JPH0213160A - Call signal detector - Google Patents

Abstract

PURPOSE:To detect various kinds of telephone call signals in an excellent way without being affected due to noise by allowing a measuring means to discriminate a prescribed time longer than the pulse width of noise fed between input terminals as a telephone call signal. CONSTITUTION:A rectifier means 21 rectifying a telephone call signal supplied between input terminals T1, T2 and a measuring means 24 binarizing a rectified output from the rectifier means 21 at a prescribed threshold value and measuring the time of the binarized pulse width are provided to the detector, and the measuring means 24 discriminates a prescribed time longer than the pulse width such as noise fed between the input terminals T1, T2 as a telephone call signal. Thus, even if a call signal with a different kind is fed to the input terminals T1, T2, the quantity of the time of the binarized pulse width is measured and when the measured time is a prescribed time or over, since it is detected as a call signal, various call signals are identified.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a telephone ringing signal detection device.

[Summary of the invention]

The present invention relates to a ring signal detection device for a telephone set, and includes a rectifying means for rectifying a telephone ring signal supplied between input terminals of a ring signal detection circuit, and a commutator 1'! t, the rectified output is binarized with a predetermined threshold value, and a measuring means is provided for measuring the time of the binarized pulse width, and the measuring means is configured to measure the pulse width of the noise supplied between the input terminals. By determining that a long fixed period of time is a telephone call signal, various types of telephone call signals can be detected satisfactorily without being affected by noise.

[Conventional technology]

Tone ringer calling type telephones detect the presence or absence of a calling signal from an exchange and drive other calling circuits. As such a calling signal detection device, Japanese Patent Application Laid-Open No. 56-7666
Publication No. 6 discloses a configuration that prevents dial impulses and calling signals from being confused. This configuration and operation will be explained with reference to FIGS. 5 to 7.

In Fig. 5, the telephone line ringing signal detection circuit input terminal 'rt, T2 receives the ringing signal (16Hz) shown in Fig. 6A.
, sine wave, minimum 45vrms)el and dial impulse (1tlPPS or 20PPS) as shown in Figure 1A.

Meter rate 33%, 48VP-P) e 2 etc. are applied. A series circuit of a differential circuit f1+ consisting of a capacitor (2) and a resistor (3) and a diode (4) or a differential circuit (1
When a call signal is supplied to the series circuit of 1 and the light emitting diode t''t51, a half-wave rectified current of the power indicated by the arrow flows, and a current 11 as shown in FIG. 6B flows through the differentiator circuit (1). When a dial impulse is supplied, a differential current flows as shown in Fig. 7B.The instantaneous maximum value of this differential current is larger than that of the ringing signal, and when looking at the time in which it exceeds level LS1', it is larger than that of the ringing signal. When a flat wave current flows through the light emitting diode (5), a voltage proportional to the magnitude of this current appears on the collector side of the light receiving transistor (6).

The collector of the light receiving transistor (6) is connected to the load 1 & resistor (7).
) to the power supply terminal 8 supplied with the desired voltage Vcc.
)It is connected to the. When a call signal is supplied to the connection point between the collector and the load resistor (7), a voltage waveform ec1 shown in FIG. 6C appears, and when a dial impulse is applied, a voltage waveform ec1 shown in FIG. 7C appears. , 602 appears. These voltage waveforms ecLecj are supplied to a waveform shaping circuit (9).

The waveform shaping circuit (9) has a threshold value LS+, and by taking a value below this threshold value, the voltage waveform ec1. Depending on the magnitude of eC2, the output of the waveform shaping circuit (9) is a relatively wide binary pulse train P1 as shown in Figure 6 in the case of a call signal, and as shown in Figure 7 in the case of a dial impulse. A thin pulse train P2 shown in FIG.

In order to detect whether it is a calling signal or a dial impulse, depending on the width of the pulse train, indicated by P1 or P2, the binarized pulse train P1 to P2 is converted into a voltage corresponding to the pulse width. For this purpose, a series circuit of a resistor (11) and a capacitor (12) and a diode (13) and a resistor (14) connected in parallel to the resistor (11) are used.
is supplied to an integrating circuit (10) consisting of a series circuit of. Therefore, the output of the integrating circuit (10) is as shown in Fig. 6E and Fig. 7E.
A voltage set t ee2 appears with a level corresponding to the integrated pulse width as shown in - these voltages eet
tee2 is a level determination circuit (1
5) and whose level is judged by the level judgment circuit (15). ef2 is output to the output glass ゛l゛〕. That is, when the calling signal is manually input, the output voltage ef+ of "1" in FIG. Therefore, since the output voltage ef2 of "0" is taken out to the output terminal T3, the calling signal can be identified.

[Problem to be solved by the invention]

According to the prior art described above, it is possible to distinguish between a dial impulse and a ringing signal, but it is possible to distinguish between a dial impulse and a ringing signal, but it is possible to distinguish between a dial impulse and a ringing signal, but it is possible to distinguish between a dial impulse and a ringing signal. There was a problem in that it was not possible to identify ringing signals that differed somewhat depending on the country.

The present invention has been made in view of the above-mentioned problems, and its object is to provide a calling signal detection device capable of identifying various types of calling signals.

[Means to solve the problem]

An example of the calling signal detecting device of the present invention is shown in FIG. 1, as shown in FIG. T
Rectifying means (2
1), and a measuring means (24) for binarizing the rectified output using the rectifying means (21) with a constant threshold value and measuring the time of the binarized pulse width, the measuring means (24) is the input terminal T1. A certain period of time longer than the pulse width of the noise or the like supplied during the second interval is determined to be a telephone call signal.

[Effect]

Even if different types of calling signals are supplied to the input terminal of the calling signal detecting device according to the calling (i) detection device of the present invention,
These calling signals are rectified and binarized, the magnitude of the binarized pulse width is measured over time, and if the measurement time is longer than a predetermined time,
Since this is designed to be detected as a calling signal, various calling signals can be identified.

〔Example〕

An embodiment of the calling signal detection device of the present invention will be described below with reference to FIGS. 1 to 4.

A varistor (16) for overvoltage protection and a diode C1 are connected between the telephone line input terminals 'rl and 'T'2 in FIG. )
, (1B), (19), and (20) are connected to a full-wave rectifier circuit (21) in a bridge configuration. A series circuit of a capacitor (2) and a resistor (3) is connected as necessary between the input terminal Tr and the connection point a of the diode (17) and (1B>) of the full-wave rectifier circuit (21).

The capacitor (2) and resistor (3) are necessary to comply with the standards of the terminal equipment, and do not necessarily need to be provided especially as a high-pass filter. The input terminal "I" 2 is connected to the connection point C of the diodes (19) and (20), and the connection point C of the diodes (17) and (19).
is connected to the cathode of the light emitting diode (5), and the connection point d of the diodes (1B) and (20) is connected to the anode of the light emitting diode (5). The light emitting diode (5) and the light receiving transistor (6) constitute a photocoupler. The collector of the light-receiving transistor (6) is connected to the 'd1 terminal terminal 1 supplied with a predetermined voltage Vcc, the emitter is grounded via a resistor (22), and the base receives light from the light-emitting diode (5). irradiated.

The connection point between the light-receiving transistor (6) and the resistor (22) is connected to the controller (24) and one end of the capacitor (23), and one end of the capacitor (23) is grounded.
A waveform distorted by a time constant determined by the values of (22) and the capacitor (23) is output to the controller (24).

The operation in the configuration shown in FIG. 1 will be explained with reference to the waveform diagrams in FIGS. 2 and 3 and the flowchart in FIG. 4. Figures 2A-F are waveform diagrams when a calling signal is supplied to the input terminal T1゜1゛t, and Figures 3A-1? is input terminal “1”
11 This shows a waveform diagram when a dial impulse or pulse noise is applied to 'l'2. Figure 1 shows the input terminal 'I'i, and Figure 2 A shows the input terminal '1'2. When a normal 16 Hz, several hundred vpp alternating current is supplied with a ringing signal e1 that is "on" for one second and "off" for two seconds, the capacitor (2) and resistor (3) are connected as shown in Fig. 2. A current 11 shown in B flows, and a calling signal e1 is generated by the full-wave rectifier circuit (2
1), and the full-wave rectified waveform ert is supplied to the light emitting diode (5) as shown in FIG. 2C.

On the other hand, a dial impulse e2 as shown in FIG. 3A is input to the input terminal T1. If it is added to T2, it will be differentiated by the capacitor (2) and resistor (3) etc. in Figure 1, and it will become B in Figure 3.
A differential current 12 shown in is obtained. This differential current 12 is also full-wave rectified by the full-wave rectifier circuit (21), and a full-wave rectified waveform er2 is supplied to the light emitting diode (5) as shown in FIG. 3C.

When a full-wave rectified current flows through the light emitting diode (5) in this way, a voltage corresponding to the magnitude appears on the collector side of the light receiving transistor (6). When the ringing signal el is applied to the input terminal 'l''1.T2, a wide voltage epl is obtained as shown in Fig. 2C, and when the dial impulse is applied to the input terminal T1.'l''2, As shown in the voltage waveform ep2 of fIA3, the pulse width is smaller than that of the calling signal. These voltage waveforms epl 1ep2 are connected to the resistor (
22) and a time constant circuit including a capacitor (23) and then supplied to the controller (24). Call signal 1
6h itself does not differ significantly from this value, so
It purifies the signal near 161iz, but it is "on" for 1 second, 2
The values of the resistor (22) and capacitor (23) are set so as to leave traces that are repeated at a duty ratio of "off" in seconds.When the values of the time constant circuit are determined in this way, when a call signal is input, The integral waveform eit is as shown in FIG. 2E, and the integral waveform ei2 when the dial impulse is manually generated is as shown in FIG. 3E.

A controller (24) including a microcomputer monitors this output waveform efttef2. The controller (24) sets a predetermined threshold LS2 for the integral output waveforms ettl e12, and
When i2 exceeds the threshold LS2, "11" is output.

Therefore, in the controller (24),
An output waveform egl 16g2 as shown in Figure F can be extracted.

Therefore, the controller (2) outputs “1” of these output waveforms.
The time periods t1 and t2 are measured and outputted to the output terminal T3.

FIG. 4 shows that after detecting a calling signal, dial impulse, noise, etc., the "1" period 1. ．． This is a ``1-chart'' for counting the time of second grade.

First, when a waveform of “1” period is detected, the first step S
The counter is reset as shown in T L, and it is determined whether the human input signal input to the controller (24) is "1" or not. In the state of No, which is not “1”, the seventh step S i”
If you press t, it will be assumed that there is no incoming call and the call will end. Y15 whose input is “1” in the second step S '1'
In state 3, proceed to the third step S 'I'J and
Start the 60 second timer and proceed to the next 4th step S.
Update the counter at T4 and proceed to the next ff15 step ST
Proceed to s.

In the fifth step STs, it is determined whether the counter has reached 6 or not, that is, if the state of "1" continues for 100 m/s, it is assumed that a calling signal has been received. If it is less than 100 m/s, the process returns to the second step ST2.

In general, the period t2 of l'' for dial impulses, noise, etc.
As shown in Figure 3F, it is extremely short and the time is l0
There are very few that have 0rn/s.

On the other hand, since the "1" period of a calling signal, which varies depending on each country, or a calling signal for an extension, lasts 100 m/s, most of the calling signals can be detected. The period during which this "1" continues, that is, the recognition width, should be selected to be smaller than the width of the "1" period of various call signals and larger than the width of noise or dial impulse, but is not limited to <100 m/s. .

Returning to FIG. 4, if the fifth step ST6 is YES, the process proceeds to the sixth step STe, where it is assumed that there is an incoming call, that is, the calling signal is recognized, and the process ends.

According to the configuration of this example, ringing tones, which differ depending on the country or line model, can be distinguished from noise and dial impulses by detecting only signal periods longer than a certain time, making it simple and flexible. A ring signal detection device is obtained.

In other words, the present invention is not limited to the embodiments described above, and can be modified in various ways without departing from the gist of the present invention.

[Effects of the Invention] According to the calling signal detection device of the present invention, it is possible to detect calling signals that differ slightly depending on the country and specifications with a simple configuration without causing malfunctions due to noise, dial impulses, etc. It has the effect of obtaining something.

[Brief explanation of the drawing]

FIG. 3 is an explanatory diagram of the waveform when a dial impulse is supplied to the calling signal detection device of FIG. 5 is a circuit diagram of a conventional calling signal detection device, and FIGS. 6 and 7 are explanatory diagrams of waveforms when a calling signal and dial impulse are supplied to the calling signal detection device of FIG. 5. ( 4) is a light emitting diode, (6) is a light receiving transistor,
(9) is a waveform shaping circuit, (1,0) is an integrating circuit, (I5
) is the level judgment circuit, is the full-wave rectifier circuit, and is the controller. I ( Rinto Ito Teido Matsukuma Hidemori Book 4 ← August e14 'l-18j Input 衶nl 2nd figure Book v "uji File Input ζul Input Friend π Now this figure 3

Claims (1)

[Scope of Claims] Rectifying means for rectifying a telephone ringing signal supplied between input terminals of a ringing signal detection circuit; binarizing the rectified output by the rectifying means at a predetermined threshold; and measuring means for measuring the time of the pulse width of the noise pulse, and the measuring means is configured to determine that a certain period of time longer than the pulse width of the noise or the like supplied between the input terminals is a telephone call signal. A ring signal detection device.