Small double C-patch antenna contained in a standard PC card

• US 5,657,028 A
• Filed: 03/31/1995
• Issued: 08/12/1997
• Est. Priority Date: 03/31/1995
• Status: Expired due to Term

• Current Assignee: Nokia Technologies Oy (Nokia Corporation)
• Original Assignee: Nokia Mobile Phones OY (Nokia Corporation)
• Inventors: Sanad, Mohamed
• Primary Examiner(s): Hajec, Donald T.
• Assistant Examiner(s): Ho, Tan
• Application Number:
  US08/414,573
• Time in Patent Office: 865 Days
• Field of Search: 343/700 MS, 343/702, 343/846, 343/767, 343/770
• US Class Current: 343/700.0MS
• CPC Class Codes: H01Q 1/22 by structural association with other equipment or articles
• CPC Class Codes: H01Q 1/2208 associated with components used in interrogation type services, i.e. in systems for information exchange between an interrogator/reader and a tag/transponder, e.g. in Radio Frequency Identification [RFID] systems methods or arrangements for sensing record carriers, e.g. for reading patterns G06K7/00; record carrier for use with machines and with at least a part designed to carry digital markings G06K19/00
• CPC Class Codes: H01Q 9/0407 Substantially flat resonant element parallel to ground plane, e.g. patch antenna dipole H01Q9/285; monopole H01Q9/40

Abstract

A module (1'"'"') adapted for insertion into a data processor (2). The module includes an interface (40) for electrically coupling the module to the data processor, a modem (42) that is bidirectionally coupled to the interface, an RF energy transmitter (44) having an input coupled to an output of the modem, an RF energy receiver (46) having an output coupled to an input of the modem, and a partially shorted, dual C-patch antenna (20) that is electrically coupled to an output of the RF energy transmitter and to an input of the RF energy receiver. The partially shorted, dual C-patch antenna is comprised of a truncated ground plane (22), a layer of dielectric material (28) having a first surface overlying the ground plane and an opposing second surface, and an electrically conductive layer (30) overlying the second opposing surface of the dielectric layer. The electrically conductive layer forms a radiating patch and has a rectangularly shaped aperture having a length that extends along a first edge of the electrically conductive layer and a width that extends towards an oppositely disposed second edge. The length has a value that is equal to approximately 20% to approximately 35% of a length of the first edge. The antenna further includes electrically conductive vias or feedthroughs (24) for shorting the electrically conductive layer to the ground plane at a region adjacent to a third edge (20a) of the electrically conductive layer.

Claims

1. An antenna structure, comprising:

a ground plane;

a layer of dielectric material having a first surface overlying said ground plane and an opposing second surface;

an electrically conductive layer overlying said second opposing surface of said dielectric layer, said electrically conductive layer being in the shape of a parallelogram and having a first rectangularly shaped radiating aperture having a length that extends along a first edge of said electrically conductive layer and a width that extends towards an oppositely disposed second edge, said electrically conductive layer further having a second rectangularly shaped radiating aperature having a length that extends along said first edge of said electrically conductive layer and a width that extends towards said oppositely disposed second edge, said first and second radiating apertures having a zero potential plane disposed therebetween; and

means for coupling radio frequency energy into or out of said electrically conductive layer, said coupling means being located within said zero potential plane and further being located nearer to one of said radiating apertures than the other.

2. An antenna structure as set forth in claim 1 wherein a sum of lengths of each of said first and second apertures has a value that is equal to approximately 20% to approximately 35% of a length of said first edge.

3. An antenna structure as set forth in claim 1 wherein said width of each of said first and second apertures has a value that is equal to approximately 15% to approximately 40% less than a width of said electrically conductive layer.

4. An antenna structure as set forth in claim 1 wherein said coupling means is comprised of means for connecting a coaxial cable to said electrically conductive layer.

5. An antenna structure, comprising:

a ground plane;

a layer of dielectric material having a first surface overlying said ground plane and an opposing second surface;

an electrically conductive layer overlying said second opposing surface of said dielectric layer, said electrically conductive layer being in the shape of a parallelogram and having a rectangularly shaped radiating aperture having a length that extends along a first edge of said electrically conductive layer and a width that extends towards an oppositely disposed second edge, said length having a value that is equal to approximately 20% to approximately 35% of a length of said first edge;

means for shorting said electrically conductive layer to said ground plane at a region adjacent to a third edge of said electrically conductive layer; and

means for coupling radio frequency energy into or out of said electrically conductive layer, said coupling means being located between said radiating aperture and said third edge.

6. An antenna structure as set forth in claim 5, wherein said width of said aperture has a value that is equal to approximately 15% to approximately 40% less than a width of said electrically conductive layer, and wherein said aperture is located from said third edge at distance that is approximately equal to said length of said aperture.

7. An antenna structure as set forth in claim 5, wherein said shorting means is comprised of one of a continuous short circuit means and a plurality of electrically conductive feedthroughs that pass through said dielectric layer between said ground plane and said electrically conductive layer.

8. An antenna structure as set forth in claim 5, wherein said couplings means is comprised of means for connecting a coaxial cable to said electrically conductive layer at a point between said aperture and said third edge.

9. An antenna structure as set forth in claim 5, wherein said length of said first edge is less than approximately 8.5 cm, and wherein said third edge has a length that is less than approximately 5.5 cm.

10. An antenna structure as set forth in claim 5, wherein said length of said first edge is approximately equal to a length of said third edge, wherein said length of said first edge is equal to approximately 2.7 cm, wherein said length of said aperture is equal to approximately 0.7 cm, and wherein said width of said aperture is equal to approximately 2 cm.

11. An antenna structure as set forth in claim 5, wherein said ground plane is truncated, and has dimensions that are approximately equal to the dimensions of said electrically conductive layer.

12. A module adapted for insertion into a data processor, said module comprising:

an interface for electrically coupling said module to the data processor;

a modem that is bidirectionally coupled to said interface;

an RF energy transmitter having an input coupled to an output of said modem;

an RF energy receiver having an output coupled to an input of said modem; and

a shorted, dual C-patch antenna that is electrically coupled to an output of said RF energy transmitter and to an input of said RF energy receiver, said shorted, dual C-patch antenna comprising,

a ground plane;

a layer of dielectric material having a first surface overlaying said ground plane and an opposing second surface;

an electrically conductive layer overlying said second opposing surface of said dielectric layer, said electrically conductive layer being in the shape of a parallelogram and having a radiating aperture having a length that extends along a first edge of said electrically conductive layer and a width that extends towards an oppositely disposed second edge, said length having a value that is equal to approximately 20% to approximately 35% of a length of said first edge;

means for shorting said electrically conductive layer to said ground plane at a region adjacent to a third edge of said electrically conductive layer; and

means for coupling said electrically conductive layer to said output of said transmitter and to said input of said receiver, said coupling means being located between said radiating aperture and said third edge;

wherein said width of said aperture has a value that is equal to approximately 15% to approximately 40% less than a width of said electrically conductive layer, and wherein said aperture is located from said third edge at a distance that is approximately equal to said length of said aperture.

13. A module as set forth in claim 12, wherein said shorting means is comprised of a plurality of electrically conductive feedthroughs that pass through said dielectric layer between said ground plane and said electrically conductive layer.

14. A module as set forth in claim 12, wherein said shorting means is comprised of a length of electrically conductive material that extends from said ground plane to said electrically conductive layer.

15. A module as set forth in claim 12, wherein said coupling means is comprised of means for connecting a coaxial cable to said electrically conductive layer at a point between said aperture and said third edge.

16. A module as set forth in claim 12, wherein said length of said first edge is less than approximately 8.5 cm, and wherein said third edge has a length that is less than approximately 5.5 cm.

17. A module as set forth in claim 12, wherein said length of said first edge is approximately equal to a length of said third edge, wherein said length of said first edge is equal to approximately 2.7 cm, wherein said length of said aperture is equal to approximately 0.7 cm, and wherein said width of said aperture is equal to approximately 2 cm.

18. A module as set forth in claim 12, wherein said ground plane is truncated, and has dimensions that are approximately equal to the dimensions of said electrically conductive layer.

19. A module as set forth in claim 12, wherein said module has dimensions of approximately 8.5 cm×

5.4 cm by 0.5 cm.

20. A module as set forth in claim 12, wherein said shorted, dual C-patch antenna has a resonant frequency of approximately 900 MHz.