Method of and apparatus for using the digitizer sensor loop array of a computing device as an antenna for a radio frequency link to an external data source

• US 5,708,458 A
• Filed: 12/15/1994
• Issued: 01/13/1998
• Est. Priority Date: 12/15/1994
• Status: Expired due to Term

• Current Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Original Assignee: Compaq Computer Corporation (HP Inc.)
• Inventors: Vrbanac, Michael E.
• Primary Examiner(s): Powell, Mark R.
• Assistant Examiner(s): Kovalick, Vincent E.
• Application Number:
  US08/356,706
• Time in Patent Office: 1,125 Days
• Field of Search: 178/17 R, 178/18, 343/728, 343/732, 343/798, 343/824, 343/869, 343/891, 345/156, 345/157, 345/158, 345/168, 345/169, 345/170, 345/173, 345/175, 345/179, 345/180, 345/181, 345/182, 364/709.1, 375/7, 375/75, 375/83, 375/88, 375/89, 395/200.1
• US Class Current: 345/156
• CPC Class Codes: G06F 1/1626 with a single-body enclosure integrating a flat display, e.g. Personal Digital Assistants [PDAs]
• CPC Class Codes: G06F 1/1643 the display being associated to a digitizer, e.g. laptops that can be used as penpads details related to the relative motion of the display enclosure with respect to the body enclosure, e.g. to move between laptop and tablet PC configuration G06F1/1615
• CPC Class Codes: G06F 1/166 related to integrated arrangements for adjusting the position of the main body with respect to the supporting surface, e.g. legs for adjusting the tilt angle
• CPC Class Codes: G06F 1/1698 the I/O peripheral being a sending/receiving arrangement to establish a cordless communication link, e.g. radio or infrared link, integrated cellular phone details of antennas disposed inside a computer H01Q1/2266
• CPC Class Codes: G06F 2200/1632 Pen holder integrated in the computer
• CPC Class Codes: G06F 3/0219 Special purpose keyboards
• CPC Class Codes: G06F 3/0231 Cordless keyboards
• CPC Class Codes: G06F 3/041 Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
• CPC Class Codes: G06F 3/04162 for exchanging data with external devices, e.g. smart pens, via the digitiser sensing hardware
• CPC Class Codes: G06F 3/046 by electromagnetic means
• CPC Class Codes: H01H 2207/048 Inductive or infrared coupling

Abstract

A pen-enabled computer system in which the digitizer sensor loop array is employed as a radio frequency antenna for receiving signals from an external signal source such as a wireless keyboard or wireless local area network interface. This radio frequency datalink arrangement allows for greatly enhanced freedom of movement when using external system components, as well as reduced component count and weight.

Claims

1. A pen-enabled computer system for use with an external radio frequency serial data signal source including a radio frequency transmitter for transmitting a serial datastream radio frequency signal, the computer system comprising:

a digitizer pen;

a digitizer sensor loop array for cooperatively communicating with said digitizer pen and for receiving the serial datastream radio frequency signal, wherein the serial datastream radio frequency signal is provided by a source other than said digitizer pen; and

receiver circuitry electrically coupled to said digitizer sensor loop array, said receiver circuitry including means for retrieving the serial datastream radio frequency signal received by said digitizer sensor loop array and for providing a digital signal responsive to the serial datastream radio frequency signal.

2. The computer system of claim 1, wherein said digitizer pen provides a pen radio frequency signal, and further comprising:

digitizer control circuitry coupled to said digitizer sensor loop array, said digitizer control circuitry including means for differentiating said pen radio frequency signal from the serial datastream radio frequency signal and means for translating said pen radio frequency signal received by said digitizer sensor loop array into pen location data for use by said computer system.

3. The computer system of claim 2, wherein the serial datastream radio frequency signal is modulated at a frequency different than the transmission frequency of the pen radio frequency signal, and wherein said means for differentiating includes a first filter tuned to pass the serial datastream radio frequency signal and a second filter tuned to pass said pen radio frequency signal.

4. The computer system of claim 2, wherein said means for differentiating includes data decoding circuitry for separating said pen radio frequency signal from the serial datastream radio frequency signal.

5. The computer system of claim 1, in which said external radio frequency serial data signal is provided by an external keyboard.

6. The computer system of claim 5 in which the keyboard includes light emitting diodes (LEDs) and keyboard receiver circuitry for reception of LED radio frequency control signals, the computer system further comprising:

transmitter circuitry electrically coupled to said digitizer sensor loop array, said transmitter circuitry transmitting an LED control signal developed by said computer system for reception by the keyboard receiver circuitry for controlling LEDs on said external keyboard.

7. The computer system of claim 6, wherein said digitizer sensor loop array is integrated in a liquid crystal display unit.

8. The computer system of claim 1, in which said external radio frequency serial data signal is provided by a wireless computer networking interface.

9. The computer system of claim 1, wherein said means for retrieving includes frequency shift keying demodulation circuitry.

10. The computer system of claim 1, wherein said means for retrieving includes phase shift keying demodulation circuitry.

11. The computer system of claim 1, wherein said digitizer sensor loop array is integrated in a liquid crystal display unit.

12. A pen-enabled computer system with wireless connectivity, the pen-enabled computer system comprising:

an external keyboard transmitting a serial datastream radio frequency signal;

a pen-enabled computer, including;

a digitizer pen;

a digitizer sensor loop array for cooperatively communicating with said digitizer pen and for said serial datastream radio frequency signal from said external keyboard; and

receiver circuitry electrically coupled to said digitizer sensor loop array, said receiver circuitry including means for retrieving the serial datastream radio frequency signal received by said digitizer sensor loop array and for providing a digital signal responsive to the serial datastream radio frequency signal to the pen-enabled computer.

13. The computer system of claim 12, wherein said digitizer pen provides a pen radio frequency signal, said pen-enabled computer further comprising:

digitizer control circuitry coupled to said digitizer sensor loop array, said digitizer control circuitry including means for differentiating said pen radio frequency signal from the serial datastream radio frequency signal and means for translating said pen radio frequency signal received by said digitizer sensor loop array into pen location data for use by said computer system.

14. The computer system of claim 13, wherein the serial datastream radio frequency signal is modulated at a frequency different than the transmission frequency of the pen radio frequency signal, and wherein said means for differentiating includes a first filter tuned to pass the serial datastream radio frequency signal and a second filter tuned to pass said pen radio frequency signal.

15. The computer system of claim 13, wherein said means for differentiating includes data decoding circuitry for separating said pen radio frequency signal from the serial datastream radio frequency signal.

16. The computer system of claim 12, wherein said keyboard includes light emitting diodes (LEDs) and keyboard receiver circuitry for reception of LED radio frequency control signals, said pen-enabled computer further comprising:

transmitter circuitry electrically coupled to said digitizer sensor loop array, said transmitter circuitry transmitting an LED control signal developed by said computer system for reception by the keyboard receiver circuitry for controlling LEDs on said external keyboard.

17. The computer system of claim 16, wherein said digitizer sensor loop array is integrated in a liquid crystal display unit.

18. The computer system of claim 12, wherein said means for retrieving includes frequency shift keying demodulation circuitry.

19. The computer system of claim 12, wherein said means for retrieving includes phase shift keying demodulation circuitry.

20. The computer system of claim 12, wherein said digitizer sensor loop array is integrated in a liquid crystal display unit.

21. A system with wireless connectivity, the system comprising:

a wireless local area network interface transmitting a serial datastream radio frequency signal;

a pen-enabled computer, including;

a digitizer pen;

a digitizer sensor loop array for cooperatively communicating with said digitizer pen and for receiving said serial datastream radio frequency signal; and

receiver circuitry electrically coupled to said digitizer sensor loop array, said receiver circuitry including means for retrieving the serial datastream radio frequency signal received by said digitizer sensor loop array and for providing a digital signal responsive to the serial datastream radio frequency signal to the pen-enabled computer.

22. The system of claim 21, wherein said digitizer pen provides a pen radio frequency signal, said pen-enabled computer further comprising:

digitizer control circuitry coupled to said digitizer sensor loop array, said digitizer control circuitry including means for differentiating said pen radio frequency signal from the serial datastream radio frequency signal and means for translating said pen radio frequency signal received by said digitizer sensor loop array into pen location data for use by said computer system.

23. The system of claim 22, wherein the serial datastream radio frequency signal is modulated at a frequency different than the transmission frequency of the pen radio frequency signal, and wherein said means for differentiating includes a first filter tuned to pass the serial datastream radio frequency signal and a second filter tuned to pass said pen radio frequency signal.

24. The computer system of claim 22, wherein said means for differentiating includes data decoding circuitry for separating said pen radio frequency signal from the serial datastream radio frequency signal.

25. A method for establishing a radio frequency data link between a pen-enabled computer system and an external serial data signal source, wherein the external serial data source is other than a pen, comprising the steps of:

transmitting a serial datastream from the external serial data signal source;

utilizing the digitizer sensor loop array of the pen-enabled computer system as an antenna for reception of said serial datastream; and

demodulating said serial datastream for use as an input to said pen-enabled computer system.

26. The method of claim 25, in which said external serial data signal source is a wireless computer networking interface.

27. The method of claim 25, in which said external serial data signal source is an external keyboard.

28. The method of claim 27, further comprising the step of:

utilizing said digitizer sensor loop array as an antenna for transmitting an LED control signal developed by said computer system for controlling LED'"'"'s on said external keyboard.

29. A pen-enabled computer system for use with an external radio frequency serial data signal source including a radio frequency transmitter for transmitting a serial datastream radio frequency signal, the computer system comprising:

a digitizer pen;

a digitizer sensor loop array for cooperatively communicating with said digitizer pen and for receiving the serial datastream radio frequency signal, wherein the serial datastream radio frequency signal is provided by a source other than said digitizer pen; and

receiver circuitry electrically coupled to said digitizer sensor loop array, said receiver circuitry including demodulation circuitry for retrieving the serial datastream radio frequency signal received by said digitizer sensor loop array and for providing a digital signal responsive to the serial datastream radio frequency signal.

30. The computer system of claim 29, wherein said digitizer pen provides a pen radio frequency signal, and further comprising:

digitizer control circuitry coupled to said digitizer sensor loop array, said digitizer control circuitry including discrimination circuitry for distinguishing said pen radio frequency signal from the serial datastream radio frequency signal and digital circuitry for translating said pen radio frequency signal received by said digitizer sensor loop array into pen location data for use by said computer system.

31. The computer system of claim 29, further comprising a keyboard, wherein said external radio frequency serial data signal is provided by said keyboard.

32. The computer system of claim 31, wherein said keyboard comprises:

light emitting diodes (LEDs); and

keyboard receiver circuitry for receiving LED radio frequency control signals; and

the computer system further comprising;

radio frequency transmitter circuitry electrically coupled to said digitizer sensor loop array, said radio frequency transmitter circuitry utilizing said digitizer sensor loop array as an antenna in transmitting an LED control signal developed by said computer system for reception by said keyboard receiver circuitry.

33. The computer system of claim 29, wherein said digitizer sensor loop array is integrated in a liquid crystal display unit.

34. The computer system of claim 29, wherein said digitizer sensor loop array is integrated in an active matrix display.

35. The computer system of claim 29, wherein said digitizer sensor loop array is integrated in a field emission display.

36. A system with wireless connectivity, the system comprising:

a wireless local area network interface transmitting a serial datastream radio frequency signal;

a pen-enabled computer, comprising;

a digitizer pen;

a digitizer sensor loop array for cooperatively communicating with said digitizer pen and for receiving the serial datastream radio frequency signal; and

receiver circuitry electrically coupled to said digitizer sensor loop array, said receiver circuitry including demodulation circuitry for retrieving the serial datastream radio frequency signal received by said digitizer sensor loop array and for providing a digital signal responsive to the serial datastream radio frequency signal.

37. The system of claim 36, wherein said digitizer pen provides a pen radio frequency signal, and further comprising:

digitizer control circuitry coupled to said digitizer sensor loop array, said digitizer control circuitry including discrimination circuitry for distinguishing said pen radio frequency signal from the serial datastream radio frequency signal and digital circuitry for translating said pen radio frequency signal received by said digitizer sensor loop array into pen location data for use by said computer system.