Grounded antenna for a wireless communication device and method
View Patent ↗A wireless communication device includes an antenna for wireless communication with a remote interrogator. Several embodiments are disclosed to increase the options available to designers of wireless communication devices. In some embodiments, the antenna is a quarter wavelength long with one end of the antenna being grounded to provide desired impedance matching characteristics. The position of the ground plane relative to the antenna is also varied between embodiments. The connection from a wireless communication chip to the antenna is also varied between embodiments to provide alternate structures.
1. A wireless communication device, comprising:
a substrate;
a wireless communication chip positioned on said substrate;
a ground plane positioned on said substrate; and
an antenna electrically coupled to said wireless communication chip and electrically shorted at one end to said ground plane.
2. The wireless communication device of claim 1 , wherein said wireless communication chip is positioned on a first side of said substrate and said ground plane is positioned on an opposite side of said substrate.
3. The wireless communication device of claim 1 , wherein said wireless communication chip is electrically coupled to said ground plane.
4. The wireless communication device of claim 3 , wherein said wireless communication chip is directly coupled to said ground plane.
5. The wireless communication device of claim 3 , wherein said wireless communication chip is reactively coupled to said ground plane.
6. The wireless communication device of claim 1 , wherein said wireless communication chip is positioned along an axis substantially perpendicular to a primary axis of said antenna.
7. The wireless communication device of claim 1 , wherein said wireless communication chip is positioned along an axis substantially parallel to a primary axis of said antenna.
8. The wireless communication device of claim 1 , wherein said antenna and said ground plane are connected to an antenna grounding element.
9. The wireless communication device of claim 1 , wherein said ground plane and said antenna are positioned on one side of said substrate.
10. The wireless communication device of claim 1 , wherein said wireless communication chip is capacitively coupled to said antenna.
11. The wireless communication device of claim 10 , wherein said wireless communication chip is capacitively coupled to said antenna by a non-conductive adhesive being interposed between a feed line extending from said wireless communication chip and said antenna.
12. The wireless communication device of claim 10 , wherein said wireless communication chip is capacitively coupled to said antenna by at least one inter digital stub.
13. The wireless communication device of claim 1 , further comprising a second antenna operating at a second frequency distinct from a first antenna's operating frequency of said first antenna.
14. The wireless communication device of claim 13 , wherein said second antenna is a patch antenna.
15. The wireless communication device of claim 13 , wherein said first antenna acts as a feed line to couple capacitively said second antenna to said wireless communication chip.
16. The wireless communication device of claim 1 , wherein said antenna and said ground plane are cut from a unitary piece of conductive foil.
17. The wireless communication device of claim 1 , wherein said substrate comprises a plastic material.
18. A method of constructing a wireless communication device, comprising:
creating an ground plane/antenna component from a unitary piece of conductive foil;
creating a chip component comprising a feed line, a chip grounding line, and a wireless communication chip;
wrapping said ground plane/antenna component around a substrate such that an antenna portion of said ground plane/antenna component is positioned on a side opposite that where a ground plane portion of said ground plane/antenna component is positioned; and
wrapping said chip component around a side of said substrate such that the chip is grounded by the chip grounding line and coupled to said antenna by said feed line.
19. The method of claim 18 , further comprising adhering said ground plane/antenna component to said substrate.
20. The method of claim 18 , further comprising adhering said chip component to said substrate.