JPH037463A - Digital public telephone set - Google Patents

Abstract

PURPOSE:To attain automatic dialing while using an automatic dialer having a PB signal transmission function from a transmitter used in an analog public telephone set by allowing a selection signal reception analysis section to absorb the difference of a line selection signal system between a digital public telephone set and an analog public telephone set. CONSTITUTION:A changeover section 9 consists of an input changeover means 9a, an input/output changeover means 9b and an output changeover means 9c. Then a PB signal as a line selection signal used for an existing analog interface terminal equipment 200 is dialed through the existing analog interface terminal equipment 200 selecting an input source to a line selection signal reception analysis section 7 and a CODEC and an output destination of a tone generating means 8 according to the operation procedure of the user and the dialing of the PB signal via a transmitter of the public telephone set 100 is attained. Thus, automatic dialing is attained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a digital public telephone set connected to a digital interface that transmits and receives telephone calls and subscriber line signals in digital signals between a terminal and a station equipment.

(Prior art) Conventional public telephones use analog interfaces, but do not have interfaces for connecting external portable data terminals or auto-dial devices. Autodial devices accomplished their purpose by sending a voiceband signal to the handset of a public telephone.

In portable data terminals, an audio coupler is mechanically fitted into the handset and the data is modulated into the audio band to transmit and receive data. The auto-dial device takes advantage of the fact that most analog public telephones use a PB signal as a line selection signal, converts the auto-dial data into a PB signal, and outputs it to the handset to achieve the purpose. are doing.

Although not a public telephone, there is generally a terminal adapter as a related device for converting an existing terminal for an analog interface into a digital interface and connecting it. This will be explained with reference to FIG.

In FIG. 2, 200 is an existing analog terminal used by connecting to the existing analog network, and 300 is a digital exchange. 400 is a terminal-side terminal device (digital service unit) of the digital compatible exchange 300, and 500 is a terminal adapter.

1~8゜14~1 constituting the terminal adapter 500
Since each part of 6 will be explained later in the embodiment of the present invention, an overview of the overall operation will be described here.

Analog terminal 200 via terminal adapter 500
When the input signal of the PB flaw signal is sent from here, it is internally converted into a digital signal and sent to the digital compatible exchange 300. Digital compatible exchange 30
Conversely, the transmission signal from 0 is converted into an analog signal by the terminal adapter 500 and sent to the analog terminal 200.

In this case, since the terminal adapter 500 does not have a billing function, the analog interface side of the terminal adapter 500 is modified so that it can output billing signals for analog public telephones, and the digital interface side of the terminal adapter 500 is modified to be able to receive billing signals from digital public telephones. It is conceivable to modify the software and connect an analog public telephone to a digital interface via a modified terminal adapter, but this would involve receiving and analyzing the analog line selection signal, converting it to a dialing signal for the digital interface, and sending it out. There are still no public telephones with a digital interface to which terminals with existing analog interfaces 500 can be connected.

(Problem to be solved by the invention) Although public telephones for analog interfaces may have existing terminal connection interfaces,
The only method considered is to make a call from a public phone, connect to the other party, and then switch to the connected terminal. This is because in analog interfaces, both call control signals and billing signals are not coded as in digital interfaces, so if a call is made from an existing connected terminal, the public telephone must have the same functionality as an exchange. This is because the scale of hardware and software such as mechanical switches such as relays and their control becomes large. If you modify the terminal adapter, you can only use the functions of an analog public telephone;
This method has the disadvantage that the scale of the circuit required to generate a polarity reversal signal, which is a billing signal for analog public telephones, becomes large. In addition, with digital interfaces, the line selection signal (dial) itself is coded, and auto dialing, which transmits the PB signal that could be used with analog interfaces as a line selection signal, is transmitted directly from the handset. Since the method itself is different, it cannot be used as is.

(Means for Solving the Problems) A digital public telephone according to the present invention includes a selection signal reception and analysis section that receives and analyzes a line selection signal for an analog interface, and converts the subscriber line signal for the analog interface to a predetermined level. A level conversion unit that transmits and receives
An input switching means for switching the input to the selected signal reception analysis section between the level converter or the transmitter, and an input switching means for switching the input to the selected signal reception analysis section between the level converter and the transmitter; input/output switching means for switching, output switching means and input switching means for switching the output of the tone generation section to the level conversion section or the transmitter, and input/output switching means for switching.

It has a changeover switch that instructs the changeover of the output changeover means.

(Function) In the present invention, the PB defect signal is used as a line selection signal in an existing analog interface terminal, and the input source to the line selection signal reception analysis unit and codec and the tone generation means are changed according to the user's operating procedure. It is possible to make a call from an existing analog interface terminal by switching the output light of the telephone, and to dial using a PB signal via the transmitter of a digital public telephone.

(Embodiment) FIG. 1 shows an embodiment of a digital public telephone according to the present invention. In this figure, 100 is a digital public telephone;
200 is a terminal used by connecting to the existing analog network; 30
0 is a digital exchange. 400 is a terminal-side terminal device (digital service unit) of the digital compatible exchange 300.

Next, details of the digital public telephone 100 will be explained. 1 is a microprocessor that controls the digital public telephone 100. 2 is a digital public telephone 1
00 is a memory for storing a control program, and 3 is a working memory necessary for the microprocessor 1 to operate. 4 assembles and disassembles frames of digital signals, extracts a signal channel (B channel) and a control channel (D channel), and passes the D channel signal in parallel to the microprocessor 1 or from the microprocessor 1. This is a digital signal control unit that puts the parallel signals of 1 and 2 on the D channel. 5 is the digital service unit 400 and the digital signal control section 4;
This is a driver/receiver for matching the signal levels of the 6 is a codec that converts digital signals into analog signals and vice versa. Reference numeral 7 denotes a selection signal reception and analysis section that receives the input analog line selection signal, analyzes it, converts it into a code, converts it into a parallel signal, and outputs it to the microprocessor 1. Reference numeral 8 indicates various sounds used in this digital public telephone 100 (dial tone, busy tone).

This is a tone generation unit that generates PB tones, etc.). Reference numeral 9 denotes a switching section using a switching switch such as a mechanical switch or a semiconductor switch, and includes input switching means 9a, input/output switching means 9b, and output switching means 9c. 1
0 is a handset of the digital public telephone 100, which consists of a handset and a handset. 11 is a hook switch,
12 is a display, and 13 is a dial. 14 is an analog terminal connection port for connecting an existing analog terminal. Reference numeral 15 denotes a level converter that converts the electrical level of the analog line interface to a level that can be manually input to the codec 6. 16 is the line Ll of the analog terminal 2o○
, L2 status (loop closure, loop open, etc. call control status)
This is an analog subscriber signal detection unit that monitors and detects the status.

17 is a switching button, which is connected to the microprocessor 1. 18 is the microprocessor 1
Billing processing as a public telephone based on instructions from
This is the billing processing unit that performs the following. Reference numeral 19 is a power supply that supplies the power necessary for the operation of each part of the public telephone and the power necessary for the analog interface, and 20 is a connection detection sensor that detects whether or not the analog terminal 200 is connected to the analog terminal connection port 14. It is something to do.

Hereinafter, the operation of the digital public telephone 100 according to the present invention will be explained in detail.

When the power source 19 is turned on, the hook switch 11 is turned on (the handset 1o is disconnected), or the analog terminal 2°O is connected to the analog terminal connection port 14, and the changeover switch 17 is turned on. wait for. When the hook switch 11 is turned on first, the switching unit 9 is switched to the handset 10 side (solid line in the figure) and the system waits until notification from the billing processing unit 18 that a telephone card or coin has been inserted.

Therefore, when the handset 10 is removed first, the codec 6, the selection signal reception analysis section 7. The tone generator 8 is connected to the receiver as shown by the solid line in the figure. Billing processing unit 1
When a notification is sent from 8 that a calling card or coin has been inserted, a check is made to see if the information is of sufficient value to permit the call, and if it is OK, a message is sent to encourage dialing. Displayed on the display 12. Normally, when a user presses the dial 13 attached to the digital public telephone 100, the microprocessor 1 receives the dial 13, includes it in the call setting signal as a line selection signal for the digital line interface, and then outputs the digital signal. It is sent to the control unit 4. Here, dial 1
Instead of pressing 3, press the PB sound output section of an auto-dial device (not shown) that can output a dial signal and a PB damage signal against the mouthpiece of the handset 1o of the digital public telephone 100, and then press the When a PB defect signal for line selection is issued, the result is as follows.

A selection signal reception analysis section 7 is provided at the output of the handset 10.
is connected. The PB number from the auto-dial device pressed against the mouthpiece of the handset 10 is input to the selection signal reception analysis section 7 through the handset.The 0 selection signal reception analysis section 7 calculates the input PB signal frequency. The combination is a specified code (O~9. #, *, A, B, C,
D), and microprocessor 1
The results of this analysis (signal code) will be notified to the The microprocessor 1 includes this signal code in the call setting signal of the digital interface as a line selection signal in the same manner as the dial code from the dial 13, and sends it to the digital signal control unit 4. At this time, the PB from the transmitter
Digital public telephone 10 while the signal is being input.
It is possible to ignore the input from the 0 dial 13, or to recognize it at the same time, superimpose both, and transmit it as a line selection signal.

On the other hand, first connect the analog terminal 20 to the analog terminal connection port 14.
When the connection detection sensor 20 detects that 0 is connected and the changeover switch 17 is turned on,
The switching section 9 is switched to the level conversion section 19 side (indicated by the broken line in the figure), and the charging processing section waits until it is notified that a telephone card or coin has been inserted. Therefore, when the analog terminal 200 is first connected to the analog terminal connection port 14 and the changeover switch 17 is pressed, the codec 6, the selection signal reception analysis section 7. The tone generating section 8 is connected to a level converting section 15 for analog terminal connection.

When a notification that a telephone card or coin has been inserted is sent from the billing processing unit 18, a check is made to see if the information is of sufficient value to permit a call, and if it is OK, the connected analog terminal is 200 is allowed to make a call, and the call is displayed on the display 12.

The user uses the functions of his/her analog terminal 200 connected to the analog terminal connection port 14 to close the loop. Digital public telephone 100 detects the closure of this loop using analog subscriber signal detection section 16 and notifies microprocessor 1 of this.

The microprocessor 1 controls the tone generator 8 to generate a dial tone. This dial tone is transmitted to the existing analog terminal 200 via the level converter 15,
The analog terminal 200 outputs a line selection signal as a PB defect signal.

A code (a code (
0-9. #, *, A, B.

C, D) and notifies the microprocessor 1 of the analysis result (signal code). The microprocessor 1 includes this signal code in the call setting signal of the digital interface as a line selection signal in the same manner as the dial code from the dial 13, and sends it to the digital signal control unit 4.

Similarly, call control signals other than the call connection of the existing analog terminal 200 are also detected by the analog subscriber signal detection section 16, replaced with call control signals of the digital interface, and sent to the digital signal control section 4, and transmitted to the digital network. Perform cutting, etc. Conversely, the digital interface call control signal from the network is converted into an analog signal by the digital public telephone 100 and transmitted to the analog terminal.

For example, when disconnected from the network, the digital signal controller 4 disconnects the signal channel, and the tone generator 8
The microprocessor 1 instructs the microprocessor 1 to generate a busy tone. Analog terminal 200 learns from this busy tone that it has been disconnected from the rope, and releases the loop.

In addition to the above steps, the procedure for connecting a call is to connect the existing analog terminal 200 to the analog terminal connection port 14, pick up the handset 1o, make a call using the dial 13 of the digital public telephone 100, and call the other party. There is also a method of confirming that the connection is made and then pressing the changeover switch 17 to change the codec 6 to the level conversion unit 15. In this case, when the changeover switch 17 is pressed when the other party answers, the changeover unit 9 is changed to the level conversion unit 15. All you have to do is switch.

(Effects of the Invention) As explained in detail above, the present invention includes a selection signal reception analysis section that receives and analyzes a line selection signal for an analog interface, and a selection signal reception analysis section that converts the subscriber line signal for the analog interface to a predetermined level. A level converter for transmitting and receiving, an input switching means for switching the input to the selected signal reception analysis unit between the level converter or the transmitter, and a level converter for inputting and outputting to the codec that converts digital signals to analog signals and vice versa. Input/output switching means for switching between the conversion unit or handset, output switching unit for switching the output of the tone generation unit between the level conversion unit or the transmitter, and a changeover switch for instructing switching between the input switching unit, the input/output switching unit, and the output switching unit. By absorbing the difference in the line selection signal system between digital and analog public telephones in the selection signal reception analysis section, it has the ability to send out PB signals from the transmitter that was available in analog public telephones. Auto-dial using an auto-dial device becomes possible. In addition, by switching the tone generation section and selection signal reception analysis section that are originally included in a digital public telephone by a switching section, and via a level conversion section, it is possible to make a call from an existing analog terminal. Existing analog terminals include, for example, portable facsimiles and portable computers with modems, which can be connected to these digital public telephones and use their auto-dial functions to make calls and communicate. The benefits are great. Furthermore, since only the billing-related portion is performed using a digital public telephone, there is the advantage that existing analog terminals can be used without modification. Furthermore, in the current situation, there are far more existing analog interfaces than digital interfaces in terms of the number of lines, so even if you make a call from a digital interface, in most cases the other party is using an analog interface, and it is difficult to communicate data using a PC, etc. Even if this is done, modems for analog interfaces are widespread, so it has the advantage of being able to use existing terminal resources as is.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention.
FIG. 2 is a block diagram showing the configuration of an example of a conventional terminal plaza. In the figure, 1 is a microprocessor, 2 is a program storage memory, 3 is a working memory, 4 is a digital signal control unit,
5 is a driver/receiver, 6 is a codec, 7 is a selection signal reception analysis section, 8 is a tone generation section, 9 is a switching section, 9a
9b is an input/output switching means, 9C is an output switching means, and 20 is a connection detection sensor.

Claims (1)

[Claims] In a digital public telephone that has a digital interface that transmits and receives telephone calls and subscriber line signals to and from the central office equipment as digital signals, a selection signal reception analysis unit that receives and analyzes a line selection signal of an analog interface, and a subscriber line signal for the analog interface. a level conversion unit that converts the signal to a predetermined level and transmits and receives the signal; an input switching unit that switches the input to the selected signal reception analysis unit with the level conversion unit or the transmitter; and converts a digital signal into an analog signal and vice versa. Input/output switching means for switching the input/output to the codec for conversion between the level converter or the handset, output switching means for switching the output of the tone generating section between the level converter or the handset, and the input/output switching means. A digital public telephone characterized by having a changeover switch for instructing switching of a switching means and an output switching means.