Methods and apparatus for transmitting power and data using the human body

• US 8,064,953 B2
• Filed: 01/20/2009
• Issued: 11/22/2011
• Est. Priority Date: 04/27/2000
• Status: Expired due to Fees

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Bathiche, Steven N., Vablais, William, Williams, Lyndsay
• Primary Examiner(s): Gelin; Jean
• Application Number:
  US12/356,477
• Publication Number:
  US 20090191824A1
• Time in Patent Office: 1,036 Days
• Field of Search: 381/312, 381/315, 381/322, 381/326, 381/151, 607/59, 607/60, 607/32, 455/95, 455/100, 455/41.2, 455/106, 455/556.1, 455/556.2, 455/557, 128/662.03, 736/29, 736/27
• US Class Current: 455/556.1
• CPC Class Codes: H04B 13/005 Transmission systems in which the medium consists of the human body
• CPC Class Codes: H04Q 9/04 Arrangements for synchronous operation

Abstract

Methods and apparatus for distributing power and data to devices coupled to the human body are described. The human body is used as a conductive medium, e.g., a bus, over which power and/or data is distributed. Power is distributed by coupling a power source to the human body via a first set of electrodes. One or more devices to be powered, e.g., peripheral devices, are also coupled to the human body via additional sets of electrodes. The devices may be, e.g., a speaker, display, watch, keyboard, etc. A pulsed DC signal or AC signal may be used as the power source. By using multiple power supply signals of differing frequencies, different devices can be selectively 15 powered. For example, a 100 Hz signal may be used to power a first device while a 150 Hz signal may be used to power a second device. Digital data and/or other information signals, e.g., audio signals, can be modulated on the power signal using frequency and/or amplitude modulation techniques. The power source and peripheral devices can interact to form a complete computer network where the body serves as the bus coupling the devices together. Devices can include optional batteries, one or more CPUs, transmit/receive circuitry, and/or input/output circuitry. In one particular exemplary network implementation the first device to be placed on the body operates as a master device, e.g., bus master, with one or more subsequently added devices working as slaves.

Claims

1. A system that facilitates reduction of wiring in connection with networking portable devices, comprising:

a plurality of devices that are electrically networked together via a human body, which serves as a transmission medium for at least a subset of the devices, a power signal having an information signal modulated on the power signal is transmitted between the subset of the devices through the human body, wherein one of the plurality of devices that receives the power signal includes a filter circuit that allows a signal frequency of the power signal to pass and rejects other frequencies and a demodulator that demodulates the power signal to produce the information signal.

2. The system of claim 1, wherein an audio signal is transmitted between at least some of the subset of the devices through the human body.

3. The system of claim 2, wherein one of the plurality of devices that receives the audio signal comprises a piezo electric speaker with leads coupled directly to the human body.

4. The system of claim 1, wherein a digital signal is transmitted between at least some of the subset of the devices through the human body.

5. The system of claim 1, wherein an analog signal is transmitted between at least some of the subset of the devices through the human body.

6. The system of claim 1, wherein at least one of the devices is a set of electronic earrings.

7. The system of claim 6, wherein the earrings measure functions of the human body.

8. The system of claim 1, wherein one of the plurality of devices comprises a kinetic converter.

9. The system of claim 1, wherein at least one of the plurality of devices comprises electrodes that are placed in physical contact with the human body.

10. The system of claim 1 , wherein at least one of the plurality of devices comprises footwear worn on the human body, the footwear comprising a kinetic converter configured to generate power sent through the power signal.

11. The system of claim 1, wherein a control signal indicates an oscillation frequency at which the power signal is transmitted between the subset of the devices.

12. The system of claim 1, wherein a pulse duration of the power signal is used to adjust an amount of power supplied to one or more of the plurality of devices.

13. The system of claim 1, wherein one of the plurality of devices acts as a power control master device.

14. The system of claim 13, wherein the plurality of devices other than the power control master device act as slave devices.

15. A portable computing device, comprising:

a pair of electrodes that electrically couples the device to skin of a living body, the pair of electrodes in physical contact with the skin of the living body;

an oscillator that outputs a transmitted information signal having a frequency determined by a frequency control input signal;

a modulator that modulates a power transmission signal to encode the transmitted information signal onto the power signal, the power transmission signal transmitted through the pair of electrodes;

a demodulator that demodulates a received signal to produce a received information signal, the received signal received through the pair of electrodes; and

a filter circuit that allows a signal frequency which supplies power to the portable device to pass and rejects other frequencies.

25. The portable computing device of claim 15, wherein the oscillator outputs the transmitted information signal as a square wave signal.

26. The portable computing device of claim 15, wherein the oscillator outputs the transmitted information signal as a sine wave signal.

27. The portable computing device of claim 15, wherein the information signal is modulated on the power signal using amplitude modulation of the power signal.

28. The portable computing device of claim 15, wherein the information signal comprises an analog signal encoding audio information.

29. The portable computing device of claim 28, wherein the audio information is converted directly into an acoustic audio signal by a piezo electric element of a speaker.

16. A method for transmitting signals, comprising:

generating a power supply signal with a first device;

encoding, by a modulator of the first device, an information signal on the power supply signal;

transmitting the power supply signal encoding the information signal through living tissue;

using a second device to receive the transmitted power supply signal encoding the information signal; and

demodulating, by a demodulator of the second device, the transmitted power supply signal encoding the information signal to produce the information signal.

17. The method of claim 16, wherein the second device is located within the living tissue.

18. The method of claim 17, wherein the first device is located outside the living tissue.

19. The method of claim 16, further comprising transmitting the signal upon request from the second device.

20. The method of claim 16, further comprising increasing amplitude of the signal to facilitate employment of the signal by the second device.

21. The method of claim 17, wherein the second device comprises a speaker located within the living tissue of an ear.

22. The method of claim 16, further comprising sending the signal as a power supply upon detection of low power status of the second device.

23. The method of claim 16, further comprising transmitting the signal across at least two living beings.

24. The method of claim 23, wherein the first device is located on a first living being and the second device if located on a second living being.

30. The method of claim 16, wherein the first device comprises a kinetic converter.

31. The method of claim 16, wherein the first device comprises footwear including a kinetic converter.

32. The method of claim 16, further comprising filtering, by a filter circuit of the second device, received signals such that a signal frequency of the power supply signal is allowed to pass and other frequencies are rejected.