KR20030035031A - Apparatus and method for detecting the phone's connection for analog subscriber card - Google Patents

Abstract

PURPOSE: An apparatus and a method for discriminating a connection of an analog telephone are provided to discriminate periodically the connection of the analog telephone by possessing a discriminating circuit within a subscriber unit. CONSTITUTION: An analog telephone connection discriminating unit(200) measures capacitance between lines. The analog telephone connection discriminating unit(200) comprises a ramp generator. The ramp generator applies a voltage being increased/decreased with a constant inclination to both ends of a connection line of an analog telephone. A current measuring device detects current according to the applied voltage. A capacitance calculator calculates capacitance of both ends of the line by using the values obtained from the ramp generator and the current measuring device and thus discriminates whether the analog telephone is connected or not.

Description

Apparatus and method for determining analog phone connection {APPARATUS AND METHOD FOR DETECTING THE PHONE'S CONNECTION FOR ANALOG SUBSCRIBER CARD}

The present invention relates to an exchange, and more particularly, to an apparatus and a method for determining whether an analog subscriber unit is connected to a telephone.

Typically, both digital and analog telephones can be connected to the exchange. However, in a general exchange, power is always applied to an analog subscriber unit, and thus power is consumed even in a line not used. That is, if power is not supplied to the unused line, power consumption may be reduced by reducing the power consumption. To this end, there is a need for a method that can determine a line that is not used, that is, an analog telephone is not connected.

Typically, the analog telephone connection can be determined by measuring the line capacitance between both ends of the TIP / RING.

On the other hand, conventionally, to determine whether the analog telephone connection had to use a separate equipment.

1 illustrates a conventional technology of determining whether an analog telephone is connected by using the separate equipment.

When the separate test equipment 120 is used as shown in FIG. 1, the track to be determined for the measurement is separated from the subscriber unit (subscriber board) 110, and then the measurement is performed through the test equipment 120.

As described above, when using the separate test equipment 12O, there is a problem that the telephone cannot be used during the measurement. In addition, since the exchange 100 does not know the information about the measurement, there is a problem that you must enter it manually.

An object of the present invention for solving the above problems is to provide an apparatus and method for determining whether the analog telephone is connected periodically by having a determination circuit in the subscriber unit.

The present invention for achieving the above object; A ramp generator that applies a voltage that is increased or decreased with a constant slope across an analog telephone connection line, a current meter that detects current according to the application of the voltage, and values measured from the ramp generator and the current meter An analog telephone connection determination device is used, characterized in that it is composed of a capacitance calculator for calculating capacitance and determining whether or not an analog telephone is connected.

1 is a diagram illustrating a conventional technology for determining whether an analog telephone is connected using the separate equipment.

2 is a diagram according to the present invention, which shows an exchanger capable of determining whether an analog telephone is connected without using a separate test equipment.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description of the reference numerals to the components of the drawings, it should be noted that the same reference numerals as much as possible even if displayed on different drawings.

In the following description, the device represented by the "subscriber board 110" in the drawings used in the present invention means a subscriber unit, and means an analog subscriber unit to which the present invention is applied.

FIG. 2 is a diagram according to the present invention, which illustrates an exchanger capable of determining whether an analog telephone is connected without using a separate test equipment.

The present invention will be described with reference to FIG. 2.

The subscriber board 110 of FIG. 2 is provided with an analog telephone connection determination unit 200.

The operation of determining whether the analog phone connection determination unit 200 is connected to the analog phone is as follows.

All analog phones have resistors and capacitors inside. In the present invention, the analog telephone connection determination unit 200 measures the capacitance between the lines to determine whether the analog telephone is connected. The analog telephone connection determiner 200 includes a ramp generator that increases and decreases a voltage at a constant slope, and measures a current component measured after applying a voltage at both ends of the line using a current meter. In the same manner as described above, the analog telephone connection determination unit 200 may measure capacitance required for determining whether the analog telephone is connected.

Therefore, in the present invention, a lamp generator and a current meter are used to determine whether an analog telephone is connected. Since the usage of the lamp generator and the current meter is easily understood by those skilled in the art, detailed descriptions of the circuit and the like will be omitted.

In the following description, for an easy understanding of the present invention will be described with one embodiment.

In the analog phone connection determination unit 200, a ramp generator is first connected to a line to which an analog phone is connected to increase or decrease the voltage with a constant slope. The current detected at this time is measured using a current meter. The capacitance calculator detects the capacitance between the both ends of the line using the measurement result and determines whether an analog telephone is connected. The result according to the measured value is illustrated below.

Initial value setting for measurement

Lamp generator initial voltage: 70V

Lamp Generator Termination Voltage: -30V

-Ramp generator tilt: 200V / s

-0V after lamp generation: 350ms

-Measured current integration time: 10ms

Current integration section: 345ms ~ 355ms

Measured current value: 1.96 mA

Capacitance across the measured line = 1.96 (mA) / 200 (v / S) = 9.8 uF

If the capacitance between the both ends of the line calculated using the measured values as described above is 9.8uF, it can be determined that the analog telephone is connected.

In this case, whether the analog phone is connected or not is determined by determining whether the measured capacitance falls within a range in which the analog phone is connected, and the determination range may be set by the user according to an experimental value.

In the present invention, since it is possible to determine whether the telephone is connected to the line through an internal circuit, there is an advantage that power consumption can be reduced by not applying power in the case of an unused line.

Claims (3)

An apparatus for determining whether an analog telephone is connected at an exchange, A ramp generator for applying a voltage that is increased or decreased with a constant slope across an analog telephone connection line, A current meter for detecting a current according to the application of the voltage; And a capacitance calculator that calculates capacitance across the line using values measured from the ramp generator and the current meter, and determines whether an analog telephone is connected. The method of claim 1, And determining whether the analog telephone connection is made by determining whether the calculated capacitance exists within a predetermined range that is recognized as being connected to the analog telephone. In the method of determining whether the analog telephone is connected in the exchange, Applying voltage to the analog telephone line at a constant slope; Measuring a current according to the voltage application; Measuring a capacitance value according to the voltage value and the current value; And determining whether or not the measured capacitance value is a value within a range that can be determined that the analog telephone is connected to the line.