Patent US4255812A successfully refreshed from Google Patents.
US4255812A
Expired / Lapsed
US
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Signal regenerating apparatus with DC compensation
Assignee: Wincor Nixdorf International GmbH
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Filing: 1979-06-18
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Granted: 1981-03-10
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Expires: 1999-06-18
Abstract
Abstract In known signal regenerating apparatus a high frequency signal is continuously applied to the secondary side and inductively coupled back to a resonant circuit on the primary side. The resultant oscillations in the resonant circuit are modulated by the incoming communication signals. The so-modulated signals are coupled back to the secondary side where they are demodulated. The demodulated signals are identical to the communication signals except for a DC component. A separate rectifier circuit, similar to the demodulator circuit is therefore provided for rectifying the high frequency signal. The rectified high frequency signal constitutes a DC voltage which, when combined with the demodulated signals, will remove the undesired DC component therefrom.
Inventors
- 👤 Joseph Huellwegen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 11:40
CPC Classifications
H; H04; H04B; H04B5/00; H04B5/20; H04B5/24; H04B5/26; H04B5/266; H04L; H04L25/00; H04L25/02; H04L25/0264; H04L25/0266; H04L25/0268
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
234 words
In a communication system having ungrounded lines for transmission of communication signals and signal regenerating apparatus having an ungrounded primary side connected to said transmission line for receiving said communication signals and a secondary side electrically isolated from but inductively coupled to said primary side for furnishing output signals corresponding to said communication signals, said regenerating apparatus comprising resonant circuit means on said primary side, modulation means connected to said resonant circuit means and said transmission line for modulating high frequency oscillations induced in said resonant circuit means in accordance with said communication signals thereby creating modulated high frequency signals across said resonant circuit means, said regenerating apparatus further comprising means connected to said secondary side for generating high frequency signals, means for inductively coupling said high frequency signals to said resonant circuit means thereby inducing said high frequency oscillations therein, and means connected on said secondary side for demodulating said modulated high frequency signals thereby creating demodulated signals corresponding to said communication signals but having an undesired DC component, the improvement comprising rectifier means connected to said high frequency signal generating means for rectifying said high frequency signals and furnishing a DC compensating signal corresponding thereto; and means connected to said rectifier means and said demodulating means for combining said demodulated signals and said DC compensating signal to remove said undesired DC component thereby creating said output signals corresponding to said communication signals.
Claim 2
Dependent Claim
234 words
In a communication system having ungrounded lines for transmission of communication signals and signal regenerating apparatus having an ungrounded primary side connected to said transmission line for receiving said communication signals and a secondary side electrically isolated from but inductively coupled to said primary side for furnishing output signals corresponding to said communication signals, said regenerating apparatus comprising resonant circuit means on said primary side, modulation means connected to said resonant circuit means and said transmission line for modulating high frequency oscillations induced in said resonant circuit means in accordance with said communication signals thereby creating modulated high frequency signals across said resonant circuit means, said regenerating apparatus further comprising means connected to said secondary side for generating high frequency signals, means for inductively coupling said high frequency signals to said resonant circuit means thereby inducing said high frequency oscillations therein, and means connected on said secondary side for demodulating said modulated high frequency signals thereby creating demodulated signals corresponding to said communication signals but having an undesired DC component, the improvement comprising rectifier means connected to said high frequency signal generating means for rectifying said high frequency signals and furnishing a DC compensating signal corresponding thereto; and means connected to said rectifier means and said demodulating means for combining said demodulated signals and said DC compensating signal to remove said undesired DC component thereby creating said output signals corresponding to said communication signals.
Claim 3
Dependent Claim
44 words
A communication system as set forth in claim 1, wherein said combining means comprises a difference amplifier having a first and second input terminal, and means for applying said demodulated signals and said DC compensating signal to said first and second input terminal, respectively.
Claim 4
Dependent Claim
89 words
A communication system as set forth in claim 1, wherein said inductive coupling means comprises a first coil; wherein said resonant circuit means comprises a second coil inductively coupled to said first coil and a capacitor connected in parallel with said second coil; wherein said demodulating means comprises a first transistor having an emitter-collector circuit interconnected between said first coil and said combining means; and wherein said rectifier means comprises a second transistor having an emitter-collector circuit interconnected between said high frequency signal generating means and said combining means.
Claim 5
Dependent Claim
22 words
A communication system as set forth in claim 1, wherein said resonant circuit means comprises an inductance having a minimal stray capacitance.
Claim 6
Dependent Claim
26 words
A communication system as set forth in claim 1, further comprising amplifier means connected between said high frequency signal generating means and said inductive coupling means.
Claim 7
Dependent Claim
55 words
A communication system as set forth in claim 5, wherein said resonant circuit means presents a predetermined equivalent resistance to the output of said amplifier means when tuned to a resonant frequency corresponding to the frequency of said high frequency signals; and wherein the internal resistance of said amplifier means corresponds to said equivalent resistance.
Claim 8
Dependent Claim
133 words
A communication system as set forth in claim 4, wherein said resonant circuit means comprises a second coil having a first and second end terminal and a center tap; wherein said stray capacitance includes a first and second stray capacitance respectively coupling said secondary side to said center tap said first end terminal; wherein said modulating means comprises a field effect transistor having a source-drain circuit connected from said first end terminal to said center tap of said second coil and a gate; and wherein said signal regenerating apparatus further comprises a first and second input terminal connected to said transmission line, first resistance means connected between said first input terminal and said gate of said field effect transistor, and second resistance means connected between said center tap and said second input terminal.
Claim 9
Dependent Claim
126 words
A communication system as set forth in claim 7, wherein a first noise signal is received at said first input terminal and a second noise signal in phase with said first noise signal is received at said second input terminal, whereby an amplified and inverted first noise signal is transmitted to said secondary side through said second stray capacitance and said second noise signal is transmitted to said secondary side through said first stray capacitance; and wherein said first resistance means has a resistance value exceeding the resistance value of said second resistance means so that said amplified and inverted second noise signal received on said secondary side has an amplitude substantially equal to the amplitude of said second noise signal received on said secondary side.
References Cited (Backward Citations)
DE2504785C3
Cited
US3997733A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-03-09 | 1984-09-08 | 1985-03-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-03-09 | 1988-09-08 | 1989-03-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-03-09 | 1992-09-08 | 1993-03-10 | $7700.00 | Window Closed / Lapsed |