JPH047623B2 - - Google Patents

Description

[Detailed Description of the Invention] (a) Technical Field of the Invention The present invention relates to an automatic switching system, and in particular to a subscriber line monitoring system that monitors call status from a subscriber line compatible device installed corresponding to a subscriber. Regarding improvements.

(b) Background of the Technology Conventional telephone exchanges only selectively connect a called subscriber based on the called subscriber's telephone number sent from the calling subscriber, and did not particularly require the calling subscriber's telephone number. However, in recent years, new services such as facsimile communication services and data communication services that also require the calling subscriber's telephone number are being introduced.

FIG. 1 is a diagram showing an example of a facsimile communication system to which the present invention is applied. In Figure 1, subscribers who use facsimile communication services
A subscriber line compatible device SLE is connected to the subscriber line SL that accommodates the SUB in the automatic exchange EX. The control unit CTL in the subscriber line compatible equipment SLE
SUB phone numbers are stored in advance. Subscriber
When the SUB makes a call and dials a special number (for example, 161) for facsimile communication service, the automatic exchange EX connects the calling subscriber SUB to the outgoing trunk OGT leading to the facsimile communication trunk exchange TS-FX, and The special number is sent to the facsimile communication trunk exchange TS-FX via the outgoing trunk OGT. The facsimile communication relay exchange TS-FX, which has received the special number, sends a response signal back to the automatic exchange EX. Out trunk
OGT is a relay exchange for facsimile communication TS-
Upon receiving the response signal sent back from FX, the subscriber
Change the potential of the subscriber line relative to SUB (for example, to ground potential on both lines). In the subscriber line compatible device SLE, the line monitoring unit LMU monitors the potential of the subscriber line SL, and when the potential change is detected, the control unit
Start CTL. The activated control unit CTL operates the contact point s and also connects the subscriber accumulated in advance.
The SUB telephone number is transmitted to the single-digit PB signal sending unit PBS, which converts it into a PB signal and sequentially sends it to the automatic exchange EX. The telephone number based on the PB signal is transmitted to the facsimile communication relay exchange TS-FX via the automatic exchange EX. After sending the telephone number of the subscriber SUB, the control unit CTL and contact s of the subscriber line support device SLE are restored, and from now on the subscriber
The telephone number of the called subscriber sent by the SUB is transmitted to the facsimile communication relay exchange TS-FX via the automatic exchange EX.

(c) Prior art and problems FIG. 2 is a diagram showing an example of a conventional subscriber line monitoring method in this type of subscriber line compatible equipment.
FIG. 3 is a diagram illustrating various signal waveforms in FIG. 2. In Figure 2, the subscriber number storage section
The IDR contains the telephone number of the subscriber SUB (hereinafter referred to as the subscriber number id, each digit is a 9-digit number consisting of numbers d1 to d9).
digits) are stored in advance. Line monitoring department
The LMU monitors potential changes on the subscriber line SL,
The subscriber SUB identifies whether the handset is up or down and transmits it to the subscriber status determination unit SUP as monitoring information a, and also outputs the outgoing trunk OGT (Figure 1).
The subscriber state determination unit identifies whether or not a response signal based on the ground potential of both lines is returned from the subscriber status as monitoring information b.
Communicate to SUP. The subscriber status determination unit SUP detects the calling of the subscriber SUB based on the monitoring information a transmitted from the line monitoring unit LMU, and further detects that a response signal is returned from the facsimile communication relay exchange TS-FX based on the monitoring information b. When this is identified, the transmission sequence control unit SQC is activated. The transmission sequence control unit SQC sequentially transmits the digit designation signal st to the subscriber number storage unit IDR from the first digit to the ninth digit at a predetermined period (eg, 130 millisecond period). Subscriber number storage unit that received the digit designation signal st
The IDR sequentially transmits the pre-stored subscriber numbers id from the first digit d1 to the ninth digit d9 to the PB signal sending unit PBS according to the instruction of the digit designation signal st. P.B.
The signal sending unit PBS converts the first digits d1 to the ninth digits d9 of the subscriber number ID sequentially transmitted from the subscriber number storage unit IDR into PB signals, and sends the signals to the automatic exchange.
Send to EX. Note that the joint point s continues to operate. Also, the transmission sequence control unit SQC
transmits a determination timing signal t to the subscriber state determination unit SUP, and causes the reception determination of monitoring information a and b to be stopped. When the ninth digit d9 of the subscriber number ID is sent by the PB signal, the contact s is restored, and the transmission sequence control unit SQC is activated by the subscriber status determination unit.
Stop sending out the determination timing signal t to SUP. Therefore, the subscriber status determining unit SUP resumes determining whether the monitoring information a and b are received.

As is clear from the above explanation, in the conventional subscriber line monitoring system, the subscriber line corresponding equipment SLE
While the subscriber number ID is being sent from the subscriber line SL (approximately 1.2 seconds (130 x 9 milliseconds) according to the previous example), the subscriber line support equipment SLE stops monitoring the call status on the subscriber line SL. was. So during the subscriber SUB
Even if the caller hangs up and abandons the call,
The subscriber line support device SLE continues to send the subscriber number ID up to the ninth digit d9, during which time the subscriber SUB is unable to make the next call, and the automatic exchange EX and the facsimile communication trunk exchange TS-FX are disabled. There were some drawbacks that were held back.

Another method is to provide a subscriber status monitoring circuit independently of the line monitoring unit LMU while sending the subscriber number ID from the PB signal sending unit PBS. It is also possible to connect to the subscriber line and independently detect changes in the subscriber status, and activate the transmission sequence control unit to stop the transmission process of the subscriber number only when abandonment occurs. The subscriber line monitoring method requires complicated control procedures, resulting in a loss of economic efficiency.

(d) Purpose of the Invention The purpose of the present invention is to eliminate the shortcomings of the conventional subscriber line monitoring system as described above, and to immediately monitor the subscriber line in the event of an abnormal termination of calling while transmitting the subscriber number from the subscriber line compatible device. The object of the present invention is to realize a means for stopping the transmission of numbers and releasing calls without impairing economic efficiency or complicating control procedures.

(e) Structure of the Invention This object is to provide a monitoring means connected to a subscriber line for detecting a call from a corresponding subscriber and monitoring the status of the calling subscriber; A subscriber line compatible device comprising number sending means for sequentially sending a single digit calling subscriber number to an exchange accommodating the subscriber line at a predetermined pause interval when a call is detected. wherein the number sending means notifies the monitoring means of a period during which each digit of the calling subscriber number is sent, and suspends monitoring of the status of the calling subscriber only during the sending period of each digit of the calling subscriber number; If the monitoring means detects that the calling subscriber has abandoned the calling subscriber while the number sending means is sending out the calling subscriber number, the monitoring means causes the number sending means to immediately stop sending the calling subscriber number; This is achieved by providing a sequence control means for notifying the exchange of the abandonment.

That is, according to the present invention, the subscriber line compatible device:
It is possible to monitor the status of the calling subscriber while the subscriber number is being sent without separately installing a subscriber status monitoring circuit or complicating the control procedure, and when it is detected that the subscriber's call is abandoned, the call can be stopped immediately. release the
The subscriber's next call can then be made, and the automatic switchboard is also prevented from being put on hold.

(f) Embodiment of the invention An embodiment of the invention will be described below with reference to the drawings. FIG. 4 is a diagram showing a subscriber line monitoring system according to an embodiment of the present invention, and FIGS. 5 and 6 are diagrams illustrating various signal waveforms in FIG. 4.
The configuration of the subscriber line compatible device according to the embodiment of the present invention shown in FIG. 4 is similar to the conventional subscriber line compatible device shown in FIG. Status determination section
The functions provided by SUP' are different from those of the transmission sequence control unit SQC and subscriber status determination unit SUP in FIG. In Figures 4 and 5, the line monitoring section
As mentioned above, LMU is a subscriber from automatic exchange EX.
It monitors potential changes in the communication line leading to SUB, and transmits monitoring information a and b to subscriber status determination unit SUP'. Similarly to the above, the subscriber status determination unit SUP' detects a call from the subscriber SUB based on the monitoring information a returned from the line monitoring unit LMU, and further detects the call originating from the facsimile communication trunk exchange TS-FX based on the monitoring information b. When it is determined that a response signal has been returned via exchange EX, the transmission sequence control unit
Start SQC′. Transmission sequence control section
As mentioned above, SQC′ sends a digit designation signal to the subscriber number storage unit IDR at a predetermined period (130 millisecond period in the previous example).
st is transmitted sequentially from the 1st digit to the 9th digit, and the subscriber number ID is sequentially transmitted from the 1st digit d1 to the 9th digit d9 to the subscriber number storage unit IDR and PB signal sending unit PBS.
Send by PB signal. Meanwhile, line monitoring department
The LMU can always monitor the call status on the subscriber line SL, except when the PB signal is being sent from the PB signal sending unit PBS. In addition, the transmission sequence control unit SQC' transmits a determination timing signal t' to the subscriber status determination unit SUP', and monitors information only while the PB signal transmission unit PBS is transmitting each number d1 to d9 of the subscriber number ID. The reception judgment of a and b is canceled. The subscriber status determination unit SUP' determines the subscriber number id
Each time each digit d1 to d9 of has been sent, monitoring information a and b are tried to be determined, and when it is detected that the subscriber SUB has put down the handset twice or more in a row, the subscriber SUB makes a call. It is determined that the transmission sequence control unit SQC′ has been abandoned, and the activation of the transmission sequence control unit SQC′ is stopped. As a result, the transmission sequence controller
SQC' immediately stops sending the digit designation signal st to the subscriber number storage unit IDR, stops sending the subscriber number id, and restores the contact point s. As a result, automatic exchange EX immediately releases the call from subscriber SUB. FIG. 6 shows that after the subscriber status determination unit SUP' sends the numbers d4 and d5 of the subscriber number ID,
Indicates that the SUB has detected that the handset has been put down.

As is clear from the above description, according to this embodiment, the subscriber line support device SLE monitors the call status on the subscriber line SL even while sending the subscriber number ID,
When a premature abandonment of subscriber SUB is detected, transmission of the subscriber number ID is immediately stopped and the call can be released. Therefore, the automatic exchange EX and the facsimile communication trunk exchange TS-FX are prevented from being put on hold, and the next call can be handled immediately from the subscriber SUB.

Furthermore, since control is performed using the same circuit, the control procedure can be simplified and realized economically.

Note that FIGS. 4 and 5 are only one embodiment of the present invention, and for example, the subscriber number ID is not limited to 9 digits, and many other modifications may be considered, but any Even in this case, the effects of the present invention remain the same.
Further, the configuration of the subscriber line compatible device SLE is not limited to that shown in the drawings, and many other modifications may be considered, but the effects of the present invention will not change in any case. Furthermore, the interruption of transmission of the subscriber number ID is not limited to the premature abandonment of the subscriber SUB, and many other variations can be considered, such as a failure of the package that constitutes the subscriber line compatible device SLE. In either case, the effects of the present invention remain the same. Furthermore, the object of the present invention is not limited to facsimile communication systems, and its effects will remain the same even if it is applied to all communication systems that require subscriber line compatible equipment SLE.

(g) Effects of the Invention As described above, according to the present invention, if a call is abnormally terminated while a subscriber number is being sent from the subscriber line compatible device, the sending of the subscriber number can be immediately stopped and the call can be released. This makes it possible to immediately respond to the next call from the subscriber, and also to prevent the automatic exchange from being put on hold.

Furthermore, when a subscriber number transmission process is executed from a subscriber line compatible device, the subscriber status determination and transmission sequence control can be executed in the same circuit, which is economical.

[Brief explanation of drawings]

FIG. 1 is a diagram showing an example of a facsimile communication system to which the present invention is applied, FIG. 2 is a diagram showing an example of a conventional subscriber line monitoring system, and FIG. 3 is a diagram illustrating various signal waveforms in FIG. 2. 4 is a diagram showing a subscriber line monitoring system according to an embodiment of the present invention,
5 is a diagram illustrating various signal waveforms in FIG. 4, and FIG. 6 is a diagram illustrating various signal waveforms in FIG. 4. In the figure, a and b are monitoring information, CTL is the control unit, d1 to d9 are the 1st to 9th digits, EX is the automatic exchange, id is the subscriber number, LMU is the line monitoring unit, and OGT is the outgoing trunk. , OS is the output sender, PBS is the PB signal sending unit, s is the contact point, SL is the subscriber line, SLE is the subscriber line compatible equipment, SQC and
SQC′ is the transmission sequence control unit, st is the digit designation signal,
SUB represents a subscriber, SUP and SUP' represent subscriber status determination units, and t and t' represent determination timing signals.

Claims (1)

[Claims] 1 monitoring means connected to a subscriber line, detecting a call from a corresponding subscriber and monitoring the status of the calling subscriber; and when the monitoring means detects a call from the subscriber, A subscriber line compatible device comprising number sending means for sequentially sending a calling subscriber number to a single digit at a predetermined pause interval to an exchange accommodating a subscriber line, wherein the number sending means The monitoring means is notified of the period for transmitting each digit of the subscriber number, the status monitoring of the calling subscriber is stopped only during the period of transmitting each digit of the calling subscriber number, and the number sending means If the monitoring means detects that the calling subscriber has abandoned the calling subscriber number while transmitting the calling subscriber number, the monitoring means causes the number sending means to immediately stop sending the calling subscriber number and notifies the exchange of the premature abandonment. A subscriber line monitoring system characterized by providing a sequence control means.