US4012590A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Circuit arrangement for two-wire full duplex data transmission
Assignee: Siemens AG
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Filing: 1975-10-28
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Granted: 1977-03-15
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Expires: 1995-10-28
Abstract
Abstract A circuit arrangement for providing full duplex data communication over two wires is described. Each station connected to the two wires contains a transmitter and receiver. The receivers are connected across the two lines; a balancing resistor connects one of the two lines to each receiver. The balancing resistors are adapted so that transmitter operation in a given station does not interfere with reception. The receivers produce measuring signals for aiding in the reception of data from other stations. The measuring signals are equal in value to the difference between two currents; the first current is that which flows through a transmitter and the two lines in a given station, and the second current is that which flows through the transmitter and the balancing resistor in a given station.
Inventors
- 👤 Adolf Haass
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 20:50
CPC Classifications
H; H04; H04L; H04L5/00; H04L5/14; H04L5/1423
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
218 words
A circuit arrangement for two-wire, full duplex data transmission via two lines connecting at least two stations, wherein each said station comprises: receiver means connected to a first terminal, to a second terminal which is connected to one of said two lines and to a reference potential, transmitter means connected between a third terminal and said reference potential, balancing resistance means connected between said first and third terminals, said third terminal being connected to the other of said two lines and measuring means in said receiver means coupled to said first and second terminals so as to be responsive, respectively, to a first current flowing through said transmission means, said balancing resistance means, said first terminal and said receiver means to said reference potential and a second current flowing through said transmission means, said two lines, said second terminal and through said receiver means to said reference potential, said measuring means including means for generating a measuring signal for facilitating the reception of data, said measuring signal having a value indicating the difference between the values of said first and second currents if the algebraic signs of said first and second currents are the same and for indicating the sum of said first and second currents if the algebraic signs of said first and second currents are different.
Claim 2
Dependent Claim
218 words
A circuit arrangement for two-wire, full duplex data transmission via two lines connecting at least two stations, wherein each said station comprises: receiver means connected to a first terminal, to a second terminal which is connected to one of said two lines and to a reference potential, transmitter means connected between a third terminal and said reference potential, balancing resistance means connected between said first and third terminals, said third terminal being connected to the other of said two lines and measuring means in said receiver means coupled to said first and second terminals so as to be responsive, respectively, to a first current flowing through said transmission means, said balancing resistance means, said first terminal and said receiver means to said reference potential and a second current flowing through said transmission means, said two lines, said second terminal and through said receiver means to said reference potential, said measuring means including means for generating a measuring signal for facilitating the reception of data, said measuring signal having a value indicating the difference between the values of said first and second currents if the algebraic signs of said first and second currents are the same and for indicating the sum of said first and second currents if the algebraic signs of said first and second currents are different.
Claim 3
Dependent Claim
125 words
The circuit arrangement defined in claim 1 wherein said transmitter means comprises first and second voltage sources, wherein said first terminal comprises first and second connecting points, said first connecting point being connected to said balancing resistance means and said second connecting point being connected to said other line, said first voltage source being connected with a terminal of one polarity to said first connecting point and said second voltage source being connected with a terminal of the opposite polarity to said second connecting point, said first and second voltage sources being otherwise connected to said reference potential, and wherein said measuring means produces a measuring signal which is the sum of the values of the currents flowing through said first and second voltage sources.
Claim 4
Dependent Claim
29 words
The circuit arrangement defined in claim 2 wherein one of said voltage sources is a voltage inverter connected to the other of said voltage sources and said connecting point.
Claim 5
Dependent Claim
45 words
The circuit arrangement defined in claim 3 wherein said voltage inverter comprises an operational amplifier having a non-inverting input connected to said reference potential and an inverting input connected to the output of said other voltage source and to the output of said operational amplifier.
Claim 6
Dependent Claim
81 words
The circuit arrangement defined in claim 1 wherein said first terminal comprises first and second connecting points, said first connecting point being connected to said balancing resistance means and said second connecting point being connected to the other of said lines wherein said transmitter comprises a transformer and a data generator connected across the primary coil of said transformer, the secondary coil being connected between said first and second connecting points and having an intermediate tap connected to said reference potential.
Claim 7
Dependent Claim
62 words
The circuit arrangement defined in claim 1 wherein said measuring means comprises: an operational amplifier having a non-inverting input connected to said reference potential and an inverting input coupled to said first and second terminals, and impedance means connected between said inverting input and the output of said operational amplifier, the remainder of said receiver components being connected across said inpedance means.
References Cited (Backward Citations)
US3927257A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-03-14 | 1980-09-13 | 1981-03-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-03-14 | 1984-09-13 | 1985-03-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-03-14 | 1988-09-13 | 1989-03-15 | $7700.00 | Window Closed / Lapsed |