Balanced multi-band antenna system

• US 6,600,450 B1
• Filed: 03/05/2002
• Issued: 07/29/2003
• Est. Priority Date: 03/05/2002
• Status: Active Grant

• Current Assignee: Google Technology Holdings LLC (Alphabet Inc.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Phillips, James P., Efanov, Andrew A.
• Primary Examiner(s): NGUYEN, HOANG V
• Application Number:
  US10/091,666
• Time in Patent Office: 511 Days
• Field of Search: 343/702, 343/742, 343/867, 343/741, 343/866, 343/725, 343/726, 343/700.MS
• US Class Current: 343/726
• CPC Class Codes: H01Q 1/243 with built-in antennas
• 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 5/357 using a single feed point
• 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 9/26 with folded element or elements, the folded parts being spaced apart a small fraction of operating wavelength resonant loop antennas H01Q7/00
• CPC Class Codes: H01Q 9/285 Planar dipole H01Q9/065 takes precedence; patch antenna H01Q9/0407

Abstract

A balanced antenna system for a communication device includes a balanced transmission line electromagnetically coupled to a transceiver of the device. A symmetrical dipole antenna element is operable at a first frequency driven by the balanced transmission line. A symmetrical loop antenna shares portions of the dipole antenna element and is operable at a second frequency driven by the transmission line. Preferably, the antenna system is disposed within a flip portion of the device housing.

Claims

1. A balanced antenna system for a communication device having a transceiver disposed within a housing, the system comprising:

a balanced transmission line electromagnetically coupled to the transceiver;

a symmetrical bent dipole antenna element coupled to the balanced transmission line, the bent dipole antenna operable at a first frequency; and

a symmetrical loop antenna connected to the balanced transmission line, the loop antenna sharing portions of the bent dipole antenna element, the loop antenna operable at a second frequency.

2. The system of claim 1, wherein the bent dipole is coupled at contact points with symmetric delta-matched conductors connected to the transmission line, and the loop antenna is formed from the delta-matched conductors and the portion of the bent dipole element between the contact points.

3. The system of claim 2, further comprising a pair of conductive arms connected to the delta-match conductors near the contact points.

4. The system of claim 3, wherein the pair of conductive arms provide tuning for the loop antenna.

5. The system of claim 3, wherein the pair of conductive arms provide a resonance near the second operating frequency.

6. The system of claim 3, wherein the pair of conductive arms provide a resonance at a third operating frequency.

7. The system of claim 3, further comprising a second pair of conductive arms connected to the delta-match conductors near the contact points, the second pairs of conductive arms provide a resonance at a third operating frequency.

8. The system of claim 1, further comprising a movable flip portion connected through a hinge assembly to the housing, wherein the antenna system is disposed in the flip portion of the communication device.

9. The system of claim 8, wherein the transmission line is inductively coupled to the transceiver through the hinge assembly.

10. The system of claim 8, wherein the flip-portion has an open and a closed position, and wherein the housing contains at least one conductive plate disposed therein such that when the flip portion is in a closed position against the housing the conductive plates tune an antenna impedance for correct matching to the transmission line.

11. The system of claim 8, wherein the flip portion includes a window area exposed therethrough, and wherein the loop antenna is disposed in a symmetrical arrangement around the window.

12. A balanced hybrid loop-dipole antenna system for a communication device having a transceiver disposed within a housing and a flip portion coupled to the housing through a hinge assembly, the system comprising:

a balanced transmission line electromagnetically coupled to the transceiver;

a symmetrical dipole antenna element coupled at contact points with symmetric delta-matched conductors connected to the balanced transmission line, the dipole antenna operable at a first frequency; and

a symmetrical loop antenna connected to the balanced transmission line, the loop antenna formed from the delta-matched conductors and the portion of the dipole element between the contact points, the loop antenna operable at a second frequency.

13. The system of claim 12, further comprising a pair of conductive arms connected to the delta-match conductors near the contact points, the pair of conductive arms provide a resonance frequency at one of the second operating frequency or a third operating frequency.

14. The system of claim 12, wherein the antenna system is disposed in the flip portion of the communication device.

15. The system of claim 12, wherein the flip portion has an open and a closed position, and wherein the housing contains at least one conductive plate disposed therein such that when the flip portion is in a closed position against the housing the conductive plates tune an antenna impedance for correct matching to the transmission line.

16. The system of claim 12, wherein the flip portion includes a window area exposed therethrough, and wherein the loop antenna is disposed in a symmetrical arrangement around the window.

17. A balanced hybrid loop-dipole antenna system for a communication device having a transceiver disposed within a housing and a flip portion coupled to the housing through a hinge assembly, the system comprising:

a balanced transmission line electromagnetically coupled to the transceiver;

a symmetrical dipole antenna element coupled at contact points with symmetric delta-matched conductors connected to the balanced transmission line, the dipole antenna disposed in the flip portion of the communication device and being operable at a first frequency; and

a symmetrical loop antenna connected to the balanced transmission line, the loop antenna disposed in the flip portion of the communication device and formed from the delta-matched conductors and the portion of the dipole element between the contact points, the loop antenna being operable at a second frequency.

18. The system of claim 17, wherein the flip portion includes a window area exposed therethrough, and wherein the loop antenna is disposed in a symmetrical arrangement around the window.