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US3912876A Expired / Lapsed US ⏱️ 0.0 years remaining

Frequency division switching network

Assignee: International Standard Electric Corp
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Filing: 1974-03-29
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Granted: 1975-10-14
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Expires: 1994-03-29
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Abstract

Abstract Disclosed is a switching network usable in exchanges of a telecommunications system using frequency division switching. The input and output terminal circuits are interconnected by means of a transmitter to receiver coupling preferably using the air space between the transmitter and receiver as the medium linking the transmitter and receiver. The frequency of the receiver is tuned to the frequency of the transmitter by suitable control circuits. The switching is performed in an enclosed electromagnetically shielded room. Alternatively the principle could be employed with light waves using laser technology or by frequencies transmitted along solid wires.

Inventors

  • 👤 Jean Jacques Muller

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 17:13
CPC Classifications
H; H04; H04Q; H04Q11/00; H04Q11/02; H04B; H04B10/00; H04B10/80; H04B10/801; H04B10/802

Claims Analysis

Total Claims: 13
Claim 1
Independent Claim 151 words
A switching network for use in an exchange of a telecommunications system comprised of incoming, outgoing and local terminal circuits, said switching network comprised of a group of units including at least one radio transmitter unit and a second group including at least one radio receiver unit, said terminal circuits having connection to respective ones of said radio units foR completion of intermediate paths thereto, and means for tuning one of the radio units of one group to the same frequency as a radio unit of said other group to thereby complete a radio linkage between the tuned units, responsive to the completion of an intermediate path from a terminal circuit to a radio unit of one group to complete a path over said linkage to another terminal circuit, and wherein said units each have an antenna which is contained in an enclosed space electromagnetically isolating said antennae from outside interference.
Claim 2
Dependent Claim 151 words
A switching network for use in an exchange of a telecommunications system comprised of incoming, outgoing and local terminal circuits, said switching network comprised of a group of units including at least one radio transmitter unit and a second group including at least one radio receiver unit, said terminal circuits having connection to respective ones of said radio units foR completion of intermediate paths thereto, and means for tuning one of the radio units of one group to the same frequency as a radio unit of said other group to thereby complete a radio linkage between the tuned units, responsive to the completion of an intermediate path from a terminal circuit to a radio unit of one group to complete a path over said linkage to another terminal circuit, and wherein said units each have an antenna which is contained in an enclosed space electromagnetically isolating said antennae from outside interference.
Claim 3
Dependent Claim 57 words
A switching network as claimed in claim 1, wherein one group comprises a plurality of radio transmitter units each of which is equipped with antenna, and another group comprises a plurality of radio receiver units each of which is equipped with an antenna, and each of said radio units is coupled to one of said terminal circuits.
Claim 4
Dependent Claim 42 words
A switching network as claimed in claim 2, wherein said enclosing space comprises a switching room which is anechoic as far as radio transmissions are concerned and wherein the receiver unit antennas are in direct line of sight with transmitter unit antennas.
Claim 5
Dependent Claim 28 words
A switching network as claimed in claim 3, wherein the distance from any transmitter unit antenna to any receiver unit antenna inside the switching room is substantially constant.
Claim 6
Dependent Claim 41 words
A switching network as claimed in claim 4, wherein the shape of the switching room is elongated and wherein the transmitter unit antennas are arranged at one end of the room while receiver unit antennas are arranged at the other end.
Claim 7
Dependent Claim 51 words
A switching network as claimed in claim 2, wherein the frequency selected for a radio connection from a transmitter unit to a receiver unit is a fixed characteristic of one of those two units wherein the other unit is tuned to that frequency by a control means for the radio linkage.
Claim 8
Dependent Claim 25 words
A switching network as claimed in claim 2, wherein each terminal circuit is connected to both a predetermined transmitter unit and a predetermined receiver unit.
Claim 9
Dependent Claim 50 words
A switching network as claimed in claim 7, wherein there is control means with at least one local terminal circuit connected to the control means to enable signalling information to be exchanged between the control means and incoming and outgoing terminal circuits via the radio channel within the switching room.
Claim 10
Dependent Claim 39 words
A switching network as claimed in claim 2, wherein at least one terminal circuit is located outside the exchange and at least one of its radio units is connected by coupling to antennas located inside the exchange switching room.
Claim 11
Dependent Claim 160 words
A switching network for an exchange of a telecommunications system wherein there are a first plurality of terminal circuits connected to local telephone sets, and a second plurality of incoming and outgoing terminal circuits providing paths into and out of said exchange, a plurality of radio receiver units and a plurality of radio transmitter units, with said units tunable onto certain frequencies, each such terminal circuit including means for linking the respective circuit to a receiver unit or a transmitter unit, each unit having coupled thereto an antenna, an enclosing structure surrounding said antennae to isolate said antennae from the intrusion of radio waves from outside said structure, and means for tuning one unit of one plurality to a frequency to which a unit of the other plurality is tuned to complete a radio channel between the tuned units and complete a conversation path between a terminal circuit of said first plurality and a terminal circuit of said second plurality.
Claim 12
Dependent Claim 160 words
A switching network for an exchange of a telecommunications system wherein there are a first plurality of terminal circuits connected to local telephone sets, and a second plurality of incoming and outgoing terminal circuits providing paths into and out of said exchange, a plurality of radio receiver units and a plurality of radio transmitter units, with said units tunable onto certain frequencies, each such terminal circuit including means for linking the respective circuit to a receiver unit or a transmitter unit, each unit having coupled thereto an antenna, an enclosing structure surrounding said antennae to isolate said antennae from the intrusion of radio waves from outside said structure, and means for tuning one unit of one plurality to a frequency to which a unit of the other plurality is tuned to complete a radio channel between the tuned units and complete a conversation path between a terminal circuit of said first plurality and a terminal circuit of said second plurality.
Claim 13
Dependent Claim 60 words
A network as claimed in claim 10, wherein said channel is used for the one-way transmission of information between terminal circuits of said tuned units, and wherein a second transmitter unit and receiver unit are tuned to a second frequency for providing two-way transmission of information between the terminal circuits linked to the respective second transmitter unit ad receiver unit.

References Cited (Backward Citations)

US3295133A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1978-10-13 1979-04-14 1979-10-14 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1982-10-13 1983-04-14 1983-10-14 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1986-10-13 1987-04-14 1987-10-14 $7700.00 Window Closed / Lapsed

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