US5581229A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Communication system for a power distribution line
Assignee: Landis and Gyr Technologies LLC
•
Filing: 1993-07-19
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Granted: 1996-12-03
•
Expires: 2013-07-19
Abstract
Abstract The invention provides a layered modulation data communication systems characterized by numerous, asynchronous data transmitters operating on a power line. Data is modulated onto relatively low frequency subcarriers. Subcarriers are used to modulate carriers centered on a common frequency. The subcarriers are frequency division multiplexed. Data is recovered by demodulating the subcarriers from the carriers and subsequently demodulating the data from the subcarriers.
Inventors
- 👤 Paul C. Hunt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 22:12
CPC Classifications
G; G01; G01R; G01R31/00; G01R31/44; H; H02; H02J; H02J13/00; H02J13/13; H02J13/1311; H02J13/1313; H02J13/18; H02J13/333; H04; H04B; H04B3/00; H04B3/54; H04B3/546; H04B2203/00; H04B2203/54; H04B2203/5404; H04B2203/5408; H04B2203/5416; H04B2203/5425; H04B2203/5429; H04B2203/5433; H04B2203/5441; H04B2203/5458; H04B2203/5462; H04B2203/5483; H05; H05B; H05B47/00; H05B47/10; H05B47/175; H05B47/185; Y; Y02; Y02E; Y02E60/00; Y04; Y04S; Y04S40/00; Y04S40/12; Y04S40/121
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
225 words
A power line distribution communications system for transmitting selected information on an electric power distribution line transmitting power at a selected power frequency, the power line distribution communications system comprising: a transmitter coupled to the electric power distribution line comprising: an information signal generator providing an information signal; first reference means for detecting a power frequency of an alternating current transmitted on the electric power distribution line; a first modulator connected to the information signal generator for taking the information signal as a modulating input for modulation of a subcarrier signal, the first modulator being operably connected to the first reference means such that the subcarrier signal has a frequency derived from and numerically referenced to the detected power frequency; and a second modulator taking the subcarrier signal as a modulating input for modulation of an output carrier signal, the output carrier signal having a frequency higher than the subcarrier signal; and a receiver coupled to the electric power distribution line comprising: second reference means for detecting the power frequency of the alternating current transmitted on the electric power distribution line and providing a reference signal indicative of the detected power frequency; means for demodulating the subcarrier signal from the output carrier signal; and means operably connected to the second reference means for demodulating the information signal from the subcarrier signal using the reference signal.
Claim 2
Dependent Claim
225 words
A power line distribution communications system for transmitting selected information on an electric power distribution line transmitting power at a selected power frequency, the power line distribution communications system comprising: a transmitter coupled to the electric power distribution line comprising: an information signal generator providing an information signal; first reference means for detecting a power frequency of an alternating current transmitted on the electric power distribution line; a first modulator connected to the information signal generator for taking the information signal as a modulating input for modulation of a subcarrier signal, the first modulator being operably connected to the first reference means such that the subcarrier signal has a frequency derived from and numerically referenced to the detected power frequency; and a second modulator taking the subcarrier signal as a modulating input for modulation of an output carrier signal, the output carrier signal having a frequency higher than the subcarrier signal; and a receiver coupled to the electric power distribution line comprising: second reference means for detecting the power frequency of the alternating current transmitted on the electric power distribution line and providing a reference signal indicative of the detected power frequency; means for demodulating the subcarrier signal from the output carrier signal; and means operably connected to the second reference means for demodulating the information signal from the subcarrier signal using the reference signal.
Claim 3
Dependent Claim
39 words
The power line distribution communications system of claim 1 wherein the first modulator is a frequency shift keying modulator and the subcarrier signal is modulated using frequency shift keying between an assigned mark frequency and an assigned space frequency.
Claim 4
Dependent Claim
54 words
The power line distribution communications system of claim 1 wherein the electric power distribution line provides power to a lamp at a selected location, and wherein the transmitter is located at the selected location, and wherein the information signal generator comprises a lamp sensor providing the information signal indicating operational status of the lamp.
Claim 5
Dependent Claim
52 words
The power line distribution communications system of claim 1 wherein the electric power distribution line provides power to a selected location, and wherein the transmitter is located at that selected location, and wherein the information signal generator comprises a power meter providing the information signal indicating power provided to the selected location.
Claim 6
Dependent Claim
19 words
The power line distribution communications system of claim 3 wherein the lamp is part of an airmen navigation aid.
Claim 7
Dependent Claim
17 words
The power line distribution communications system of claim 1 wherein the second modulator is a phase modulator.
Claim 8
Dependent Claim
19 words
The power line distribution communications system of claim 6 wherein the first modulator is a frequency shift keying modulator.
Claim 9
Dependent Claim
159 words
The power line distribution communications system of claim 7, and further including a plurality of transmitters coupled to the electric power distribution line, wherein each transmitter comprises: an information signal generator providing an information signal; first reference means for detecting a power frequency of an alternating current transmitted on the electric power distribution line; a frequency shift keying modulator connected to the information signal generator for taking the information signal as a modulating input for modulation of a subcarrier signal, the first reference means being operably connected to the first reference means such that the subcarrier signal has a frequency derived from and numerically referenced to the detected power frequency; and a second modulator taking the subcarrier signal as a modulating input for modulating of an output carrier signal, the output carrier signal having a frequency higher than the subcarrier signal; and wherein each transmitter is assigned an exclusive pair of mark and space frequencies for the subcarrier signal.
Claim 10
Dependent Claim
17 words
The power line distribution communications system of claim 1 wherein the first modulator is a phase modulator.
Claim 11
Dependent Claim
17 words
The power line distribution communications system of claim 1 wherein the first modulator is an amplitude modulator.
Claim 12
Dependent Claim
16 words
The power line distribution communications system of claim 1 wherein the second modulator an amplitude modulator.
Claim 13
Dependent Claim
39 words
The power line distribution communications system of claim 1 wherein the second modulator is operably connected to the first reference means and the output carrier signal has a frequency derived from and numerically referenced to the detected power frequency.
Claim 14
Dependent Claim
23 words
The power line distribution communications system of claim 12 wherein the frequency of the output carrier signal is equal to the power frequency.
Claim 15
Dependent Claim
20 words
The power line distribution communications system of claim 1 wherein the subcarrier signal has a bandwidth less than one hertz.
Claim 16
Independent Claim
257 words
A method of communicating information from a plurality of transmitters to a remote receiver station along a common electric power distribution line transmitting power at a selected power frequency, wherein a transmitter is provided at each of a plurality of spaced-apart transmitting locations, the method comprising the steps of: obtaining the information to be transmitted; generating an information signal at each transmitter location using the information to be transmitted; detecting a power frequency of an alternating current transmitted on the electric power distribution line at each transmitting location and providing an output signal as a function of the frequency of the alternating current; generating a subcarrier signal for each of the information signals using the output signal, the subcarrier signal having a frequency derived from and numerically referenced to the detected power frequency; modulating each subcarrier signal as a function of its associated information signal; modulating an output carrier signal with each subcarrier signal, the output carrier signal having a frequency higher than the subcarrier signal; transmitting the output carrier signals over the electric power distribution line; detecting the power frequency of the alternating current transmitted on the electric power distribution line at a receiving location and providing a reference signal indicative of the detected power frequency; recovering all carrier signals from the power distribution line; demodulating the subcarrier signals from the output carrier signals; demodulating the information signals from the subcarrier signals using the reference signal to provide associated output signals; and interpreting each of the output signals to obtain the information from each transmitting location.
Claim 17
Independent Claim
257 words
A method of communicating information from a plurality of transmitters to a remote receiver station along a common electric power distribution line transmitting power at a selected power frequency, wherein a transmitter is provided at each of a plurality of spaced-apart transmitting locations, the method comprising the steps of: obtaining the information to be transmitted; generating an information signal at each transmitter location using the information to be transmitted; detecting a power frequency of an alternating current transmitted on the electric power distribution line at each transmitting location and providing an output signal as a function of the frequency of the alternating current; generating a subcarrier signal for each of the information signals using the output signal, the subcarrier signal having a frequency derived from and numerically referenced to the detected power frequency; modulating each subcarrier signal as a function of its associated information signal; modulating an output carrier signal with each subcarrier signal, the output carrier signal having a frequency higher than the subcarrier signal; transmitting the output carrier signals over the electric power distribution line; detecting the power frequency of the alternating current transmitted on the electric power distribution line at a receiving location and providing a reference signal indicative of the detected power frequency; recovering all carrier signals from the power distribution line; demodulating the subcarrier signals from the output carrier signals; demodulating the information signals from the subcarrier signals using the reference signal to provide associated output signals; and interpreting each of the output signals to obtain the information from each transmitting location.
Claim 18
Dependent Claim
16 words
The method of claim 15 wherein all output carrier signals are centered on the same frequency.
Claim 19
Dependent Claim
22 words
The method of claim 15 wherein the step of modulating each subcarrier signal comprises modulating each subcarrier signal using frequency shift keying.
Claim 20
Dependent Claim
23 words
The method of claim 15 wherein the step of modulating an output carrier signal comprises modulating an output carrier signal using phase modulation.
Claim 21
Dependent Claim
227 words
A power line distribution communications system for transmitting selected information on an electric power distribution line transmitting power at a selected power frequency, the power line distribution communications system comprising: a transmitter coupled to the electric power distribution line comprising: an information signal generator providing an information signal; first reference means for detecting a power frequency of an alternating current transmitted on the electric power distribution line; a first modulator connected to the information signal generator for taking the information signal as a modulating input for modulation of a subcarrier signal; and a second modulator connected to the first modulator for taking the subcarrier signal as a modulating input for modulation of an output carrier signal, the second modulator being operably connected to the first reference means such that the output carrier signal has a frequency derived from and numerically referenced to the detected power frequency and a frequency higher than the subcarrier signal; and a receiver coupled to the electric power distribution line comprising: second reference means for detecting the power frequency of the alternating current on the electric power distribution line and providing a reference signal indicative of the detected power frequency; means for demodulating the subcarrier signal from the output carrier signal; and means operably connected to the second reference means for demodulating the information signal from the subcarrier signal using the reference signal.
Claim 22
Dependent Claim
227 words
A power line distribution communications system for transmitting selected information on an electric power distribution line transmitting power at a selected power frequency, the power line distribution communications system comprising: a transmitter coupled to the electric power distribution line comprising: an information signal generator providing an information signal; first reference means for detecting a power frequency of an alternating current transmitted on the electric power distribution line; a first modulator connected to the information signal generator for taking the information signal as a modulating input for modulation of a subcarrier signal; and a second modulator connected to the first modulator for taking the subcarrier signal as a modulating input for modulation of an output carrier signal, the second modulator being operably connected to the first reference means such that the output carrier signal has a frequency derived from and numerically referenced to the detected power frequency and a frequency higher than the subcarrier signal; and a receiver coupled to the electric power distribution line comprising: second reference means for detecting the power frequency of the alternating current on the electric power distribution line and providing a reference signal indicative of the detected power frequency; means for demodulating the subcarrier signal from the output carrier signal; and means operably connected to the second reference means for demodulating the information signal from the subcarrier signal using the reference signal.
Claim 23
Dependent Claim
23 words
The power line distribution communications system of claim 19 wherein the frequency of the output carrier signal is equal to the power frequency.
Claim 24
Dependent Claim
256 words
A power line distribution communications system for transmitting selected information on an electric power distribution line transmitting power at a selected power frequency, the power line distribution communications system comprising: a transmitter coupled to the electric power distribution line comprising: an information signal generator providing an information signal; first reference means for detecting a power frequency of an alternating current transmitted on the electric power distribution line; a first modulator connected to the information signal generator for taking the information signal as a modulating input for modulation of a subcarrier signal, the first modulator being operably connected to the first reference means such that the subcarrier signal having a bandwidth less than one hertz and a frequency derived from and numerically referenced to the detected power frequency; and a second modulator taking the subcarrier signal as a modulating input for modulation of an output carrier signal, the second modulator being operably connected to the first reference means such that the output carrier signal has a frequency derived from and numerically referenced to the detected power frequency and higher than the subcarrier signal; and a receiver coupled to the electric power distribution line comprising: second reference means for detecting the power frequency of the alternating current transmitted on the electric power distribution line and providing a reference signal indicative of the detected power frequency; means for demodulating the subcarrier signal from the output carrier signal; and means operably connected to the second reference means for demodulating the information signals from the subcarrier signal using the reference signal.
Claim 25
Dependent Claim
256 words
A power line distribution communications system for transmitting selected information on an electric power distribution line transmitting power at a selected power frequency, the power line distribution communications system comprising: a transmitter coupled to the electric power distribution line comprising: an information signal generator providing an information signal; first reference means for detecting a power frequency of an alternating current transmitted on the electric power distribution line; a first modulator connected to the information signal generator for taking the information signal as a modulating input for modulation of a subcarrier signal, the first modulator being operably connected to the first reference means such that the subcarrier signal having a bandwidth less than one hertz and a frequency derived from and numerically referenced to the detected power frequency; and a second modulator taking the subcarrier signal as a modulating input for modulation of an output carrier signal, the second modulator being operably connected to the first reference means such that the output carrier signal has a frequency derived from and numerically referenced to the detected power frequency and higher than the subcarrier signal; and a receiver coupled to the electric power distribution line comprising: second reference means for detecting the power frequency of the alternating current transmitted on the electric power distribution line and providing a reference signal indicative of the detected power frequency; means for demodulating the subcarrier signal from the output carrier signal; and means operably connected to the second reference means for demodulating the information signals from the subcarrier signal using the reference signal.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1999-12-03 | 2000-06-03 | 2000-12-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-12-03 | 2004-06-03 | 2004-12-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-12-03 | 2008-06-03 | 2008-12-03 | $7700.00 | Window Closed / Lapsed |