RU2132572C1 - User set - Google Patents

Abstract

FIELD: telephone equipment, guarding systems, telemetry and remote information transmission using data transmission through allocated telephone lines. SUBSTANCE: device has interface unit, user line, unit of filter, signal generator, voltage stabilizer, capacitance storage battery, controlled current clipper, voltage clipper, threshold circuit, current detector, pulse generator, power supply line for signal generator. Goal of invention is achieved by controlled voltage clipper, in order to improve quality of call signal generation. Device is supplied from user line. Telephone set provides pulse call method. EFFECT: possibility to transmit high-frequency information signal to user line in all operation modes, possibility of operations at user lines with increased wire resistance. 2 cl, 2 dwg

Description

 The proposed device relates to the field of radio engineering, in particular to telephone communications, combined with security systems, and is intended for use in security alarm systems and remote monitoring and control with the transmission of information on busy subscriber telephone lines.

 Known object alarm devices designed to transmit information on busy telephone lines (1, 2, 3) using a high-frequency signal (for example, at a frequency of 18 kHz). Such devices contain a power source from the 220 V network, a signal conditioning unit, the output of which through the galvanic isolation unit is connected to the subscriber line and a filter unit connected between the subscriber line and the telephone. The main disadvantage of such devices is the low reliability of the alarm system, due to their power supply from the 220 V network, which requires the use of redundant power sources in the event of a power failure in the 220 V.

 Known object devices whose power is supplied from a subscriber line (4, 5). Such devices contain a rectification bridge circuit connected to the subscriber line wires, the output of which is connected via a controlled current limiter (5) or voltage converter (4) to a capacitive storage device, the output of which is connected to the power bus of the signal conditioning unit (5).

 A disadvantage of the known devices is a violation of their power supply during prolonged shorting of the subscriber line by the telephone (when turning the dial of a dialer, or when dialing a pulse method), which is unacceptable in burglar alarm devices, because this leads to a false alarm. In addition, when charging capacitive storage devices (after they are deeply discharged when dialing or in talk mode), a failure may occur when dialing a telephone with a pulse method, because when the telephone line is opened, the current consumed from it increases sharply. For these reasons, it is not possible to use well-known power supply circuits for burglar alarm devices from a subscriber line in conjunction with a telephone with pulse dialing.

 Closest to the proposed device, both for its intended purpose and for the combination of essential features, is the Atlas-3 M object security alarm device described in (1), which is taken as a prototype.

 The prototype device (Fig. 2) contains a matching unit 1, the outputs of which are connected to the first 2 and second 3 wires of the subscriber line, a signal generating unit 4, the input of which is the input of the device, and its power bus 13 is connected to the output of the voltage stabilizer 11, the input which through a capacitive storage 9 is connected to the output of a transformer 14, which, in turn, is connected to a 220 V power supply network, and the subscriber line wires 2 and 3 are connected to the telephone through the filter unit 12.

 The device works - the prototype as follows. The network voltage "220" V is lowered by a transformer 14, rectified and filtered by a capacitive storage 9. The constant voltage of the capacitive storage 9 is stabilized by a voltage stabilizer 11, which is supplied to the power bus 12 of the signal generating unit 4. At the input of the signal generating unit 4, a control signal is supplied from an external controlled device. If there is a “Normal” signal at the input of block 4, it generates a sinusoidal voltage of 18 kHz at its output. This voltage is transformed by the matching unit 1 and fed through the isolation capacitor, which is part of the matching unit 1, to the subscriber line through which it is transmitted to the receiving equipment located at the telephone exchange. The subscriber's telephone is connected to wires 2 and 3 of the subscriber line through the filter unit 12. The filter unit 12 is tuned to a frequency of 18 kHz and decouples the subscriber line from the telephone at the frequency of the information signal (18 kHz) without introducing attenuation in the audio frequency range, therefore the input impedance of the telephone (which can be several tens of ohms in the dialing mode) does not affects the level of the information signal. Due to this, the device provides signal transmission at a frequency of 18 kHz when using the telephone ("on a busy telephone line").

 Upon receipt of an alarm notification signal generation unit 4 (alarm signal), the signal generating unit 4 stops generating a signal with a frequency of 18 kHz, which is recorded by the receiving equipment at the telephone exchange. It should be noted the importance of generating an information signal (18 kHz) in the “Normal” state, and not “Alarm”, because in this case the subscriber line breakage will also be registered as the “Alarm” mode, and not the “Normal” mode. Thus, the power consumption of the device in the "Normal" mode is the largest.

 In the event of a power failure in the 220 V power supply network, the device stops its operation (gives a false alarm). Since interruptions in power supply are possible under real operating conditions, the use of such a device is possible only if there is a backup power supply, for example, a battery connected to the power supply circuit of the device in the absence of a voltage of 220 V, which complicates the device. In addition, the use of such a device is impossible at sites without a power supply network, which limits its scope.

 The technical problem to which the invention is directed is to ensure the transmission of an informational high-frequency signal to a subscriber line when powered by a subscriber line in all operating modes connected to this line of a telephone with pulse dialing: waiting for a call, talking mode and dialing mode. An additional task is the ability to use the device on subscriber lines with increased wire resistance.

 This problem is solved in that an object device containing a matching unit, the first output of which is connected to the first wire of the subscriber line and the first input of the filter unit, and the second output - to the second wire of the subscriber line, is a signal conditioning unit whose output is connected to the input of the matching unit and the input is the input of the device, and the power bus of the signal conditioning unit is connected to the output of the voltage regulator, the input of which is connected to the output of the capacitive storage, a pulse shaper and control are introduced a current limiter, the inputs of which are connected to the first wire of the subscriber line, a current sensor, the input of which is connected to the output of the controlled current limiter, and the output to the input of the capacitive storage, a voltage limiter connected between the second input of the filter unit and the second wire of the subscriber line, and the stabilizer voltage is pulsed, and the control input of the current limiter is connected to the output of the pulse shaper and the output of the threshold circuit, the inputs of which are connected to the signal outputs of the current sensor.

 The voltage limiter is made controllable, and its control input is connected to the first wire of the subscriber line.

The invention is illustrated by drawings, where
FIG. 1 is a diagram of the proposed device;
FIG. 2 is a diagram of a prototype.

 The object device contains a matching unit 1, the first output of which is connected to the first wire 2 of the subscriber line, and the second output is connected to the second wire 3 of the subscriber line, a signal generating unit 4, the input of which is the input of the device, and the output is connected to the input of the matching unit 1, shaper 5 pulses and a controlled current limiter 6, the inputs of which are connected to the first wire 2 of the subscriber line, and the output of the 5 pulse shaper is connected to the control input of the controlled current limiter 6, current sensor 7, threshold circuit at 8, the output of which is connected to the control input of the controlled current limiter 6, the output of which is connected to the input of the current sensor 7, the signal outputs of which are connected to the inputs of the threshold circuit 8, capacitive storage 9, voltage limiter 10, switching voltage regulator 11 and filter unit 12, the outputs of which are connected to the inputs of the telephone (not shown in the diagram), and the first input to the first wire 2 of the subscriber line, and the second input to the output of the voltage limiter 10, the input of which is connected to the second wire 3 of the subscriber line SRI, the storage capacitor is connected to the input 9 of the current output of the sensor 7 and the output of the capacitive storage 9 - to the input of the switching regulator 11, the voltage output of which is connected to the bus 13, power supply unit 4 of the signal.

 In accordance with paragraph 2 of the formula, the voltage limiter 10 is made controllable, and its control input is connected to the first wire 2 of the subscriber line.

 Block 1 coordination is designed to coordinate the output of block 4 of the formation of the signal with the subscriber line. It provides galvanic isolation of the high-frequency signal and its transformation to the required level. In the simplest case, it is based on a transformer and an isolation capacitor.

 The signal generating unit 4 is intended for generating an information signal, the frequency of which, as a rule, lies above the range of sound frequencies (for example, 18 kHz) depending on the input signal. For example, in the Atlas-3 notification transmission system, if there is a Norm signal at the input of block 4, it generates a voltage of 18 kHz, and if there is an Alarm signal, a voltage of 18 kHz is not generated. In the Atlas-6 notification transmission system, the input signal changes the frequency of phase-shift keying of the signal to 18 kHz. It is made, for example, based on a crystal oscillator and an amplitude or phase modulator. The power supply of the signal generating unit 4 is carried out by the output voltage of the pulse voltage regulator 11 supplied via the power bus 13 (relative to the common bus of the device). In the particular case, with the indicated implementation of the device blocks (see Fig. 1), the second wire of the subscriber line is simultaneously a common bus of the device.

 The pulse shaper 5 generates a low-level signal lasting from 0.1 to 0.3 s with a positive voltage drop at its input, when the subscriber line is disconnected by the telephone when dialing a number using a pulse method. The pulse shaper 5 is made, for example, on the basis of a differentiating circuit and a key on a transistor.

 Managed current limiter 6 is designed to limit the current in the power circuit of the elements of the device from the subscriber line. So, when a low-level voltage pulse is generated at the output of the shaper 5, the controlled current limiter 6 closes and the current does not flow from its input to the output (this is necessary to minimize the current consumption of the device when opening the telephone line when dialing by pulse method). In addition, the controlled current limiter 6 provides a limitation of the current flowing through the current sensor 7 at a predetermined level. The controlled current limiter 6 is made, for example, based on a bipolar or field-effect transistor, the base of which (gate) is the control input of the limiter 6.

 The current sensor 7 is made, for example, based on a resistive current sensor. The voltage at the terminals of the resistor is proportional to the current flowing through it. The voltage from the signal outputs of the current sensor 7 is supplied to the inputs of the threshold circuit 8.

 The threshold circuit 8 is designed to control the current limiter 6 when increasing the current flowing through the current sensor 7, above the set value. In the simplest case, the threshold circuit 8 is based on a bipolar transistor and a diode - the cutoff voltage of the base junction and the diode determines the threshold of the threshold circuit 8. When increasing the current flowing through the current sensor 7 above the set limit (5-10 mA), the threshold circuit 8 affects the control input of the current limiter 6 provides a limitation of the current consumed from the subscriber line at a set level, which is necessary to prevent "capture" of the subscriber line during transients. Capacitive storage 9 serves to accumulate electrical energy consumed from the subscriber line, and power the elements of the device when the controlled current limiter 6 is turned off (when dialing by pulse method, etc.).

 Capacitive storage 9 is made, for example, on the basis of a capacitor and a diode connected at its input. The diode eliminates the discharge of the capacitor to the input circuit of the device.

 The voltage limiter 10 serves to fix the minimum voltage on the wires 2 and 3 of the subscriber line (about 9 V) when the output of the filter unit 13 is closed by the telephone, for example, when dialing a number. It is necessary to provide power to the device when the output of the filter unit 13 is closed. In the simplest case, the voltage limiter 10 is a zener diode.

 If the voltage limiter 10 is controlled according to claim 2, to fix the minimum voltage on the subscriber line, regardless of the resistance of the telephone set at the output of the filter unit 12, it is made, for example, based on a transistor with a zener diode in its base circuit determining a threshold voltage limits.

 The pulse voltage stabilizer 11 is designed to convert the voltage of the capacitive storage (40 - 60 V) into a low voltage (5 V), which is necessary to power the signal generating unit 4. The necessary quality of the stabilizer 11 is a high efficiency, which reduces the current consumed by it from the capacitive storage 9. A pulse stabilizer 11 is made according to known schemes and contains, for example, a key transistor, an LC low-pass filter and a pulse-width modulator (PWM).

 Block 12 of the filter is designed to decouple the high-frequency signal generated in the subscriber line, at the output of the matching unit 1, from the telephone, which eliminates both shunting of this signal by the telephone and penetration of a high-frequency signal at its input.

 The proposed device operates as follows. In standby mode, the connection circuit of the TA telephone (filter unit 12 output) is open and a voltage of about 60 V is present on wires 2 and 3 of the subscriber line. In this case, the capacitor of the capacitive storage 9 is charged through a controlled current limiter 6 and a current sensor 7. Moreover, the charge current is limited (at a level of 5 to 10 mA), due to the fact that when the current flowing through the current sensor 7 is exceeded, the voltage at the output of the current sensor 7 reaches the threshold of the threshold circuit 8, which affects its control signal to the control input limiter 6 current. By limiting the amount of current consumed from the subscriber line, preventing its "capture" (occupation of the line). The constant voltage of the capacitive storage 9 is supplied to the input of a pulse voltage stabilizer 11, which lowers (to a level of about 5 V) and stabilizes the voltage that provides power to the signal generating unit 4. Due to the fact that the voltage regulator is pulsed, with pulse-width modulation, it provides a voltage reduction with simultaneous transformation and the magnitude of the current consumption, which minimizes the current consumption from the subscriber line. So, when converting a voltage of 60 V to a voltage of 5 V, the input current of the pulse voltage stabilizer 11 is almost 10 times lower than its output current. Block 4 of the signal formation in the presence of a signal of a certain level of "Norm" at its input generates a high-frequency signal (for example, a frequency of 18 kHz) that lies above the sound frequency range. This signal is transmitted to the subscriber line through the block 1 matching, ensuring coordination of the output resistance of the block 4 of the formation of the signal with the subscriber line. The filter unit 12 prevents penetration of the output information signal of the signal generating unit 4 into the telephone and ensures that the input resistance of the telephone does not affect the information signal.

 When a voltage level of "Alarm" occurs at the input of the signal generation unit 4, the signal generating unit 4 either stops the formation of a high-frequency signal (in the Atlas-3 notification transmission system) or changes the nature of this signal (for example, changes the frequency of phase manipulation of a high-frequency signal in the transmission system Atlas-6 notices). This notice is received by a special device at the telephone exchange and transmitted to the central monitoring console.

 In the circuit closure mode of connecting the telephone (when turning the dial of the telephone), the output of the filter unit 12 is shorted and there is no voltage on the telephone. In this mode, the power of the elements of the proposed device is carried out from the subscriber line (wires 2 and 3) due to the inclusion in the connection circuit of the second wire 3 of the subscriber line with the input of the filter block 12 of the voltage limiter 10, which provides the specified voltage on wires 2 and 3 of the subscriber line (about 9 V ) necessary for the operation of the device. In colloquial mode, when the voltage drop on the telephone is from 10 to 20 V, the voltage on the wires of the subscriber line is sufficient to power the elements of the device without voltage limiter 10. Therefore, to prevent an additional increase in voltage on the wires of the subscriber line due to the voltage on the voltage limiter 10, in accordance with paragraph 2 of the formula, it is made controllable. In this case, if there is a voltage drop on the telephone, the voltage limit value of the limiter 10 is reduced so that the total voltage drop on the telephone and the voltage limiter 10 is maintained at a predetermined level. And when the voltage on the telephone set exceeds the initial voltage of the limiter 10 limit, it opens and the voltage drop on the wires 2 and 3 of the subscriber line practically coincides with the voltage drop on the telephone set, as a result of which the voltage limiter 10 does not affect the quality of telephone communication in the telephone circuit of the telephone set.

 In the pulse dialing mode, the proposed device provides minimal current consumption (less than 300 μA) when the telephone line is broken by the telephone (for a period of 50 to 100 ms, it is formed by the telephone dialer). This requirement is provided using a pulse shaper 5, which controls the operation of the controlled current limiter 6. So, when the connection circuit of the telephone set is broken (during the operation of the telephone dialer), the voltage on wires 2 and 3 of the subscriber line rises sharply. This voltage surge triggers a 5-pulse shaper, which generates a low-level voltage pulse lasting about 100 ms or until the voltage on the subscriber line decreases (when the telephone circuit is closed by its dialer). This low level voltage is supplied to the control input of the controlled current limiter 6 and locks it. As a result, the current consumption from the subscriber line when the dialer opens the proposed device is practically absent, which ensures the required pulse dialing mode. During the on state of the controlled current limiter 6 (duration up to 100 ms), the power of the signal generating unit 4 is provided from the energy of the capacitive storage 9.

 Thus, the proposed device provides the transmission of the high-frequency information signal to the subscriber line during power supply from the subscriber line in all operating modes of the telephone set connected to the line with pulse dialing: waiting for a call, talking mode and dialing mode. The implementation of the voltage limiter 10 controlled increased the quality of the formation of the dialing signal, which allows the device to be used on subscriber lines with increased wire resistance.

Sources of information
1. Terminal object device "Atlas - 3M". Technical description and instruction manual. FMLI.425.634.000 TO (prototype).

 2. Alarm device "Atlas-U". Subscriber kit. Technical description and instruction manual. MD2.407.014 TO.

 3. German patent N 4211820, MKI5 H 04 M 11/06, publ. 18.11.93. A method of transmitting data over telephone lines.

 4. US patent N 5216707, MKI H 04 M 11/06, NCI 379-39, 06.08.91. The operation circuit of the cassette relay in a coin-operated telephone from energy received due to the voltage on the wires of the telephone line.

 5. US patent N 5278888, MKI H 04 M 11/06, NCI 379-39. Signaling device warning system, interconnected with a telephone line.

Claims (2)

 1. An object device containing a matching unit, the first output of which is connected to the first wire of the subscriber line and the first input of the filter unit, and the second output is connected to the second wire of the subscriber line, the signal conditioning unit, the output of which is connected to the input of the matching unit, and the input is the input device, the power supply bus of the signal conditioning unit is connected to the output of the voltage regulator, the input of which is connected to the output of the capacitive storage, characterized in that it is equipped with a pulse shaper and controlled a current limiter, the inputs of which are connected to the first wire of the subscriber line, a current sensor, the input of which is connected to the output of the controlled current limiter, and the output to the input of the capacitive storage, a voltage limiter connected between the second input of the filter unit and the second wire of the subscriber line, and the voltage regulator made pulse, and the control input of the controlled current limiter is connected to the output of the pulse shaper and the output of the threshold circuit, the inputs of which are connected to the signal outputs of the sensor ok.  2. The device according to p. 1, characterized in that the voltage limiter is made controllable, and its control input is connected to the first wire of the subscriber line.

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