JPH05260541A - Optical exchange - Google Patents

Abstract

PURPOSE:To simultaneously supervise a subscriber's line signal by allowing the subscriber's line signal to branch on an optical subscriber's line for connecting a subscriber's terminal and an optical channel, and always inputting it to a detection circuit. CONSTITUTION:A subscriber's line signals transmitted through optical subscriber' s lines 14-16 from subscriber's terminals 01-03 are inputted into branch units 17-19. The branch units 17-19 allow the inputted subscriber's line signals to branch to an optical channel 07 and a signal supervisory part 23 in a state of optical signals. In the supervisory part 23, the subscriber's signals are detected by detecting circuits 20-22 and sent to a signal processor 24. The processor 24 discriminates the subscriber's line signal, based on the input signal, sends a result of discrimination to a control part 25, and the control part 25 sends a control signal to answer trunks 26-28, and sends out a dial tone, etc., to the subscriber's terminal. Moreover, the control part 25 sends the control signal to the optical channel 07, and exchanges the subscriber's line signal transmitted through the optical subscriber's lines 14-16 from the calling terminals 01-03 and the other party terminals 01-03 in a state of an optical signal.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical switch using an optical switch as an exchange switch element, and more particularly to a detection circuit for detecting a subscriber signal transmitted from a subscriber terminal via an optical subscriber line. Regarding the configuration of.

[0002]

2. Description of the Related Art A conventional optical switch is disclosed in Japanese Patent Application Laid-Open No. 2-1410.
As described in Japanese Patent Laid-Open No. 52-52, an optical communication path that does not depend on the type of signal (information speed, format, wavelength, etc.),
The call detection trunk is equipped with a call detection trunk that has a call signal detection function and a signal type identification function, a connection trunk for each signal type, and a control unit that controls optical communication paths and trunks and performs call processing. Some call types are identified by identifying the signal type and connecting a connection trunk corresponding to the calling terminal type to an optical subscriber line making a call using an optical communication path.

FIG. 7 is a diagram showing an example of the configuration of a conventional optical switchboard.

In the figure, 01 to 03 are subscriber terminals, and 04 to 0.
6 is an optical subscriber line, 07 is an optical communication path, 08 is a call detection trunk, 09 is a control unit, 10 and 11 are connection trunks, 1
Reference numeral 2 is a path connection control mechanism, and 13 is a control unit.

In FIG. 7, the call detection trunk 08 is
At the same time as detecting the calling signal, the signal type is identified and the calling terminal type is determined. Then, based on the result, the path connection control mechanism 12 switches the optical communication path 07 and connects the calling optical subscriber lines 04 to 06 to the connection trunks 10 and 11 corresponding to the calling terminal type. .. Then, the connection trunks 10 and 11 receive subscriber line signals such as dial signals transmitted from the calling side subscriber terminals 01 to 03, and from the optical switch side to the partner side subscriber terminals 01 to 03. It transmits response signals such as ringing signals.

[0006]

In the above prior art, in order to detect a calling signal transmitted as an optical signal, each of the subscriber terminals 01, 02, 03 is sequentially turned on.
The optical communication path 07 is controlled so as to be connected to the call detection trunk 08 in a time division manner one by one. As described above, since the subscriber lines are drawn one by one and sequentially scanned, there is a problem that a delay time is stochastically generated from the transmission of the call signal to the detection of the call.

A subscriber line signal transmitted from a subscriber terminal corresponding to an integrated services digital network (ISDN), which will be the mainstream of future communication, is stored in a control channel (D channel) and has a constant value. Such a subscriber line signal (D channel signal) is transmitted at the transmission interval.
When dealing with, the call cannot be detected unless simultaneous monitoring is performed. That is, there is a problem that a calling signal transmitted from a subscriber terminal that is pulled in and not scanned disappears without being detected.

Therefore, as described in JP-A-55-158795, a part of the optical signal is taken out from at least two or more optical subscriber lines of all the subscriber terminals accommodated in the optical switchboard. In some cases, the calling signal and the disconnection signal are detected by sequentially converting the optical signal into an electric signal by one detector. According to this technology,
Since the detector is shared by a large number of subscriber terminals, there is an effect that the size of the device can be reduced. However, calling signals and disconnection signals transmitted from the large number of subscriber terminals are sequentially scanned. Therefore, simultaneous monitoring cannot be performed.

An object of the present invention is to provide an optical switch capable of simultaneously monitoring subscriber line signals.

[0010]

In order to achieve the above object, the present invention provides an optical switch equipped with an optical communication path for performing a switching connection operation and a control section for controlling the optical communication path. A detection circuit provided for each subscriber terminal and for detecting a subscriber line signal transmitted from the subscriber terminal through the optical subscriber line, and a detection circuit provided for each accommodated subscriber terminal, A subscriber line signal transmitted via the subscriber line is provided with a branching device for branching the signal to the detection circuit and the optical communication path.

[0011]

The subscriber line signal (for example, a calling signal) is branched by the branching device on the optical subscriber line connecting the subscriber terminal and the optical communication path, and is always input to the detection circuit. Since the branching device and the detection circuit are provided for all subscriber terminals, all subscriber line signals transmitted from each subscriber terminal can be simultaneously monitored.

Further, by simultaneously monitoring the subscriber line signals, the disappearance of the D channel signal is eliminated when ISDN is supported.

[0013]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram of an optical switch according to an embodiment of the present invention.

In the figure, 01 to 03 are subscriber terminals, 07 is an optical communication path, 14 to 16 are optical subscriber lines, 17 to 19 are branching circuits, 20 to 22 are detection circuits, 23 is a signal monitoring section, and 24. Is a signal processing device, 25 is a control unit, and 26 to 28 are response trunks.

In the optical switch of this embodiment, subscriber line signals transmitted from the subscriber terminals 01 to 03 via the optical subscriber lines 14 to 16 are input to the branching units 17 to 19. The branching units 17 to 19 branch the input subscriber line signal to the optical communication path 07 and the signal monitoring unit 23 as they are as optical signals. In the signal monitoring unit 23, the detection circuits 20 to 22
Detects the input subscriber line signal, converts the subscriber line signal into an electric signal, and outputs the electric signal to the signal processing device 24. Signal processing device 24
Identifies the subscriber line signal from the input electrical signal,
The identification result is output to the control unit 25. The control unit 25 transmits the control signal to the response trunks 26 to 28, and the response trunks 26 to 28, based on the control signal, subscribe to the subscriber terminals 01 to.
A signal such as a dial tone is transmitted to 03.

Further, the control unit 25 performs call processing, outputs a control signal such as call path formation and disconnection to the optical call path 07,
Subscriber line signals (communication) transmitted from the calling subscriber terminals 01 to 03 and the partner subscriber terminals 01 to 03 via the optical subscriber lines 14 to 16 using the optical communication path 07 performing the switching connection operation. (Information) is exchanged as an optical signal.

Next, the operation from the subscriber terminal 01 to the subscriber terminal 03 in FIG. 1 until the subscriber terminal 01 and the subscriber terminal 03 enter the call state will be described with reference to FIG.
~ It demonstrates using FIG.

FIG. 2 shows a state in which the calling signal transmitted from the subscriber terminal 01 is branched by the branching device 17 and detected by the detection circuit 20, and FIG. 3 is controlled by the signal processing device 24. FIG. 4 shows a state in which signals such as dial tone, ringing tone, and busy tone are transmitted from the response trunk 26 to the subscriber terminal 01 via the unit 25. FIG. 4 shows the subscriber terminal 01 and the subscriber terminal 03. Indicates a busy state.

As shown in FIG. 2, when a subscriber makes a call from the subscriber terminal 01, a calling signal is transmitted via the optical subscriber line 14. The branching machine 17 sends the calling signal to the optical communication path 0.
7 and the detection circuit 20. The detection circuit 20 detects the calling signal, and the signal processing device 24 identifies the calling signal and identifies that the subscriber terminal 01 has called.

Subsequently, as shown in FIG. 3, the signal processing device 24 outputs the identification result to the control unit 25. Control unit 25
Sends a control signal indicating transmission of a dial tone to the response trunk 26, and the response trunk 26 transmits a dial tone to the subscriber terminal 01.

When the subscriber of the subscriber terminal 01 who receives the dial tone dials the subscriber number of the subscriber 03, a dial signal is transmitted through the optical subscriber line 14 as in the example of FIG. .. The branching device 17 sends the dial signal to the optical communication path 07.
To the detection circuit 20. The detection circuit 20 detects the dial signal, and the signal processing device 24 identifies the dial signal and identifies that the subscriber terminal 01 dials the subscriber number of the subscriber terminal 03.

Subsequently, as in the example of FIG. 3, the signal processing device 24 outputs the identification result to the control unit 25. Control unit 25
Transmits a control signal indicating the subscriber terminal 03 to be connected to the answer trunks 26 and 28, the answer trunk 26 sends a ring tone to the subscriber terminal 01, and the answer trunk 28 sends a call signal to the subscriber terminal 03. To send. At this time, subscriber 0
When 3 is busy, the control unit 25 transmits a control signal indicating that the busy tone is transmitted to the response trunk 26, and the response trunk 26 transmits the busy tone to the subscriber terminal 01.

The subscriber terminal 03 that receives the ringing signal rings the bell, and when the subscriber of the subscriber terminal 03 that hears the bell answers, the subscriber terminal 03 responds via the optical subscriber line 16 as in the example of FIG. A terminal response signal is sent. The branching device 19 branches the terminal response signal into the optical communication path 07 and the detection circuit 22.
The detection circuit 22 detects the terminal response signal, and the signal processing device 24 identifies the terminal response signal and identifies that the subscriber terminal 03 has responded.

Therefore, as shown in FIG. 4, the signal processing device 24 outputs the identification result to the control unit 25. Control unit 25
Transmits a control signal indicating that the subscriber terminal 01 and the subscriber 03 are connected to the response trunks 26 and 28 and the optical communication path 07. Upon receiving the control signal, the response trunks 26 and 28 stop the ringing tone and ringing signal transmitted to the subscriber terminals 01 and 03. Further, when the optical communication path 07 receives the control signal, the optical subscriber line 14 of the subscriber terminal 01 is received.
The communication information transmitted from the subscriber terminal 03 to the response trunk 28 corresponding to the subscriber terminal 03 is transmitted from the optical subscriber line 16 of the subscriber terminal 03 via the splitter 19. The incoming communication information is connected to the response trunk 26.

When disconnecting from the subscriber terminals 01 and 03, the disconnection signal is detected by the detection circuit 20 and the detection circuit 22, and after identification by the signal processing device 24, a response trunk is issued by a control instruction from the control unit 25. 28 and 26 transmit disconnection signals to the subscriber terminals 03 and 01.

As described above, according to this embodiment,
It is possible to simultaneously monitor all subscriber line signals transmitted from subscriber terminals. Therefore, instead of sequentially scanning the subscriber line signals, by monitoring all the subscriber line signals at the same time, the disappearance of the D channel signal is eliminated when the ISDN subscriber line signal is supported, and the signal is transmitted from the subscriber terminal. It is possible to detect the incoming subscriber line signal without missing it.

Further, in the case of the scan detection method which is the conventional detection method, in order to prevent the disappearance of the D channel signal, 1
Although it is necessary to limit the number of subscriber terminals within a range that can be monitored within one scan time, the simultaneous monitoring method according to this embodiment can increase the number of subscriber terminals.

Next, another embodiment of the present invention will be described with reference to FIG.

FIG. 5 is a block diagram of an optical switch according to another embodiment of the present invention.

The optical switch of the present embodiment is the same as the optical switch shown in FIG. 1, except that subscriber terminals 01 to 03 and branch switches 17 to 1 are used.
9, the optical subscriber lines 14 to 16 of the two upward and downward two lines are multiplexed, and the optical subscriber line 0 of the bidirectional one line 0
The multiplexers 29 to 31 which are grouped in 4 to 06 are provided, and the operation principle is the same as that of the embodiment shown in FIG.

By providing the multiplexers 29 to 31, the optical subscriber lines 04 to 06 from the subscriber terminals 01 to 03 are provided.
, It is possible to use one bidirectional line instead of separate lines for upstream and downstream.

Next, another embodiment of the present invention will be described with reference to FIG.

FIG. 6 is a block diagram of an optical switch according to another embodiment of the present invention.

The optical switch of the present embodiment is the optical switch shown in FIG. 1 in which the detection circuit 2 is provided for each of the subscriber terminals 01 to 03.
0 to 22 are provided, but the detection circuits 20 and 21 are provided for each of two or more subscriber terminals, and the operation principle is the same as that of the embodiment shown in FIG. However, the difference is that the detection circuits 20 and 21 sequentially scan and detect subscriber line signals (D channel signals) transmitted from the corresponding subscriber terminals via the optical subscriber lines 14 to 16. It is a point. However, when the subscriber terminals 01 to 03 are ISDN-compatible subscriber terminals, the number of subscriber terminals for which the detection circuits 20 and 21 detect the D channel signal is set within one scan time. It is necessary to limit it within the range that can be monitored by. That is, the detection circuits 20 and 2
1 detects D channel signals transmitted from a number of subscriber terminals capable of completing one scan within a time shorter than the D channel transmission interval.

[0036]

As described above, according to the present invention,
It is possible to simultaneously monitor all subscriber line signals transmitted from subscriber terminals. Therefore, when the subscriber line signal of ISDN is supported, it is possible to detect the disappearance of the D channel signal without missing the subscriber line signal.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an optical switch according to an embodiment of the present invention.

FIG. 2 is a diagram showing an operation principle when a call is made to a subscriber terminal in the present embodiment.

FIG. 3 is a diagram showing an operation principle during transmission of a dial tone in the present embodiment.

FIG. 4 is a diagram showing an operation principle during a call in the present embodiment.

FIG. 5 is a configuration diagram of an optical switch according to another embodiment of the present invention.

FIG. 6 is a configuration diagram of an optical switch according to another embodiment of the present invention.

FIG. 7 is a block diagram of a conventional optical switchboard.

[Explanation of symbols]

01 to 03 ... subscriber terminal, 04 to 06 ... optical subscriber line (bidirectional), 07 ... optical communication line, 08 ... call detection trunk, 0
9 ... Control device, 10-11 ... Connection trunk, 12 ... Path connection control mechanism, 13, 25 ... Control part, 14-16 ... Optical subscriber line (one direction), 17-19 ... Brancher, 20-22 ...
Detection circuit, 23 ... Signal monitoring unit, 24 ... Signal processing device, 2
6-28 ... Response trunk, 29-31 ... Multiplexer.

Claims (4)

[Claims] 1. An optical switch equipped with an optical communication path for performing a switching connection operation and a control section for controlling the optical communication path, which is provided for each accommodated subscriber terminal and connects an optical subscriber line from the subscriber terminal. A detection circuit for detecting a subscriber line signal transmitted via the subscriber line signal, which is provided for each accommodated subscriber terminal and which is transmitted from the subscriber terminal via the optical subscriber line, An optical switch, comprising: the detection circuit and a branching device that branches into the optical communication path. 2. The optical switch according to claim 1, further comprising a multiplexer for multiplexing the two lines when the optical subscriber line is composed of two lines, an up line and a down line. An optical switch that is characterized. 3. The optical switch according to claim 1 or 2, further comprising a response trunk provided for each accommodated subscriber terminal and transmitting a response signal to the subscriber terminal via an optical subscriber line. The control unit controls the corresponding response trunk to transmit the response signal based on the subscriber line signal detected by the detection circuit. 4. An optical switch equipped with an optical communication path for performing a switching connection operation and a control unit for controlling the optical communication path, when the subscriber terminal accommodated is an ISDN compatible subscriber terminal. One or more detection circuits for sequentially scanning and detecting at least two or more subscriber line signals transmitted from the subscriber terminal via the optical subscriber line, and provided for each of the accommodated subscriber terminals, The subscriber line signal transmitted from the subscriber terminal via the optical subscriber line is provided with a branching device for branching to a corresponding detection circuit and the optical communication path, and the detection circuit is the subscriber line signal. An optical switch characterized by detecting subscriber line signals transmitted from a number of subscriber terminals capable of completing one scan within a time shorter than the transmission interval of the control channel storing therein.