Antenna system and apparatus for radio-frequency wireless keyboard

• US 6,507,763 B1
• Filed: 08/25/2000
• Issued: 01/14/2003
• Est. Priority Date: 09/17/1997
• Status: Expired due to Term

• Current Assignee: Logitech Europe S A (Logitech International SA)
• Original Assignee: Logitech Europe S A (Logitech International SA)
• Inventors: Teodoridis, Viron, Lazzarotto, Sergio, Schneider, Gerhard A.
• Primary Examiner(s): PATEL, RAMESH B
• Application Number:
  US09/648,318
• Time in Patent Office: 872 Days
• Field of Search: 700/83-86, 700/85, 343/702, 343/703, 343/866, 400/479, 710/613, 710/3, 710/15, 710/18, 710/131, 341/22, 341/26, 341/32, 345/169, 345/168, 455/66, 455/90, 455/11.1, 455/151.2, 455/550, 455/557, 455/575
• US Class Current: 700/84
• CPC Class Codes: G06F 3/0231 Cordless keyboards
• CPC Class Codes: H01H 2207/048 Inductive or infrared coupling
• CPC Class Codes: H01Q 1/2258 used with computer equipment
• CPC Class Codes: H01Q 1/2266 disposed inside the computer
• CPC Class Codes: H01Q 1/243 with built-in antennas
• 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

Abstract

An antenna system for a radio frequency (“RF”) wireless keyboard includes a metallic plate as a part of the antenna system. The metallic plate is located within the wireless keyboard. A RF transmitter is coupled to the metallic plate and an antenna wire which form an the antenna loop. The antenna loop may also be directly integrated into the metallic plate by creating a cut-out space in the metallic plate. The antenna system may also include the metallic plate directly coupled with the RF transmitter so that the metallic plate is a whip or dipole antenna. The RF transmitter generates RF signals associated with particular keyswitches of the wireless keyboard. The antenna system transmits the generated RF signals to a RF receiver that resides separately from, and that communicates with, the wireless keyboard.

Claims

1. In a radio frequency keyboard, a radio frequency transmission system comprising:

a substantially rigid keyswitch backing member having a metallic portion configured to form at least a portion of an antenna; and

a radio frequency transmitter having at least one output, at least one output coupled to the metallic portion of the rigid plate member, the radio frequency transmitter for generating a radio frequency signal.

2. The radio frequency transmission system of claim 1, wherein the metallic portion of the substantially rigid keyswitch backing member comprises a metal film.

3. The radio frequency transmission system of claim 1, wherein the metallic portion of the substantially rigid keyswitch backing member comprises a metal trace.

4. The radio frequency transmission system of claim 1, wherein the metallic portion of the substantially rigid keyswitch backing member comprises a metal plate.

5. The radio frequency transmission system of claim 1, wherein the metallic portion of the substantially rigid keyswitch backing member comprises a metal grid.

6. The radio frequency transmission system of claim 1 further comprising:

at least one antenna connector coupled between at least one output of the transmitter

and the metallic portion of the substantially rigid keyswitch backing member.

7. The antenna connector of claim 6 wherein the antenna connector is formed from an element of a group consisting of:

a conductive wire,

a conductive trace, and

a conductive bar.

8. The radio frequency transmission system of claim 6 wherein at least one antenna connector has at least one turn.

9. the antenna connector of claim 6 wherein the antenna connector lies in a plane defined by the substantially rigid keyswitch backing member.

10. The antenna connector of claim 6 wherein the antenna connector lies outside of a plane defined by the substantially rigid keyswitch backing member.

11. The radio frequency transmission system of claim 6 wherein the antenna connector and metallic portion of the substantially rigid keyswitch backing member form a closed loop antenna.

12. The radio frequency transmission system of claim 1, wherein the radio frequency transmitter is configured to generate the radio frequency signal in response to a user input to the keyboard.

13. In a radio frequency keyboard, a radio frequency transmission system comprising:

a substantially rigid backing for use with a keyswitch pad having a nonmetalized portion and a metalized portion; and

a radio frequency transmitter having a first output and a second output, at least one output coupled to the metalized portion of the substantially rigid backing, the radio frequency transmitter for generating a radio frequency signal.

14. The radio frequency transmission system of claim 13 further comprising at least one antenna connector coupled between one output of the transmitter and the metalized portion of the substantially rigid backing.

15. The radio frequency transmission system of claim 14 wherein the antenna connector and metalized portion of the substantially rigid backing form a closed loop antenna.

16. The antenna connector of claim 14 wherein the antenna connector is formed from an element of a group consisting of:

a conductive wire,

a conductive trace, and

a conductive bar.

17. The radio frequency transmission system of claim 13 wherein the metalized portion of the substantially rigid backing includes one or more of a group consisting of:

a metal trace,

a metal film,

a metal plate, and

a metal grid.

18. The radio frequency transmission system of claim 13, wherein the radio frequency transmitter is configured to generate the radio frequency signal in response to a user input to the keyboard.

19. An antenna system for use with a radio frequency device, the antenna system comprising:

a substantially rigid member including;

a metallic portion and

a nonmetallic portion; and

an antenna connector coupled with the metallic portion, the metallic portion and the antenna wire forming a closed loop for coupling with the radio frequency device.

20. The antenna system of claim 19 wherein the closed loop is configured to function within a radio frequency keyboard.

21. The antenna system of claim 20, wherein the closed loop is configured to function in response to a user input to the keyboard.

22. The radio frequency antenna system of claim 19 wherein:

the metallic portion of the substantially rigid member includes one or more of a group consisting of;

a metal trace,

a metal film,

a metal plate, and

a metal grid.

23. The antenna connector of claim 19 wherein the antenna connector is formed from an element of a group consisting of:

a conductive wire,

a conductive trace, and

a conductive bar.