Multi-antenna handheld wireless communication device

• US 20060071864A1
• Filed: 09/30/2004
• Published: 04/06/2006
• Est. Priority Date: 09/30/2004
• Status: Active Grant

• Current Assignee: Google Technology Holdings LLC (Alphabet Inc.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Faraone, Antonio, Richard, Miguel A.
• Granted Patent: US 7,102,577 B2
• Time in Patent Office: Days
• US Class Current: 343/702
• CPC Class Codes: H01Q 1/242 specially adapted for hand-held use
• CPC Class Codes: H01Q 1/243 with built-in antennas
• CPC Class Codes: H01Q 1/362 for broadside radiating helical antennas
• CPC Class Codes: H01Q 1/48 Earthing means; Earth screens; Counterpoises
• CPC Class Codes: H01Q 21/28 Combinations of substantially independent non-interacting antenna units or systems multiple beam H01Q25/00
• CPC Class Codes: H01Q 21/30 Combinations of separate antenna units operating in different wavebands and connected to a common feeder system
• CPC Class Codes: H01Q 9/16 with feed intermediate between the extremities of the antenna, e.g. centre-fed dipole H01Q9/44 takes precedence
• CPC Class Codes: H01Q 9/30 with feed to end of elongated active element, e.g. unipole H01Q9/44 takes precedence

Abstract

Antenna systems for handheld wireless communication devices (100) that comprise a first unbalanced feed antenna (112, 718, 802, 1204, 1812) and a second balanced feed antenna dipole antenna (202, 716, 804, 1202, 1802) that are located next to a ground structure (116, 810, 1210, 1824) for the handheld wireless communication devices are provided. The balanced feed dipole antenna and the unbalanced feed antenna exhibit disparate spatial-polarization patterns which are suitable for use with a MIMO transceiver, and the decorrelation of signals received by the two antennas is preserved due to a low level of coupling through the ground structure, which is due, in part, to differences in the symmetry properties of current patterns in the ground structure that are associated with the operation of the two antennas. The two antennas can also be used in a transceiver (629) that uses separate antennas to receive and transmit.

Claims

1. A handheld wireless communication device comprising:

an unbalanced feed antenna;

a ground structure disposed proximate said unbalanced feed antenna, said ground structure serving as a counterpoise for said unbalanced feed antenna; and

a balanced feed antenna disposed proximate said ground structure wherein said balanced feed antenna is coupled through electromagnetic interaction to said ground structure.

2. The handheld wireless communication device according to claim 1 wherein

said unbalanced feed antenna comprises a first terminal disposed proximate a transverse center of said ground structure;

and

said balanced feed antenna comprises a second feed terminal and a third feed terminal that are disposed proximate said transverse center of said ground structure.

3. The handheld wireless communication device according to claim 1 wherein

said unbalanced feed antenna comprises a first feed terminal disposed proximate a transverse center of said ground structure;

and

said balanced feed antenna comprises a second feed terminal and a third feed terminal which are disposed on opposite sides of said transverse center of said ground structure.

4. The handheld wireless communication device according to claim 1 wherein said ground structure comprises a ground plane of a printed circuit.

5. The handheld wireless communication device according to claim 4 wherein

said unbalanced feed antenna is attached to said printed circuit, and said balanced feed antenna is disposed on said printed circuit.

6. The handheld communication device according to claim 1 wherein:

said ground structure comprises a first end and a second end opposite said first end;

wherein, said unbalanced feed antenna is disposed proximate said first end, and

said balanced feed antenna is disposed proximate said second end.

7. The handheld communication device according to claim 1 wherein:

said balanced feed antenna comprises a dipole antenna; and

said unbalanced feed antenna comprises a monopole antenna.

8. The handheld communication device according to claim 1 wherein:

said balanced feed antenna comprises a dipole antenna; and

unbalanced feed antenna comprises a planar inverted “

F”

antenna.

9. The handheld communication device according to claim 1 further comprising:

a transmitter coupled to said unbalanced feed antenna; and

a receiver coupled to said balanced feed antenna.

10. The handheld communication device according to claim 1 further comprising:

a receiver coupled to said unbalanced feed antenna; and

a transmitter coupled to said balanced feed antenna.

11. The handheld communication device according to claim 1 further comprising:

a first demodulator coupled to said unbalanced feed antenna;

a second demodulator coupled to said balanced feed antenna;

a MIMO processor coupled to said first demodulator and said second demodulator.

12. The handheld communication device according to claim 1 further comprising:

a first modulator coupled to said unbalanced feed antenna;

a second modulator coupled to said balanced feed antenna;

a MIMO processor coupled to said first modulator and said second modulator.

13. A handheld wireless communication device comprising:

a ground structure;

a fist antenna that establishes a first current pattern in said ground structure that exhibits substantial bilateral antisymmetry about a longitudinal axis of said ground structure;

a second antenna disposed proximate said ground structure, wherein said second antenna establishes a second current pattern that does not exhibit substantial bilateral antisymmetry about said longitudinal axis of said ground structure.

14. The handheld wireless communication device according to claim 13 wherein:

said second current pattern exhibits substantial bilateral symmetry about said longitudinal axis of said ground structure.

15. The handheld wireless communication device according to claim 13 wherein:

said second antenna is centered on said longitudinal axis.

16. The handheld communication device according to claim 13 wherein:

said second antenna comprises an unbalanced feed antenna.

17. The handheld communication device according to claim 13 wherein:

said second antenna comprises a monopole antenna.

18. The handheld communication device according to claim 13 wherein:

said second antenna comprises a planar inverted “

F”

antenna.

19. A handheld wireless communication device comprising:

a circuit board comprising a first end, a second end, a longitudinal axis that extends between said first end and said second end, and a ground plane;

a dipole antenna supported on said circuit board, wherein said dipole antenna is arranged perpendicular to said longitudinal axis, and said dipole antennas is disposed in substantially non overlapping relation to said ground plane; and

an unbalanced feed antenna disposed proximate said circuit board, whereby said ground plane of said circuit board serves as a counterpoise to said unbalanced feed antenna.

20. The handheld wireless communication device according to claim 19 wherein:

said unbalanced feed antenna comprises a monopole antenna.

21. The handheld wireless communication device according to claim 19

wherein said unbalanced feed antenna comprises a planar inverted “

F”

antenna.

22. The handheld wireless communication device according to claim 19 wherein:

said dipole antenna is disposed proximate said first end of said circuit board; and

said unbalanced feed antenna is disposed proximate said second end of said circuit board, and proximate a transverse center of said circuit board.