a second orientation that is substantially orthogonal to the first.

3. The antenna apparatus of claim 2, further comprising a matching network comprised of:

a first circuit coupled between a radio-frequency (RF) front end of assembly host transceiver and said first feed port;

a second circuit coupled between said RF front end and said second feed port; and

a third circuit coupled between said RF front end and said third feed port.

4. The antenna apparatus of claim 3, wherein:

said first and said second circuits cooperate to reduce electromagnetic coupling between a radiating structure of the first antenna element and a radiating structure of the second antenna element; and

said third and said second circuits cooperate to reduce electromagnetic coupling between a radiating structure of said third antenna element and a radiating structure of said second antenna element.

5. The antenna apparatus of claim 2, wherein:

said first, second and third antenna elements are disposed on a common carrier, at least a portion of the carrier being configured substantially parallel to a ground plane;

the radiation pattern of the first and third antenna elements each comprise an axis of maximum radiation that is substantially perpendicular to said ground plane; and

the radiation pattern of the second antenna element comprises an axis of maximum radiation substantially parallel to said ground plane.

6. The antenna apparatus of claim 5, wherein the disposition of said axes of maximum radiation of the first, the second, and the third antenna elements enable electrical isolation of the first antenna element from said third antenna element.

7. The antenna apparatus of claim 5, wherein the disposition of said axes of maximum radiation of the first, the second, and the third antenna elements enable substantial electrical isolation between:

the first antenna element and said third antenna element;

the first antenna element and said second antenna element; and

the second antenna element and said third antenna element.

8. The antenna apparatus of claim 2, wherein the first antenna element and the third antenna element each comprise a quarter-wavelength planar inverted-L antenna (PILA);

and

said second antenna element comprises a half-wavelength loop antenna.

9. The antenna apparatus of claim 2, wherein the second antenna element further comprises a radiator branch configured to form a loop structure configured to effect a resonance, said resonance configured to expand said second frequency band;

and

said radiating branch and said loop structure are configured spaced yet parallel to a ground plane of the antenna apparatus.

10. The antenna apparatus of claim 2, further comprising a common carrier, said common carrier comprising a dielectric element having a plurality of surfaces, and wherein:

the first antenna element and the third antenna element are disposed at least partly on a first surface of said plurality of surfaces; and

the second antenna element is disposed at least partly on a second surface of said plurality of surfaces, said second surface being disposed substantially parallel to a ground plane of the antenna apparatus, and said first surface is disposed substantially perpendicular to said ground plane.

11. The antenna apparatus of claim 10, wherein:

said first antenna element is disposed proximate a first edge of said first surface; and

said third antenna element is disposed proximate a second end of said first surface, said first end being disposed opposite said second end.

12. The antenna apparatus of claim 11, wherein:

said first antenna element is disposed at least partly on a third surface of said plurality of surfaces, said third surface proximate said first end; and

said third antenna element is disposed at least partly on a fourth surface of said plurality of surfaces, said fourth surface proximate said second end.

13. A radio frequency communications device, comprising:

an electronics assembly comprising a ground plane and one or more feed ports; and

a multiband antenna apparatus, the antenna apparatus comprising;

a first antenna structure comprising a first radiating element and a first feed portion coupled to a first feed port;

a second antenna structure comprising a second radiating element and a second feed portion coupled to a second feed port;

a third antenna structure comprising an third radiating element and a third feed portion coupled to a third feed port; and

wherein;

the second antenna structure and second feed port are disposed substantially between said first and third antenna structures.

14. The radio frequency communications device of claim 13, wherein said antenna apparatus is disposed proximate a bottom end of the ground plane.

15. The radio frequency communications device of claim 13, wherein said first and third radiating elements have radiation patterns which are substantially orthogonal to a radiation pattern of the second radiating element.

16. The radio frequency communications device of claim 15, wherein said substantially orthogonal radiation patterns provide sufficient antenna isolation between each radiating element to enable operation of the device in at least three distinct radio frequency bands.

17. A method of tuning a multi-feed antenna having first, second and third radiating elements and associated first, second, and third feed ports and matching circuits, the method comprising:

tuning a reactance of at least one of the matching circuits so as to create a dual resonance response in the radiating element associated therewith.

18. The method of claim 17, wherein the tuning is accomplished via at least selection of one or more capacitance values within said at least one matching circuit.

19. The method of claim 17, wherein the first and the third radiating elements each comprise a planar inverted-L antenna (PILA)-type element, and the tuning a reactance of at least one matching circuit comprises tuning the reactance associated with the first and the third circuits so as to produce multiple frequency bands within the emissions of the first and the third elements.

20. A method of radiator isolation for use in a multi-feed antenna apparatus of a radio frequency device, the antenna comprising first, second, and third antenna radiating elements, and at least first, second, and third feed portions, the method comprising:

electrically coupling the first feed point to the first radiating element, said coupling configured to effect a first radiation pattern having maximum sensitivity along a first axis;

electrically coupling the second feed point to the second radiating element, said electric coupling configured to effect a second radiation pattern having maximum sensitivity along a second axis; and

electrically coupling the third feed portion to the third radiating element, said coupling configured to effect a third radiation pattern having maximum sensitivity along said first axis;

wherein;

said second axis is configured orthogonal to said first axis; and

said configurations cooperate to effect isolation of the first radiating element from the third radiating element.