Patent USH678H successfully refreshed from Google Patents.
USH678H
Expired / Lapsed
US
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System for transmitting low frequency analog signals over AC power lines
Assignee: United States Department of Energy
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Filing: 1987-07-30
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Granted: 1989-09-05
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Expires: 2007-07-30
Abstract
Abstract A system for transmitting low frequency analog signals over AC power lines using FM modulation. A low frequency analog signal to be transmitted is first applied to a voltage-to-frequency converter where it is converted to a signal whose frequency varies in proportion to the analog signal amplitude. This signal is then used to modulate the carrier frequency of an FM transmitter coupled to an AC power line. The modulation signal frequency range in selected to be within the response band of the FM transmitter. The FM modulated carrier signal is received by an FM receiver coupled to the AC power line, demodulated and the demodulated signal frequency is converted by a frequency-to-voltage converter back to the form of the original low frequency analog input signal.
Inventors
- 👤 Steven P. Baker
- 👤 Robert L. Durall
- 👤 Howard D. Haynes
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 22:37
CPC Classifications
H; H04; H04B; H04B3/00; H04B3/54
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
222 words
A system for transmitting low frequency analog signals over an AC power line, comprising: a transmitting circuit means including a frequency modulating transmitter responsive to a modulation signal at an input thereof within a frequency response band of said transmitter for frequency modulating a carrier signal and coupling a resultjng modulated carrier signal to an AC power line and a voltage-to-frequency converter means responsive to said low frequency analog signal for continually converting said analog signal to a signal whose frequency varies in proportion to the amplitude of said analog signal over a frequency range corresponding to said frequency response band of said transmitter at an output thereof connected to the input of said frequency modulating transmitter; and a receiving circuit means including a frequency modulated signal receiver having an input coupled to said AC power line for receiving said modulated carrier signal and demodulating said carrier signal to reproduce said modulation signal at an output thereof and a frequency-to-voltage converter means connected to the output of said frequency modulated signal receiver for continually converting the frequency of said modulation signal at the output of said receiver to a signal having an amplitude proportional to said low frequency analog signal, so that said low frequency analog signal transmitted by said transmitting means is reproduced at the output of said receiving circuit means.
Claim 2
Independent Claim
222 words
A system for transmitting low frequency analog signals over an AC power line, comprising: a transmitting circuit means including a frequency modulating transmitter responsive to a modulation signal at an input thereof within a frequency response band of said transmitter for frequency modulating a carrier signal and coupling a resultjng modulated carrier signal to an AC power line and a voltage-to-frequency converter means responsive to said low frequency analog signal for continually converting said analog signal to a signal whose frequency varies in proportion to the amplitude of said analog signal over a frequency range corresponding to said frequency response band of said transmitter at an output thereof connected to the input of said frequency modulating transmitter; and a receiving circuit means including a frequency modulated signal receiver having an input coupled to said AC power line for receiving said modulated carrier signal and demodulating said carrier signal to reproduce said modulation signal at an output thereof and a frequency-to-voltage converter means connected to the output of said frequency modulated signal receiver for continually converting the frequency of said modulation signal at the output of said receiver to a signal having an amplitude proportional to said low frequency analog signal, so that said low frequency analog signal transmitted by said transmitting means is reproduced at the output of said receiving circuit means.
Claim 3
Dependent Claim
62 words
The system as set forth in claim 1 wherein said transmitter of said transmitting circuit means includes a frequency modulating transmitter having a modulation signal frequency response band of at least 1 to 10 kHz and wherein said receiver of said receiving circuit means includes a frequency modulated signal receiver having a frequency response band of at least 1 to 10 kHz.
Claim 4
Dependent Claim
16 words
The system as set forth in claim 2 wherein said carrier signal frequency is 200 kHz.
References Cited (Backward Citations)
US4300125A
Cited
US4538136A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-09-04 | 1993-03-06 | 1993-09-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-09-04 | 1997-03-06 | 1997-09-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-09-04 | 2001-03-06 | 2001-09-05 | $7700.00 | Window Closed / Lapsed |