EP0522244A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Method and apparatus for transmitting signals on a transmission line
Assignee: Fuji Electric Co Ltd
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Filing: 1992-04-16
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Granted: —
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Expires: 2012-04-16
Abstract
Abstract The present invention provides a method and apparatus for transmitting signals on a transmission line, the transmission line having a DC current flowing therethrough and having a plurality of terminals connected thereto in a multidrop fashion. Each of the terminals is capable of drawing a portion of the DC current. A signal is transmitted on the transmission line by varying the portions of the DC current drawn by the terminals. When the signal is not being transmitted the total amount of the DC current drawn by the terminals from the transmission line is maintained at a value smaller than an average amount of the DC current drawn by the terminals from the transmission line when the signal is being transmitted. <IMAGE>
Inventors
- 👤 Fumihiko c/o Fuji Electric Co. Ltd. Takezoe
- 👤 Hironori c/o Fuji Electric Co. Ltd. Mine
- 👤 Kenji c/o Fuji Electric Co. Ltd. Asanuma
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-25 05:11
CPC Classifications
H; H04; H04L; H04L12/00; H04L12/28; H04L12/40; H04L12/40006; H04L12/40039; H04B; H04B3/00; H04B3/54; H04B3/548; H04L25/00; H04L25/02; H04B2203/00; H04B2203/54; H04B2203/5462; H04B2203/547
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
125 words
A method of transmitting signals on a transmission line, the transmission line having a DC current flowing therethrough and having a plurality of terminals connected thereto in a multidrop fashion, each of the terminals being connected to the transmission line to draw a portion of the DC current during transmission and non-transmission of a signal, comprising the steps of: maintaining a total amount of the DC current drawn from the transmission line by the terminals during non-transmission of the signal at a value smaller than an average amount of the DC current drawn from the transmission line by the terminals during transmission of the signal; and varying the portions of the DC current drawn by the terminals to transmit the signal on the transmission line.
Claim 2
Dependent Claim
37 words
The method of claim 1, further including the steps of: receiving a signal on the transmission line; and digitizing said received signal in accordance with a threshold level equal to an average value of the received signal.
Claim 3
Dependent Claim
120 words
The method of claim 1, wherein the step of varying the portions of the DC current drawn by the terminals includes the steps of: gradually increasing the amount of the DC current drawn from the transmission line from the value of the total amount of the DC current drawn during non-transmission of the signal to the average amount of the DC current drawn during transmission of the signal; and upon completion of transmission of the signal, gradually decreasing the amount of the DC current drawn from the transmission line from the average amount of the DC current drawn during transmission of the signal to the value of the total amount of the DC current drawn during non-transmission of the signal.
Claim 4
Dependent Claim
124 words
A transmission line communication system, comprising: a transmission line; means for applying a DC current to said transmission line; and a plurality of terminals connected to said transmission line in a multidrop fashion, each of said terminals being connected to said transmission line to draw a portion of said applied DC current, each of said terminals including means for varying the portions of said DC current drawn by said terminals to transmit a signal on said transmission line, and means for, when said signal is not being transmitted, maintaining a total amount of said DC current drawn from said transmission line at a value smaller than an average amount of said DC current drawn from said transmission line, when said signal is being transmitted.
Claim 5
Dependent Claim
45 words
The system of claim 4, wherein each of said plurality of terminals further includes: means for receiving a signal on the transmission line; and means for digitizing said received signal in accordance with a threshold level equal to an average value of the received signal.
Claim 6
Dependent Claim
132 words
The system of claim 4, wherein said means for varying the portions of said DC current drawn by said terminals includes: means for, during transmission of said signal, gradually increasing the amount of said DC current drawn from said transmission line from said value of said total amount of said DC current drawn when said signal is not being transmitted to said average amount of said DC current drawn when said signal is being transmitted; and means for, upon completion of transmission of said signal, gradually decreasing the amount of said DC current drawn from said transmission line from said average amount of said DC current drawn when said signal is being transmitted to said value of said total amount of said DC current drawn when said signal is not being transmitted.
References Cited (Backward Citations)
No citation records indexed.
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