JPH06121349A - Dial pulse detection method - Google Patents

Abstract

PURPOSE:To accurately control various electronic devices with equal perfor mance as a push type telephone set by detecting accurately a dial pulse of a dial pulse telephone set. CONSTITUTION:An HYB circuit 3 detecting a dial pulse signal sends a reception detection signal with an optional frequency and an optional waveform to a dial pulse telephone set at the transmission of the dial pulse signal. A change in a reflected wave at the dial signal transmission caused by short-circuit/ opening of a dial contact is detected by a pulse detection circuit 17. Since the dial pulse signal is detected in this way, the dial pulse is accurately detected.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dial pulse detecting method for a dial pulse type telephone, and more specifically, it is equivalent to a push type telephone by accurately detecting a dial pulse signal of the dial pulse type telephone. The present invention also relates to a dial pulse detection method capable of accurately controlling various electronic devices.

[0002]

2. Description of the Related Art Conventionally, in a dial type telephone, when a dial pulse is transmitted, a signal containing various harmonics is generated due to a transient phenomenon caused when the dial contact is disconnected, and only a signal within a communication band is generated. Is transmitted to the other party, and the dial pulse is detected by detecting the signal.

By the way, the dial of the telephone connected to the dial telephone line acts as a direct current dial pulse for the central office switch, but the direct dial pulse is sent to the other party via the central office switch. Transmission is basically impossible due to the structure of the central office.

Therefore, the dial pulse is detected as a signal containing a harmonic generated by a transient phenomenon when the dial contact is disconnected. That is, it can be said that the signal is an unstable signal because a considerable difference occurs depending on the disconnection state of the mechanical contact. This means that 100% detection of dial pulses is not possible as long as there is a telephone with mechanical contacts.

Further, in the current telephone line network, since the bandwidth of 300 Hz to 3400 Hz is transmitted satisfactorily, as long as the detection signal used between the telephones in the loop state uses the frequency within the transmission band, it is excellent. Signal transmission is expected. Therefore, as a detection signal, 1500H
If a sine wave of z is used, in FIG. 7, the make and break states of the dial Ds contact and Di contact are 1/1.
Can be detected with a delay of 500 seconds, 10 pp to 20
The detection of the pp dial pulse does not depend on the delay of 1/1500 seconds, and the operation of the dial DsDi contact is 1500 Hz.
It can be considered to detect a modulated wave that has been subjected to modulation.

[0006] Therefore, the present inventor has found the following as a result of various researches and studies based on this point. That is, a detection signal (sine wave) is momentarily sent from the detection device to the telephone in a call state (matching state) in a loop to detect the zero point, and a reflected wave from the telephone line including the telephone is transmitted. The reference signal generator detects the phase, amplitude,
A reference signal having the same frequency is created, 0 is output by comparing the reference signal and the reflected wave with a comparator, and a reference signal for setting the 0 point of the telephone line is formed. To create a reference signal with the same phase, amplitude, and frequency as the reflected wave from the matched telephone line.

The detection signal is 300 H in the audible wave band.
Since it is in the range of z to 3400 Hz, there is no problem in calling. Therefore, it cannot be always sent, and the harmonic dial pulse signal generated when the dial Ds contact at the time of dial pulse sending is used as a start signal for sending the detection signal, and if the dial Ds contact is made, a call is made. Since the circuit is shorted, there is no input to the handset,
Further, when the detection signal is transmitted at the same time, the reflected wave can be detected, and when the transmission of the dial pulse by the dial Di contact ends, the transmission of the detection signal is stopped, so that the reception signal sound cannot be heard by the handset.

When the zero point detection of the reflected wave of the telephone set (including the telephone line) in the talking state is completed, the detection device sends a detection signal to the dial Ds shunt contact,
A reflected wave is generated according to the operation of the dial Di impulse contact, and the operation of the dial Ds / Di contact (dial pulse) can be accurately detected by detecting the change in the reflected wave by the detection device. I clarified that.

The present invention has been made in consideration of the above points, and its purpose is to detect a dial pulse of a dial pulse type telephone accurately and to obtain a push type telephone. Equivalently, the object is to provide a dial pulse detection method that enables precise control of various electronic devices.

[0010]

A dial pulse detecting method of the present invention as means for achieving the above object is a dial pulse for detecting a dial pulse signal of a dial pulse type telephone in a call state. In the detection method, when the dial pulse signal is transmitted, a reception detection device of the dial pulse signal transmits a reception detection signal of an arbitrary frequency and an arbitrary waveform toward the dial pulse type telephone, and the dial pulse is transmitted when the dial pulse signal is transmitted. The dial pulse signal is detected by detecting a change in the reflected signal caused by short-circuiting / opening of the contact.

[0011]

According to the dial pulse detecting method of the present invention, since the telephone line (station switching HYB circuit) in a call state is matched with the internal impedance of the dial type telephone, the receiving side detecting device (station switching) in this state. Therefore, a sine wave with an arbitrary frequency is temporarily sent as a detection signal for zero point detection, the reflected wave at this time is detected, the phase and amplitude are stored, and the reflected wave in this state is detected as zero. It works so that the dial pulse can be detected.

That is, as for the dial contact at the time of sending the dial pulse, Ds (dial-shunt contact) first makes, and then Di (dial impulse contact) repeats intermittent connection. In this state, when viewed from the central office side (reception side detection device side), making of the Ds contact means short circuit of the line, and disconnection of Di contact means opening of the line. And
In this state, if the detection signal is sent from the detection device to the telephone, the internal impedance of the telephone changes from 0 to ∞ from the matching state of the call state. Therefore, the HYB circuit of the central office exchange has a reflectance of 100%. The reflected wave is generated and is transmitted to the detection signal transmission side by the reception circuit.

Therefore, by detecting the change of the reflected wave and shaping the waveform, the disconnection state of the dial contact can be accurately detected and can be reproduced as a DC dial pulse. The reflection when the internal impedance is 0 is ∞ due to the resistance of the telephone line to the telephone.
Less reflection than in the case of.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. Here, FIG. 1 to FIG.
1 shows an embodiment of the present invention, FIG. 1 is a block diagram of a dial pulse signal detection circuit, FIG. 2 is a block diagram of a HYB circuit,
3 to 5 are waveform diagrams when a 601 type dial telephone is used, FIG. 3 is an explanatory diagram of a reflected wave signal waveform at a position passing through a BPF, and FIG. 4 is an explanatory diagram of a detection waveform of a pulse length detection circuit. FIG. 5 is an explanatory diagram of the detection waveform at the detection level of the pulse length detection circuit.

The dial pulse detecting method of the present embodiment is roughly described. When a dial pulse signal is transmitted, a receiving detection device of the dial pulse signal directs a reception detection signal of an arbitrary frequency and an arbitrary waveform to the dial pulse type telephone. The dial pulse signal is detected by detecting the change in the reflected signal caused by the short-circuiting / opening of the dial contact at the time of sending the dial pulse.

The dial pulse detection method of this embodiment is specifically configured to detect the dial pulse signal using the dial pulse signal detection circuit shown in FIG. First, the device shown in FIGS. 1 and 2 will be described. In FIG. 1, reference numeral 1 is a loop detection circuit for detecting a loop of the terminal device, and if it is looped, the changeover switch 2 switches the telephone line through the detection device.

Reference numeral 3 denotes a detection-side HYB circuit configured as shown in FIG. 2, and the reflected wave of the detection signal transmitted from the transmitting side to the telephone line is received by the detection-side HYB circuit 3. Since it is output from the side, only the reflected wave of the detection signal is selected by the BPF 11, the phase adjustment circuit 13 in the phase detection circuit 14 is operated to generate the reference signal of the same phase, and then the amplitude adjustment circuit 15 is set. It is configured so that it can be operated to generate reference signals of the same phase, the same amplitude, and the same frequency.
This reference signal is held as the 0-point reference signal until the loop is released.

That is, the detection-side HYB circuit 3 makes its transmitting output the same as the station line circuit in the steady state in order to obtain an output close to 0 at the receiving circuit, and the output and the output of the station line circuit. By combining with F ₁ , the output can be brought close to 0, and a signal wave having the same phase and the same amplitude as the signal wave generated at the output F ₁ of the station line circuit can be generated by the output F _2. It can be configured.

The detection-side HYB circuit 3 can change the phase of the signal generated from the output F ₂ by changing the matching resistor ZR for phase detection and synchronization, and the sine wave output from F ₁ can be changed. Is shaped into a rectangular wave by a pulse shaping circuit after being amplified by an A ₂ amplifier,
It is possible to generate a short pulse at 0 °. In addition, the output F ₂ is processed in the same manner, and a signal point having the same phase as the F ₁ signal wave can be obtained by detecting the coincidence point of both pulses. In addition, the matching resistance ZR is automatically changed so that the NAND circuit detects a coincidence point of both pulses, and the automatic circuit is stopped at the same time when the coincidence point is detected.
Can be fixed and the phases can be synchronized. here,
The matching resistance ZR has a minimum of 600Ω and a maximum of 1000Ω changed in 64 steps.

The detection-side HYB circuit 3 detects the maximum values of the F ₁ and F ₂ signal waves and compares them if the signal waves of the same phase can be obtained. It can be regarded as a signal wave of amplitude, and the amplification degree of the F ₂ amplifier VA is a variable amplification circuit of 80 to 150, which is changed in 64 steps and is changed stepwise from the minimum amplification degree 80, and the maximum value is Change until they are the same. Then, when the maximum values become the same, the detection circuit stops the change of the amplification circuit and fixes the amplification degree. In this way, the operation output becomes an output close to 0 by adding the signal waves of the same phase and the same amplitude to the operation amplifier.

Reference numeral 6 denotes a 0-point detection circuit, which can be set after an arbitrary time of the loop. When the set time comes, the 0-point detection circuit 6 is sent from the detection signal sending circuit 7 through the signal switch 5 to B
_{From the} buffer 4 to the HYB circuit 3, the detection signal 150
The structure is such that a 0 Hz sine wave can be transmitted.

Here, the first dial pulse sent from the dial telephone to the detection device obliges the 0 dial input as the reference dial pulse. Specifically, the 0 dial pulse input by the dial pulse detection method of Japanese Patent Application No. 62-198859 is used to detect the input level of the signal and set the reference pulse length.

Next, the dial pulse detecting method of this embodiment using the dial pulse detecting device described above will be explained. First, when the first 0 dial pulse for reference is transmitted from the dial telephone, a dial pulse harmonic signal is generated, and the dial pulse harmonic signal is detected by the detection side H.
The signal is output from the receiving side of the YB circuit 3, passes through the LPF 9, and the level detection circuit 12 detects the input level and sets the level. At the same time, when the pulse detection circuit 17 detects an input pulse, the pulse detection circuit 17 acts as a start pulse of the detection signal and outputs the detection signal from the detection signal circuit 7 to B ₁
After passing through the buffer 4, the transmitting side of the detecting side HYB circuit 3 sends out to the telephone line.

The reflected wave of the detection signal is output from the receiving side of the HYB circuit 3 of the detection device. This reflected wave is phase-modulated by the HYB circuit of the central office switch, and is detected by the BPF 11 of the detection device. Only the reflected wave of the detection signal is selected, and the comparator 1 together with the reference signal created by the previous zero point detection is used.
At 8, the phase and amplitude are compared. And the output is BP
The signal waveform shown in FIG. 3 is selected by F19, and after the level is detected by the level detection circuit 20, the detection level of the reflected wave is set, and thereafter the detection level of the reflected wave is determined (see FIG. 4). At the same time, the pulse detection circuit 21 performs waveform shaping of the reflected wave as shown in FIG. 5, detects the dial pulse, and outputs the PB signal corresponding to the number of pulses and the pulse length from the DTMF transmission circuit 22. As expected. PB sent out
The signal is transmitted from the signal changeover switch 23 and the B ₂ buffer 29 to the terminal device through the detection device HYB circuit 26.

Next, when the reference dial pulse is input,
The input level of the dial pulse harmonic signal is set by the level detection circuit 12, and the input level of the reflection signal for detection is set by the level detection circuit 20. Here, since the input level detection with the reference 0 dial pulse is input of 10 pulses, the detection by averaging the input levels is accurate. Therefore, the input values of the dial pulse harmonic signal and the detection signal are set by the reference 0 dial pulse input. This dial pulse harmonic signal is
Since it is used as the start signal of the detection signal, it is necessary to set the detection level. At the same time, the pulse / pulse length detection circuit 21 detects the dial pulse and sets it as a reference dial pulse.

Here, the reference dial pulse is set by the distance of the telephone line or, depending on the system of the central office switch, the change of the internal resistance 0 or ∞ of the telephone at the time of sending the dial pulse is 100 in both phase and amplitude. %, The amount of reflection may be close to%, and the detection by the number of dial pulses cannot be accurately performed. In such a state, it becomes necessary to detect the dial pulse based on the dial pulse length.
As the dial pulse detection, it is desirable to detect the dial pulse by a detection method having both a detection method of the number of dial pulses and a detection method of the dial pulse length.

Therefore, according to the present embodiment, since the telephone line (local exchange HYB circuit) in the call state is matched with the internal impedance of the dial type telephone, in this state, the receiving side detection device is used for detection. A sine wave with an arbitrary frequency is temporarily sent as a signal for zero point detection, the reflected wave at this time is detected, the phase and amplitude are stored, and the reflected wave in this state is detected as 0 Can be detected.

It should be noted that the present invention is not limited to the above-described embodiments, but includes configurations that can be modified and implemented without departing from the scope of the present invention.

[0029]

As is apparent from the above description, according to the dial pulse detecting method of the present invention, when the dial pulse signal is transmitted, the receiving side detecting device for the dial pulse signal detects the reception of the arbitrary frequency and the arbitrary waveform. Since a signal is transmitted to the dial pulse type telephone and the change of the reflected signal caused by the short circuit / opening of the dial contact at the time of sending the dial pulse is detected, the dial pulse signal is detected. The dial pulse can be accurately detected, and the dial pulse detection method using the conventional dial pulse harmonic signal has a remarkable performance and the same signal transmission as that of the touch-tone telephone can be performed.

[Brief description of drawings]

FIG. 1 is a block diagram of a dial pulse signal detection circuit.

FIG. 2 is a block diagram of a HYB circuit.

FIG. 3 is a waveform diagram when a 601 type dial telephone is used, and is an explanatory diagram of a reflected wave signal waveform at a position after passing through a BPF.

FIG. 4 is an explanatory diagram of a detection waveform of a pulse length detection circuit.

FIG. 5 is an explanatory diagram of a detection waveform at a detection level of a pulse length detection circuit.

FIG. 6 is a schematic diagram of a 4-wire communication path.

7 is an equivalent circuit of the dial type telephone of FIG.

[Explanation of symbols]

1 ... Loop detection circuit, 2 ... Changeover switch, 3 ...
..HYB circuit, 4 ... B ₁ buffer, 5 ... changeover switch, 6 ... 0 point detection circuit, 7 ... detection signal sending circuit, 8 ... A ₂ buffer, 9 ...・ LP
F, 10 ... Loop control tone detection circuit, 11 ...
BPF, 12 ... Level detection circuit, 13 ... Phase adjustment circuit, 14 ... Phase adjustment circuit, 15 ... Amplitude detection circuit, 16 ... Amplitude adjustment circuit, 17 ... Pulse detection circuit, 18 ... comparator, 19 ... BPF, 20 ...
・ Level detection circuit, 21 ... Pulse length detection circuit, 22
... DTMF sending circuit, 23 ... Changeover switch, 2
4 ... B ₂ buffer, 25 ... A ₁ buffer,
26 ... HYB circuit

Claims (1)

[Claims] 1. A dial pulse detecting method for detecting a dial pulse signal of a dial pulse type telephone set in a call state, wherein at the time of transmitting the dial pulse signal, an arbitrary frequency is detected by a receiving side detecting device of the dial pulse signal, The dial pulse signal is detected by transmitting a reception detection signal of an arbitrary waveform to the dial pulse type telephone and detecting a change in the reflected signal caused by the short circuit or opening of the dial contact at the time of sending the dial pulse. A dial pulse detection method characterized by the above.