COMMUNICATING OVER POWER DISTRIBUTION MEDIA

• US 20090299532A1
• Filed: 05/28/2009
• Published: 12/03/2009
• Est. Priority Date: 05/30/2008
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Intellon Corporation (Qualcomm, Inc.)
• Inventors: Zyren, James
• Granted Patent: US 8,258,649 B2
• Time in Patent Office: Days
• US Class Current: 700/276
• CPC Class Codes: H04B 2203/5433 Remote metering
• CPC Class Codes: H04B 2203/5458 Monitor sensor; Alarm systems
• CPC Class Codes: H04B 2203/547 via DC power distribution
• CPC Class Codes: H04B 3/546 Combination of signalling, telemetering, protection circuits for remote indication of supply or distribution network condition H02J13/00
• CPC Class Codes: H04B 3/56 Circuits for coupling, blocking, or by-passing of signals
• CPC Class Codes: H04L 27/2601 Multicarrier modulation systems

Abstract

A system includes a first communication module to be coupled to a first transmission medium for distributing power using a voltage waveform having a first amplitude; and a second communication module to be coupled to a second transmission medium for distributing power using a voltage waveform having a second amplitude different from the first amplitude, the second transmission medium being coupled to the first transmission medium. Each of the first and second communication modules is configured to use signals that propagate between the first and second transmission media.

Claims

1. A system, comprising:

a first communication module to be coupled to a first transmission medium for distributing power using a voltage waveform having a first amplitude; and

a second communication module to be coupled to a second transmission medium for distributing power using a voltage waveform having a second amplitude different from the first amplitude, the second transmission medium being coupled to the first transmission medium;

wherein each of the first and second communication modules is configured to use signals that propagate between the first and second transmission media.

2. The system of claim 1, wherein the second transmission medium is coupled to the first transmission medium by a transformer.

3. The system of claim 1, wherein the first transmission medium comprises at least a first length of wire, and the second transmission medium comprises at least a second length of wire.

4. The system of claim 3, wherein the second transmission medium is coupled to the first transmission medium by at least a portion of the first length of wire being distributed in proximity to at least a portion of the second length of wire.

5. The system of claim 1, wherein the second communication module is coupled to a thermostat and is configured to use signals to control the thermostat.

6. The system of claim 1, wherein the first communication module is coupled to a power line.

7. The system of claim 6, wherein the first communication module comprises a smart meter coupled to a Smart Power Grid.

8. The system of claim 1, wherein the first communication module is configured to operate in a bandwidth, wherein at least a portion of the bandwidth is above about 15 MHz.

9. The system of claim 1, wherein the first communication module is configured to use Orthogonal Frequency Division Multiplexing (OFDM).

10. The system of claim 1, wherein the first communication module is configured to use Orthogonal Frequency Division Multiplexing (OFDM) and binary frequency shift keying (BFSK) modulation.

11. The system of claim 1, wherein the second communication module is configured to use Orthogonal Frequency Division Multiplexing (OFDM).

12. The system of claim 1, wherein the second communication module is configured to use binary frequency shift keying (BFSK) modulation.

13. The system of claim 1, wherein the second communication module is configured to support data rates that are less than about 200 kbps.

14. The system of claim 1, wherein the first transmission medium comprises an Alternating Current (AC) domestic power distribution medium.

15. The system of claim 1, wherein the second transmission medium comprises a Heating, Ventilation, and Air Conditioning (HVAC) power distribution medium.

16. The system of claim 1, wherein the first amplitude is in the range of about 100-240 Volts rms.

17. The system of claim 16, wherein the second amplitude is about 24 Volts rms.

18. The system of claim 1, wherein the first and second voltage waveforms have a frequency in the range of about 50-60 Hz.

19. A method, comprising:

configuring a first communication module coupled to a Heating, Ventilation, and Air Conditioning (HVAC) power distribution medium to use signals that propagate between an Alternating Current (AC) domestic power distribution medium and the HVAC power distribution medium.

20. The method of claim 19, further comprising configuring a modulation scheme of a second communication module coupled to the AC domestic power distribution medium and configured to provide signals used by the first communication module.

21. The method of claim 20, wherein configuring the modulation scheme of the second communication module comprises selecting at least one pair of subcarrier frequencies for Frequency Shift Keying (FSK) modulation from a plurality of subcarrier frequencies used for Orthogonal Frequency Division (OFDM) modulation.

22. The method of claim 21, wherein selecting at least one pair of subcarrier frequencies comprises selecting a plurality of pairs of subcarrier frequencies.

23. The method of claim 22, further comprising transmitting a given signal from the second communication module using FSK modulation on multiple pairs of subcarriers having the selected subcarrier frequencies.

24. The method of claim 23, wherein the multiple pairs of subcarrier frequencies are separated from each other by a minimum number of intervening frequencies of subcarriers that are not used to transmit signals.

25. The method of claim 23, further comprising spreading the pairs of subcarrier frequencies from each other over the plurality of subcarrier frequencies used for OFDM modulation to compensate for frequency selective fading on the power distribution media.

26. The method of claim 25, wherein configuring the first communication module comprises selecting one of the pairs of subcarriers on which the given signal is received based on a signal quality parameter.

27. The method of claim 26, wherein the signal quality parameter comprises signal-to-noise ratio.

28. The method of claim 26, further comprising using the selected pair of subcarriers to transmit signals from the first communication module using FSK modulation.

29. The method of claim 21, wherein at least some of the selected pairs of subcarrier frequencies are adjacent frequencies separated by a frequency that is an inverse of a symbol time containing a whole number of periods of the sinusoidal waveform of each of multiple mutually orthogonal subcarriers.

30. The method of claim 29, wherein the symbol time is used for generating symbols within signals sent between the second communication module and the first communication module.

31. The method of claim 30, wherein the signals sent between the second communication module and the first communication module use FSK modulation.

32. The method of claim 21, wherein a modulation index for at least some of the selected pairs of subcarrier frequencies is on the order of one.

33. The method of claim 32, wherein a modulation index for at least some of the selected pairs of subcarrier frequencies is between about 0.6 and about 1.5.

34. The method of claim 33, wherein a modulation index for at least some of the selected pairs of subcarrier frequencies is approximately equal to one.

35. The method of claim 20, further comprising configuring a third communication module coupled to the AC domestic power distribution medium to use signals that propagate from the first communication module.

36. The method of claim 35, wherein configuring the modulation scheme of the second communication module comprises using Frequency Shift Keying (FSK) modulation for communication with the first communication module and using Orthogonal Frequency Division (OFDM) modulation for communication with the third communication module.

37. The method of claim 20, further comprising configuring a third communication module coupled to the HVAC power distribution medium to use signals that propagate between the AC domestic power distribution medium and the HVAC power distribution medium.

38. The method of claim 37, further comprising communicating in parallel between the first and second communication modules and between the first and third communication modules.

39. The method of claim 38, wherein configuring the modulation scheme of the second communication module comprises using a first pair of subcarrier frequencies for Frequency Shift Keying (FSK) modulation for communication with the first communication module and using a different second pair of subcarrier frequencies for Frequency Shift Keying (FSK) modulation for communication with the third communication module.

40. The method of claim 20, wherein configuring the modulation scheme of the second communication module comprises using Frequency Shift Keying (FSK) modulation for communication with the first communication module and using Orthogonal Frequency Division (OFDM) modulation for communication over a distribution cable from an AC domestic power grid.

41. A method, comprising:

communicating with a Heating, Ventilation, and Air Conditioning (HVAC) device coupled to lower voltage power distribution wiring in a premises by coupling signals to higher voltage power distribution wiring in the premises without detecting the signals before coupling the signals between the higher voltage power distribution wiring and the lower voltage power distribution wiring.

42. The method of claim 41, wherein the HVAC device comprises a thermostat.

43. An apparatus, comprising:

a communication module coupled to a Heating, Ventilation, and Air Conditioning (HVAC) power distribution medium configured to use signals that propagate between an Alternating Current (AC) domestic power distribution medium and the HVAC power distribution medium.