US4236244A
Expired / Lapsed
US
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Digital communications transmission system
Assignee: Siemens AG
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Filing: 1979-02-22
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Granted: 1980-11-25
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Expires: 1999-02-22
Abstract
Abstract A digital communications transmission system includes calling and called digital terminals which are interconnected with a two-wire line or a four-wire line by way of respective termination sets. Each terminal includes a transmitter, a receiver and a calling device. The transmission system is particularly characterized in that there is provided in the calling terminal a transmitter which transmits signals in a first frequency position and a receiver which receives signals in a second frequency position, while the called terminal includes a transmitter which transmits signals in the second frequency position and a receiver which receives signals in the first frequency position.
Inventors
- 👤 Herbert Strehl
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 21:01
CPC Classifications
H; H04; H04L; H04L5/00; H04L5/14; H04L5/143
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
158 words
A digital communications transmission system comprising: a transmission medium; a pair of termination sets connected to opposite ends of said transmission medium; and a calling terminal and a called terminal connected to respective ones of said termination sets, said calling terminal including a transmitter operable to transmit signals in a first frequency position, and a receiver operable to receive signals in a second frequency position, said called terminal including a transmitter operable to transmit signals in said second frequency position and a receiver operable to receive signals in said first frequency position. each of said transmitters comprising a digital input circuit for inputting digital signals, a frequency converter having an input, and an output connected to the respective termination set, a transmission transfer switch including an input connected to said digital input circuit, a first output connected to said input of said frequency converter, and a second output connected in common with said output of said frequency converter.
Claim 2
Dependent Claim
158 words
A digital communications transmission system comprising: a transmission medium; a pair of termination sets connected to opposite ends of said transmission medium; and a calling terminal and a called terminal connected to respective ones of said termination sets, said calling terminal including a transmitter operable to transmit signals in a first frequency position, and a receiver operable to receive signals in a second frequency position, said called terminal including a transmitter operable to transmit signals in said second frequency position and a receiver operable to receive signals in said first frequency position. each of said transmitters comprising a digital input circuit for inputting digital signals, a frequency converter having an input, and an output connected to the respective termination set, a transmission transfer switch including an input connected to said digital input circuit, a first output connected to said input of said frequency converter, and a second output connected in common with said output of said frequency converter.
Claim 3
Dependent Claim
17 words
The digital communications transmission system of claim 1, wherein said digital input circuit comprises: a data transmitter.
Claim 4
Dependent Claim
17 words
The digital communications transmission system of claim 1, wherein said digital input circuit comprises: an analog/digital converter.
Claim 5
Dependent Claim
70 words
The digital communications transmission system of claim 1, wherein each of said receivers comprises: a high-pass filter and a low-pass filter connected to said termination set; a frequency converter connected to said high-pass filter; a receiving transfer switch having a pair of inputs connected to said low-pass filter and to said frequency converter, respectively, and an output; and an output circuit connected to said output of said receiving transfer switch.
Claim 6
Dependent Claim
17 words
The digital communications transmission system of claim 4, wherein said frequency converters are constructed as code converters.
Claim 7
Dependent Claim
34 words
The digital communications transmission system of claim 4, further comprising: a ringing signal receiver in each of said terminals connected to said termination circuit and connected to operate said transmitting and receiving transfer switches.
Claim 8
Dependent Claim
14 words
The digital communications transmission system of claim 6, wherein each terminal is an exchange.
Claim 9
Dependent Claim
18 words
The digital communications transmission system of claim 7, wherein said transmitting and receiving transfer switches are identically set.
Claim 10
Dependent Claim
154 words
A digital communications transmission system comprising; a transmission medium; a pair of termination sets connected to opposite ends of said transmission medium; and a calling terminal and a called terminal connected to respective ones of said termination sets, said calling terminal including a transmitter operable to transmit signals in a first frequency position, and a receiver operable to receive signals in a second frequency position, and said called terminal including a transmitter operable to transmit signals in said second frequency position and a receiver operable to receive signals in said first frequency position, each of said receivers comprising a high-pass filter and a low-pass filter connected to said termination set, a frequency converter connected to said high-pass filter, a receiving transfer switch having a pair of inputs connected to said low-pass filter and to said frequency converter, respectively, and an output, and an output circuit connected to said output of said receiving transfer switch.
Claim 11
Dependent Claim
154 words
A digital communications transmission system comprising; a transmission medium; a pair of termination sets connected to opposite ends of said transmission medium; and a calling terminal and a called terminal connected to respective ones of said termination sets, said calling terminal including a transmitter operable to transmit signals in a first frequency position, and a receiver operable to receive signals in a second frequency position, and said called terminal including a transmitter operable to transmit signals in said second frequency position and a receiver operable to receive signals in said first frequency position, each of said receivers comprising a high-pass filter and a low-pass filter connected to said termination set, a frequency converter connected to said high-pass filter, a receiving transfer switch having a pair of inputs connected to said low-pass filter and to said frequency converter, respectively, and an output, and an output circuit connected to said output of said receiving transfer switch.
Claim 12
Dependent Claim
16 words
The digital communications transmission system of claim 9, wherein said output circuit comprises: a data receiver.
Claim 13
Dependent Claim
16 words
The digital communications transmission system of claim 9, wherein said output circuit comprises: a digital/analog converter.
Claim 14
Dependent Claim
165 words
A digital communications transmission system comprising: a transmission medium; a pair of termination sets connected to opposite ends of said transmission medium; and a calling terminal and a called terminal connected to respective ones of said termination sets, said calling terminal including a transmitter operable to transmit signals in a first frequency position, and a receiver operable to receive signals in a second frequency position, and said called terminal including a transmitter operable to transmit signals in said second frequency position and a receiver operable to receive signals in said first frequency position, each of said receivers comprising a diplexer including an input connected to said termination set, and a pair of outputs, a frequency converter connected to one of said outputs of said diplexer, a receiving transfer switch having a pair of inputs connected to the other of said outputs of said diplexer and said frequency converter, respectively, and an output, and an output circuit connected to said output of said receiving transfer switch.
Claim 15
Dependent Claim
165 words
A digital communications transmission system comprising: a transmission medium; a pair of termination sets connected to opposite ends of said transmission medium; and a calling terminal and a called terminal connected to respective ones of said termination sets, said calling terminal including a transmitter operable to transmit signals in a first frequency position, and a receiver operable to receive signals in a second frequency position, and said called terminal including a transmitter operable to transmit signals in said second frequency position and a receiver operable to receive signals in said first frequency position, each of said receivers comprising a diplexer including an input connected to said termination set, and a pair of outputs, a frequency converter connected to one of said outputs of said diplexer, a receiving transfer switch having a pair of inputs connected to the other of said outputs of said diplexer and said frequency converter, respectively, and an output, and an output circuit connected to said output of said receiving transfer switch.
Claim 16
Dependent Claim
16 words
The digital communications transmission system of claim 12, wherein said output circuit comprises: a data receiver.
Claim 17
Dependent Claim
16 words
The digital communications transmission system of claim 12, wherein said output circuit comprises: a digital/analog converter.
References Cited (Backward Citations)
US3655915A
Cited
DE2040401C3
Cited
US3937882A
Cited
US3993867A
Cited
US3936602A
Cited
US4041398A
Cited
DE2628852C2
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-11-25 | 1984-05-26 | 1984-11-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-11-25 | 1988-05-26 | 1988-11-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-11-25 | 1992-05-26 | 1992-11-25 | $7700.00 | Window Closed / Lapsed |