Dual-band glass-mounted antenna

• US 6,608,597 B1
• Filed: 09/24/2001
• Issued: 08/19/2003
• Est. Priority Date: 09/24/2001
• Status: Expired due to Term

• Current Assignee: Andrew Corporation (CommScope Holding Company, Inc.)
• Original Assignee: Allen Telecom Inc. (CommScope Holding Company, Inc.)
• Inventors: Warner, Michael E., Hrabak, Joseph, Hadzoglou, James
• Primary Examiner(s): Wimer, Michael C.
• Application Number:
  US09/961,653
• Time in Patent Office: 694 Days
• Field of Search: 343/713, 343/715, 343/860
• US Class Current: 343/713
• CPC Class Codes: H01Q 1/1285 with capacitive feeding through the windscreen
• CPC Class Codes: H01Q 5/321 within a radiating element or between connected radiating elements
• CPC Class Codes: H01Q 5/335 at the feed, e.g. for impedance matching

Abstract

A dual-band antenna assembly configured to be mounted on a dielectric substrate such as an automobile window glass. The dual-band antenna assembly is adapted to transmit and receive signals in two distinct frequency bands, particularly the cellular frequency band, 800-900 MHz and the PCS frequency band 1.8 GHz. The antenna assembly is further configured to couple signals in either frequency band through the dielectric so that signals originating on a first side of the dielectric substrate may be coupled to the antenna-radiating element located on the opposite side of the dielectric substrate and signals received by the antenna on the second side of the dielectric substrate may be coupled through the dielectric to a mobile telephone located on the first side of the substrate. Thus, signals originating from a mobile telephone unit located within a vehicle may be coupled to and transmitted by an antenna element on the outside of a vehicle, and signals received by the antenna maybe coupled to the mobile telephone inside the vehicle.

Claims

1. A dual-band antenna assembly for use in conjunction with a dielectric substrate, the assembly operable in two distinct frequency bands greater than 800 MHz, the dual band antenna assembly comprising:

a coupler assembly configured to be mounted on a first side of the dielectric substrate, the coupler assembly including a connector to which a transmission medium may be connected to carry electromagnetic signals to and from the coupler assembly;

a base housing assembly configured to be mounted on the second side of the dielectric substrate, the base housing assembly supporting a dual-band antenna radiating element;

a first coupling element associated with the coupler assembly and a second coupling element associated with the base housing whereby electromagnetic signals in the two distinct frequency bands maybe coupled between the coupling assembly and the base housing through the electric substrate; and

a conductive window frame associated with the base housing electrically insulated from the second coupling element and located as a counterpoise and a capacitively-coupled extension of the first coupling element between said first and second coupling elements when said coupler assembly and said base housing assembly are mounted on the substrate for coupling the two distinct frequency bands.

2. The dual-band antenna assembly of claim 1 further comprising an adhesive laminate for mounting the base housing assembly to the substrate, said conductive frame being embedded within said laminate.

3. The dual-band antenna assembly of claim 2 wherein said adhesive laminate comprises a first layer of pressure sensitive foam tape and a second layer of pressure sensitive foam tape, and said conductive frame comprises a thin aluminum foil layer disposed between said first and second layers of pressure sensitive foam tape.

4. The dual-band antenna assembly of claim 1 further comprising a matching circuit associated with the coupler assembly configured to match the impedance of the transmission medium connected to the coupler assembly with the impedance of the radiating element at both of the two distinct frequency bands.

5. The dual-band antenna assembly of claim 4 wherein said matching circuit comprises a three-dimensional air dielectric slotted microstrip transmission line circuit.

6. The dual-band antenna assembly of claim 5 wherein said matching circuit includes a first coupling surface oriented substantially parallel the first surface of the dielectric substrate when the coupler assembly is mounted thereon.

7. A through dielectric coupler adapted for use in conjunction with a dielectric material having a first surface and a second surface, the coupler comprising:

a first coupler assembly adapted for non-penetrating application to the first surface;

a second coupler assembly adapted for non-penetrating application to the second surface;

said first and second coupler assemblies each having a connection port for receiving a transmission medium whereby electromagnetic signals of two distinct frequency bands greater than 800 MHz and separated by a ratio of approximately 2;

1 may be carried to and transmitted from each coupler assembly;

each coupler assembly further comprising a coupling plate for coupling the electromagnetic signals through the dielectric material when said first and second coupler assemblies are mounted opposite one another across the dielectric;

the first coupler assembly including a matching circuit for matching the characteristic impedance of the transmission medium connected to the connection port associated with the first coupler assembly to the load impedance presented by the second coupler assembly at each of the distinct frequency bands; and

a conductive window frame associated with said second coupler assembly electrically isolated from the coupling plate of said second coupler assembly and positioned as a counterpoise and a capacitively-coupled extension of the first coupler assembly between coupling plates of each of the first and second coupler assemblies when the coupler assemblies are mounted on the dielectric material for coupling the two distinct frequency bands.

8. The through dielectric coupler of claim 7 wherein the connection port of the second coupler assembly is adapted to electrically connect to a dual-band antenna radiating element configured to operate in the two distinct frequency bands.

9. The through dielectric coupler of claim 7 further comprising an adhesive laminate for mounting the second coupler assembly to the second surface of the dielectric, said conductive window frame being embedded within the adhesive laminate.

10. The through dielectric coupler of claim 9 wherein said conductive window frame comprises a layer of aluminum foil.

11. The through dielectric coupler of claim 9 wherein said conductive window comprises an approximately 0.0035 inch thick aluminum foil square approximately 1.55 inches per side, having a 1 inch square cut out from the center thereof.

12. The through dielectric coupler of claim 9 wherein said conductive window comprises a conductive case and the matching circuit comprises a three-dimensional slotted microstrip transmission line circuit integrally formed with the coupling plate associated with the first coupler assembly mounted therein.

13. The through dielectric coupler of claim 12 wherein the first coupler assembly further comprises a dielectric cover having a two-sided adhesive thereon for mounting the first coupler assembly to the first surface of the dielectric material, said cover and said two-sided adhesive having a hole formed therein such that the coupling plate integrally formed with the matching circuit extends substantially parallel and adjacent to the first surface of the dielectric material.

14. The through dielectric coupler of claim 12 wherein said two distinct frequency bands comprise the cellular frequency band and the PCS frequency band.

15. A dual-band on-glass antenna assembly comprising a first coupler assembly adapted to be mounted on a first surface of a glass substrate, the first coupler assembly comprising a conductive shell having a coaxial cable connector mounted thereon, a three-dimensional slotted microstrip transmission line matching circuit mounted within the conductive shell, a first coupler plate integrally formed with the matching circuit, a dielectric cover enclosing the shell, and a foam adhesive tape affixed to the cover for mounting the first coupler assembly to the glass substrate;

a second coupler assembly adapted to be mounted on a separate surface of the glass substrate, the second coupler assembly comprising a base, a second coupling plate disposed on a bottom surface of the base, a two-sided adhesive laminate including a conductive window frame adhered to the base for mounting the second coupler to the second surface of the glass substrate in a position opposite the first coupler assembly, the conductive window frame being disposed between the first and second coupling plates, and an adjustable mount for pivotally supporting an antenna radiating element and electrically connecting the second coupling plate to the radiating element; and

a dual-band radiating element comprising a base for attaching the radiating element to the adjustable mount, a phasing coil, a first radiating member, a capacitive choke assembly, and a second radiating member.