JPH0331306B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a connection between two telecommunication switching networks using different analog and digital transmission methods, and in particular to a connection between two communication switching networks using different transmission methods, analog and digital. This invention relates to a circuit that converts and transmits control signals for digital data network equipment.

Conventional technology Conventionally, when connecting analog telephone exchanges and digital data network equipment, conventional digital
Data network equipment did not have the ability to detect busy tone from analog telephone exchanges. Therefore, on the digital data switching network equipment side, in addition to the original line connection control circuit, there is a function to detect the busy tone signal from the analog telephone exchange, and a function to control call disconnection based on this detection. The addition of this functional device is not only complicated, but also has the disadvantage that it is difficult to add additional work to the existing digital data network equipment.

Problems to be Solved by the Invention The purpose of the present invention is to solve the above-mentioned drawback, that is, in the above-mentioned case, it is necessary to add a new control function device to the digital data exchange network equipment side. An object of the present invention is to provide a midrange signal conversion circuit.

Means for Solving the Problems In order to solve the above-mentioned problems, the present invention provides a system in which an analog telephone exchange and a digital data network device are connected by a 4-wire trunk circuit to make calls. A busy tone detection circuit recognizes the busy tone sent by the analog telephone exchange from the communication line of the wire trunk circuit, and the signal detected by this busy tone detection circuit is converted into a pulse signal and the signal is sent to the digital data network device. This system adopts a configuration in which a busy tone signal conversion circuit including a busy tone pulse generation circuit that sends out a side RG signal is inserted into a four-wire trunk circuit.

Operation Since the present invention is configured as described above, the busy tone signal from the analog telephone exchange can be converted into a pulse signal that can be detected by the digital data network device and transmitted.

Embodiments Next, embodiments of the present invention will be described with reference to the drawings.

Referring to FIG. 1, which shows a block diagram of one embodiment of the present invention, a busy tone signal conversion circuit 100 of the present invention is shown.
consists of a busy tone detection circuit 102 and a busy tone pulse generation circuit 104, and connects between the telephone exchange 200 and the digital data network device 201.
Connected to wire trunk circuit.

Next, the operation will be explained with reference to FIG. 1 and FIG. 2 showing an example of a signal sequence for busy tone signal conversion. First, when a call from a digital data network arrives at the telephone exchange 200 via the digital data network equipment 201, the terminating exchange generates a busy tone pulse by turning on the DL signal 106 when a call is possible. The circuit 104 passes the signal as it is and turns on the RG signal 105 of the digital data network device 201 to notify the completion of the connection, and from then on the call can be made.
If you want to notify that the call is not possible, please use DL signal 10.
Instead of changing 6, call line (transmission line) 10
1 to transmit a busy tone. Busy sound detection circuit 1
02 monitors the telephone line 101, and when a busy tone is detected, it notifies the busy tone pulse generation circuit 104 by means of a busy tone detection pulse 103. When the busy sound pulse generation circuit 104 receives the busy sound detection pulse 103 from the busy sound detection circuit 102, it connects to the DL line 106.
The connection with the RG line 105 is cut off, and instead, a signal is sent in pulse form from the busy tone pulse generating circuit 104 to the RG line 105 in a pulsed manner. However, the pulse width in this case is determined by the digital data network equipment.
A change in the RG line 105 is recognized as a connection completion, and then the required pulse width is recognized as a call disconnection request. Digital data network device 201 connects RG line 1
If a call disconnection request signal is recognized due to a change in 05, it notifies the caller on the digital data network side that the call is busy, and changes the DL signal 107 of the digital data network device 201 from on to off, The analog telephone exchange 200 is notified of the end of the call.

As described above, the connection interface between the analog telephone exchange 200 and the digital data network device 201 remains unchanged, the busy tone signal conversion circuit 100 is provided in the middle, the RG signal 105 is changed, and the digital data network device 201 In this way, the busy state can be transmitted from the telephone exchange 200 to the digital data network device 201.

Effects of the Invention As explained above, according to the present invention, by connecting a busy tone signal conversion circuit between a telephone exchange and a digital data network device, there is no need to define a special connection method between them. This has the effect of making it possible to connect networks using different transmission methods.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a busy tone signal conversion circuit according to an embodiment of the present invention, and FIG. 2 shows an example of a busy tone signal conversion sequence. 100...busy tone signal conversion circuit, 101...talk line (transmission line from telephone exchange), 102...busy tone detection circuit, 103...busy tone detection pulse, 1
04... Busy sound pulse generation circuit, 105... RG signal to digital data network equipment, 106...
DL signal from analog telephone exchange, 107...
DL signal from digital data network equipment, 10
8...RG signal to analog telephone exchange, 200
. . . analog telephone exchange, 201 . . . digital data network equipment.

Claims (1)

[Claims] 1. In a system where an analog telephone exchange and a digital data network device are connected by a four-wire trunk circuit to make a call, the busy tone transmitted by the analog telephone exchange is transmitted from the communication line of the four-wire trunk circuit. A busy tone detection circuit detects the busy tone, and a signal obtained by converting the signal detected by the busy tone detection circuit into a pulse signal is sent to the digital data network device by RG.
A busy tone signal conversion circuit comprising a busy tone pulse generation circuit that sends out a signal.