JP2002111606A - Transmission characteristic measuring device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a transmission characteristic measuring device which is capable of measuring the transmission characteristics of a communication line synchronous with event signals and improved in data analyzing function. SOLUTION: A transmission characteristic measuring device for measuring the transmission characteristics of a communication line that communicates high-speed digital data comprises a first and a second transmission characteristic measuring apparatus connected to the ends of a communication line as an object of measurement. The transmission characteristic measuring apparatuses are made to communicate by the use of the communication line as an object of measurement, the roles of the transmission-side transmission characteristic measurement apparatus which transmits reference signals to the communication line as an object of measurement and the receiving-side transmission characteristic measurement apparatus which receives reference signals and measures the transmission characteristics are set, and the transmission characteristic data measured by the receiving-side transmission characteristic measurement apparatus are transferred to the transmission-side transmission characteristic measurement apparatus through the communication line as an object of measurement.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for measuring transmission characteristics of a communication line such as a telephone line for communicating high-speed digital data, and more particularly to an apparatus for measuring transmission characteristics of a communication line synchronized with an event signal and analyzing data. The present invention relates to a transmission characteristic measuring device with improved functions.

[0002]

2. Description of the Related Art In conventional communication lines such as telephone lines, attenuation characteristics, noise characteristics, and TDR (Time Domain Reflectomete
r), characteristic impedance, noise path silverware, near-end crosstalk,
It measures transmission characteristics such as S / N ratio, communication line length, and balance. The transmission characteristics have been measured by supplying a signal from one end of a communication line under test, which is a device under test, and measuring the signal at the other end of the communication line under test.

[0003] In addition, measurement commands are transmitted and received between measuring instruments connected to both ends of a communication line to be measured, and measurement is performed while controlling the measuring instruments.

FIG. 19 is a configuration block diagram showing an example of such a conventional transmission characteristic measuring device. In FIG. 19, reference numerals 1 and 2 denote measuring instruments having a communication function and capable of outputting a reference signal, and 100 denotes a communication line to be measured as a device under test.

[0005] The measuring device 1 is connected to one end of a communication line 100 to be measured, and the other end of the communication line 100 to be measured is connected to a measuring device 2.

Now, the operation of the conventional example shown in FIG. 19 will be described. For example, when the measuring device 1 measures transmission characteristics as a local device, a command or the like is transmitted to the measuring device 2 which is a remote device via the communication line under measurement 100 to control the measuring device 2. , A reference signal or the like is output to the communication line under test 100.

[0007] The measuring device 1 is connected to the communication line 10 to be measured.
The reference signal propagating 0 is received and the transmission characteristics as described above are measured.

For example, when measuring the attenuation characteristic of the communication line under test 100, the measuring device 2 which is a remote device is controlled to sweep the frequency of the signal output to the communication line under test 100. On the other hand, the measuring device 1 which is a device on the local side takes in the signal propagated through the communication line 100 to be measured, obtains a spectrum, and displays it on a display means or the like, thereby obtaining an attenuation characteristic.

For example, when measuring the noise characteristic of the communication line under test 100, the measurement device 2 which is a remote device is controlled to stop the signal output from the communication line under test 100. On the other hand, the measuring device 1, which is a local device, obtains a noise signal input from the communication line under test 100, obtains a spectrum, and displays the spectrum on a display unit or the like, thereby obtaining noise characteristics.

As a result, measuring equipment is connected to both ends of the communication line under test 100, and while controlling each other's measuring equipment,
By transmitting a reference signal from one measuring device and receiving the reference signal from the other measuring device, it becomes possible to measure the transmission characteristics of the communication line to be measured.

FIG. 20 shows an example of a conventional transmission characteristic measuring apparatus having a multiplexer function for switching a communication line to a telephone station side and measuring transmission characteristics for a communication line selected by the multiplexer. FIG. 3 is a configuration block diagram.

In FIG. 20, 3 is a user's house, 4 is a main distributor, 5 is a line switch (Cross Connect), 6 is a signal separator (POTS Spilitter), and 7 is a multiplexer (DS).
LAM, Digital Subscriber Line Access Mulitiplex),
8 is a voice service device (Plain Old Telephone System S)
ervice: POTS Service), 9 is a network operation center (hereinafter, simply referred to as control device 9) which is a control device.

In FIG. 20, 100a is a communication line to be measured, 101 is a network, and 102 is an external IS.
XDS connected to P (Internet Service Provider)
It is a high-speed digital data signal such as L (Digital Subscriber Line). 4, 5, 6, 7 and 8 constitute a telephone office 50.

The communication line 100a from the user's house 3 is connected to the main distributor 4, a part of the output of the main distributor 4 is connected to the line switching device 5, and the rest is connected to the voice service device 8. The output of the line switching device 5 is connected to a signal separating device 6, the voice band signal is connected to a voice service device 8,
A high-speed digital data signal such as xDSL is connected to a multiplexer 7.

The control device 9 is connected to the multiplexer 7 and a test port in the line switching device 5 via the network 101, and the multiplexer 7 outputs a high-speed digital data signal 102 such as xDSL to an ISP or the like. .

Here, the operation of the conventional example shown in FIG.
1 will be described. FIG. 21 is a flowchart for explaining the operation of the conventional example. In "S001" in FIG. 21, the control device 9 notifies the line switching device 5 of information on the communication line to be measured 100a to be measured.

The line switching device 5 which has received the notification at "S002" in FIG. 21 disconnects the communication line under test 100a from the signal separation device 6, and connects to the test port at "S003" in FIG.

Then, in "S004" in FIG. 21, the test circuit in the line switching device 5 tests the communication line with the user's house 3. For example, a test start command is transmitted from the control device 9 to the circuit switching device 5, and the test circuit in the line switching device 5 tests the communication line. Alternatively, the test circuit in the line switching device 5 automatically tests the communication line after disconnecting the communication line.

In "S005" in FIG. 21, the test circuit in the line switching device 5 transmits the collected data to the network 1.
01 to the controller 9 and “S00” in FIG.
6 ", the circuit switching device 5
Is connected to the signal separating device 6 to return to the original state.

As a result, the telephone house 50 sends the user house 3
It is possible to measure the transmission characteristics of the communication line between the two.

[0021]

However, in the conventional example shown in FIG. 19, since the measuring instruments communicate with each other using the communication line 100 to be measured, if a problem occurs in the communication line to be measured, There was a problem that they could not cooperate with each other. In addition, there is a problem in that a switching process of the communication line to be measured occurs every time the measurement is performed, which requires a great deal of man-hours.

In the conventional example shown in FIG.
Measurement can only be performed from the side. In other words, there is a problem that only the measurement in the upward direction can be performed.

In addition, ISDN (Integrated
Services Digital Network) communication system is composed of three phases: uplink (transmission), pause, and downlink (reception), which are "1.0 seconds", "0.5 seconds" and "0.5 seconds", respectively.
This is performed at a fixed time of "1.0 seconds", and is synchronously transmitted throughout Japan.

Since such ISDN communication signals propagate together with xDSL communication signals of different communication systems in a gut in which 50 to 100 lines are collectively stored, mutual interference may occur in each communication. Although there is a possibility that the transmission characteristics may be affected, the conventional example shown in FIGS. 19 and 20 has a problem that the transmission characteristics of the communication line cannot be measured in synchronization with the ISDN signal.

Although it is possible to determine the length of a communication line using TDR, if there is a defect on the communication line or if the length of the communication line is long, signal attenuation will increase and the communication circuit There was a problem that it was difficult to find the length.

Furthermore, the analysis of the collected data is largely left to the user, and the measuring instrument has only a poor data analysis function, so that the cause of the failure cannot be comprehensively determined. there were. Therefore, an object of the present invention is to realize a transmission characteristic measuring apparatus capable of measuring transmission characteristics of a communication line synchronized with an event signal and having an improved data analysis function.

[0027]

In order to achieve the above object, according to a first aspect of the present invention, there is provided an apparatus for measuring transmission characteristics of a communication line for communicating high-speed digital data. A first and a second transmission characteristic measuring device connected to both ends of the communication line, and the first and second transmission characteristic measuring devices communicate using the communication line to be measured and transmit a reference signal to the communication line to be measured. Set the role of the transmission characteristic measuring device on the transmitting side to transmit to, and set the role of the transmission characteristic measuring device on the receiving side to receive the reference signal and measure the transmission characteristics, the said measured by the transmission characteristic measuring device on the receiving side By transferring the transmission characteristic data to the transmission-side transmission characteristic measuring device via the communication line to be measured, not only the measurement in the uplink direction but also the measurement in the downlink direction can be performed. In addition, centralized management of measurement data becomes possible.

According to a second aspect of the present invention, there is provided an apparatus for measuring transmission characteristics of a communication line for communicating high-speed digital data.
A first and a second transmission characteristic measuring device connected to both ends of the communication line to be measured, and a control device for storing and managing the measured transmission characteristic data, wherein the first and the second transmission characteristic measuring device are A transmission-side transmission characteristic measuring device that performs communication using the communication line to be measured and transmits a reference signal to the communication line to be measured, and a transmission-side transmission characteristic measuring device that receives the reference signal and measures transmission characteristics. By transferring the transmission characteristic data measured by the transmission characteristic measuring device on the receiving side to the control device via the communication line to be measured, not only the measurement in the uplink direction but also the downlink direction Can also be measured. In addition, centralized management of measurement data becomes possible.

According to a third aspect of the present invention, in the transmission characteristic measuring apparatus according to the first or second aspect, the transmission characteristic measuring device on the receiving side transfers the transmission characteristic data via a public line. , The collected measurement data can be transferred to a control device or the like regardless of the state of the communication line to be measured, and can be centrally managed by the control device or the like.

According to a fourth aspect of the present invention, in the transmission characteristic measuring apparatus according to the first or second aspect, the transmission characteristic measuring device on the receiving side transfers the transmission characteristic data using wireless communication. , The collected measurement data can be transferred to a control device or the like regardless of the state of the communication line to be measured, and can be centrally managed by the control device or the like.

According to a fifth aspect of the present invention, in the transmission characteristic measuring device according to the first or second aspect, the first or second transmission characteristic measuring device synchronizes with the input external input signal. By measuring the transmission characteristics, the transmission characteristics can be measured in synchronization with an event such as an external input signal.

According to a sixth aspect of the present invention, in the transmission characteristic measuring apparatus according to the first and second aspects, a trigger signal is detected from an external input signal input to the transmission characteristic measuring device on the transmitting side. Transmitting the trigger signal via the communication line to be measured to the transmission characteristic measuring instrument on the receiving side,
By measuring the transmission characteristics in synchronization with the trigger signal received by the transmission characteristic measuring device on the receiving side, it becomes possible to share an event signal between two or more transmission characteristic measuring devices.

According to a seventh aspect of the present invention, in the transmission characteristic measuring device according to the first or second aspect, the transmission characteristic measuring device short-circuits and opens the end point of the communication line to be measured. Switch means for selecting the output of the short-circuit opening means, communication means connected to the input / output of the switch means, an A / D converter connected to the output of the switch means and receiving an input signal; A D / A converter connected to an input of means for outputting the reference signal to the communication line to be measured, storage means for storing the acquired data and the data of the reference signal, and data acquired together for controlling the whole And the control means for calculating the transmission characteristics from above, it is possible to perform not only the measurement in the up direction but also the measurement in the down direction. In addition, centralized management of measurement data becomes possible.

According to an eighth aspect of the present invention, in the transmission characteristic measuring apparatus according to the seventh aspect, the control means includes:
By controlling the switch means to select the communication means, if there is no key operation, waits for reception of a command from the communication line to be measured, and if there is a key operation, is it possible to perform independent measurement? Judgment is performed, and if single measurement is possible, measurement processing is performed. If single measurement is not possible, a command is sent to the communication line to be measured and an instruction is given to another transmission characteristic measuring device connected to the end point. In addition, by performing the measurement process together with the transmission characteristic measurement device in the normal state, it waits for a command from the communication line to be measured, and can perform a necessary measurement process by receiving the command or operating the key.

According to a ninth aspect of the present invention, in the transmission characteristic measuring apparatus according to the seventh aspect, the control means includes:
Instruct the transmission characteristic measuring device on the receiving side to short-circuit the end point of the communication line to be measured, apply a small current to the communication line to be measured, measure the voltage generated in the communication line to be measured, and The resistance value can be measured by calculating the resistance value from the minute current flowing through the measurement communication line and the measured voltage value.

According to a tenth aspect of the present invention, in the transmission characteristic measuring apparatus according to the seventh aspect, the control means instructs a transmission characteristic measuring device on the receiving side to open an end point of the communication line to be measured. In addition, the capacity value can be measured by measuring the capacity of the communication line to be measured whose end point is opened.

According to an eleventh aspect of the present invention, in the transmission characteristic measuring device according to the seventh aspect of the present invention, there is provided a power supply control means for controlling supply of a power supply voltage to the main circuit, wherein the control means comprises the communication means. It is determined whether or not a specific pattern has been received, and when it has been received, the power supply control unit is controlled to supply a power supply voltage to the main circuit, and the communication unit receives a measurement end command, or is preset. After the lapse of the set time, the power supply control means is controlled to cut off the supply of the power supply voltage to the main circuit, thereby making it possible to reduce the power consumption of the transmission characteristic measuring device.

According to a twelfth aspect of the present invention, in the transmission characteristic measuring apparatus according to the seventh aspect, a trigger detecting means for detecting a trigger signal from an external input signal is provided, and the control means synchronizes with the trigger signal. By measuring the transmission characteristics, the transmission characteristics can be measured in synchronization with an event such as an external input signal.

According to a thirteenth aspect of the present invention, in the transmission characteristic measuring device according to the seventh aspect, the control means detects a trigger signal from an external input signal and starts synchronization via the communication line to be measured. A command is transmitted to another transmission characteristic measuring instrument connected to the other end, and a trigger signal is transmitted to the other transmission characteristic measuring instrument connected to the other end through the communication line to be measured. By transmitting a synchronization end command to the other transmission characteristic measuring device connected to the other end via a line, it becomes possible to share an event signal between two or more transmission characteristic measuring devices.

According to a fourteenth aspect of the present invention, in the transmission characteristic measuring apparatus according to the seventh aspect, the control means receives the synchronization start command, receives the trigger signal, and receives the trigger signal. By setting the cycle to the event timer while completing the setting of the event timer at the time of receiving the synchronization end command,
Event signals can be shared between two or more transmission characteristic measuring devices.

According to a fifteenth aspect of the present invention, in the transmission characteristic measuring apparatus according to the twelfth aspect, the trigger detecting means includes a variable voltage source, an output voltage of the variable voltage source, and the external input signal. A first comparator that is input, a counter circuit that counts the output of the first comparator, and a second comparator that outputs a trigger signal when the count value of the counter circuit matches a set value. And a set number control circuit that controls the value of the output voltage of the variable voltage source and outputs the set value, so that the event level can be set arbitrarily. Further, it becomes possible to output a trigger signal based on the number of occurrences of an event.

According to a sixteenth aspect of the present invention, in the transmission characteristic measuring apparatus according to the seventh aspect, the control means instructs a transmission characteristic measuring device on the receiving side to short-circuit an end point of the communication line to be measured. In this state, a pulse is output to the communication line to be measured, and the reflected pulse is measured. A pulse is output, the reflected pulse is measured, and the position of the reflection point is specified by synthesizing the observation waveforms in the end point short-circuit state and the end point open state, so that a faulty point exists on the communication line, As the length increases, the length of the communication circuit can be determined even if the signal attenuation increases.

According to a seventeenth aspect of the present invention, in the transmission characteristic measuring apparatus according to the seventh aspect, the control means instructs a transmission characteristic measuring device on the receiving side to short-circuit an end point of the communication line to be measured. Measure the resistance value of the communication line under measurement in the state, measured the capacitance value of the communication line under measurement in a state where the end point of the communication line under measurement is opened by instructing the transmission characteristic measuring device on the receiving side, A pulse is output to the communication line to be measured, the reflected pulse is measured, the position of the reflection point is specified, the distance to the end point of the communication line to be measured, the position of the branch point, the distance to the branch point and the branch. By calculating the distance of the communication line to be measured, the distance to the end point of the communication line to be measured, the position of the branch point, the distance to the branch point and the distance of the branched communication line by topology display on the display means, Worker is visually measured It is possible to obtain information of signal lines.

According to an eighteenth aspect of the present invention, in the transmission characteristic measuring apparatus according to the seventeenth aspect, the control means displays the end point of the communication line to be measured by a first straight line, and The communication line branching from the position of the branch point of the straight line is displayed as a second straight line obtained by branching, and the distance to the end point of the communication line to be measured is numerically displayed near the first straight line, By numerically displaying the distance of the communication line branching near the second straight line, and numerically displaying the distance to the branch point near the portion from the transmitting side to the branch point in the first straight line, The operator can visually obtain information on the communication line to be measured.

According to a nineteenth aspect of the present invention, in the transmission characteristic measuring apparatus according to the seventh aspect, the control means measures a voltage of the communication line to be measured, and the measured voltage is a dangerous voltage. Judgment is made as to whether or not the alarm voltage is exceeded, and if the dangerous voltage is exceeded, an alarm is generated and the measurement is waited for by the operator.If the measurement is approved, or the dangerous voltage is not exceeded By allowing the measurement of the communication line to be measured, security can be ensured.

[0046]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the drawings. FIG. 1 is a block diagram showing a configuration of a transmission characteristic measuring apparatus according to an embodiment of the present invention.

In FIG. 1, reference numerals 4 to 8, 101 and 102 denote the same reference numerals as in FIG. 20, 3a denotes a user house, 9
a is a control device, 10 and 11 are transmission characteristic measuring instruments, 12 is a personal computer (hereinafter simply referred to as a computer), and 13 is a PHS (Personal Handyphone System).
m) and a wireless communication device such as a mobile phone, and 14 is a receiving antenna such as a PHS or a mobile phone.

Further, reference numeral 100b denotes a communication line to be measured;
Reference numeral denotes a network such as a public line, and reference numeral 104 denotes an event signal relating to an ISDN signal. In addition, 4, 5, 6,
7, 8 and 10 constitute the telephone office 50a.

The communication line 100b connected to the measurement terminal of the transmission characteristic measuring device 11 installed in the user's house 3a is connected to the main distributor 4, and a part of the output of the main distributor 4 is connected to the line switching device 5. The rest is connected to the voice service device 8. The output of the line switching device 5 is connected to the signal separating device 6, the voice band signal is connected to the voice service device 8, and x
A high-speed digital data signal such as DSL is connected to a multiplexer 7.

The test port of the circuit switching device 5 (or the multiplexer 7) is connected to a measurement terminal of the transmission characteristic measuring device 10, and the event signal 104 is input to the transmission characteristic measuring device 10. The control device 9a is connected to the network 10
1 and connected to the multiplexer 7 and the transmission characteristic measuring device 10.
A high-speed digital data signal 102 such as DSL is output.

Further, the transmission characteristic measuring device 11 is connected to a computer 12, and the computer 12
03 is connected. A wireless communication device 13 is connected to the computer 12, and the wireless communication device 13
4 is connected to the network 103.

The operation of the embodiment shown in FIG. 1 will be described with reference to FIGS. FIG. 2 is a flowchart for explaining the operation at the time of measuring the transmission characteristics of the communication line to be measured, and FIG. 3 is a flowchart for explaining the operation at the time of transferring the collected data. However, description of the switching operation of the bad communication line to be measured, which is the same as the operation of FIG. 20 (FIG. 21), is omitted.

At the time of measuring the transmission characteristics, the transmission characteristic measuring devices 10 and 11 are connected to the communication line 1 to be measured at "S101" in FIG.
00b is used to set which transmission characteristic measuring instrument is on the remote side (transmitting side) and which transmission characteristic measuring instrument is on the local side (receiving side).

For example, the transmission characteristic measuring device 10 becomes a remote-side transmission characteristic measuring device, and the transmission characteristic measuring device 11 becomes a local-side transmission characteristic measuring device. The reverse pattern is also possible.

The transmission characteristic measuring device 10 on the remote side in "S102" in FIG. 2 transmits the reference signal to the communication line under test 100b, and the transmission characteristic measuring device 11 on the local side in "S103" in FIG. Communication line under test 100
The reference signal propagating through b is received and the transmission characteristics are measured.

As a result, the telephone office 50a and the user house 3
Since the transmission characteristic measuring device 10a and the transmission characteristic measuring device 11a may be set on the remote side and whichever is set on the local side, the measurement operation from the telephone station 50a side as in the conventional example shown in FIG. , Not only the measurement in the up direction,
Measurement work from the user house 3a, in other words, measurement in the down direction is also possible.

Further, in the above description, which transmission characteristic measuring device is to be the remote side or the local side is determined by performing communication or the like using the communication line under test 100b. Connected computer 12
Communication and the like may be performed with the transmission characteristic measuring device 10 using the network 103 connecting the control device 9a and the control device 9a.

Further, a wireless communication device 13 connected to the computer 12 is used to wirelessly connect to the network 103.
To communicate with the transmission characteristic measuring device 10.

In this case, unlike the conventional example shown in FIG. 19, it is possible to control the measurement even when a failure occurs in the communication line under test 100b.

On the other hand, at the time of data transfer, "S201" in FIG.
In, the transmission characteristic measuring device 11 on the local side determines whether or not the communication line under test 100b can communicate. If communication is possible, the transmission characteristic measuring device 11 transfers the data collected by using the communication line under test 100b to the transmission characteristic measuring device 10 on the remote side in "S202" in FIG. To the control device 9a. The control device 9a stores and manages the transferred data.

If the line 100b cannot communicate,
In the middle “S203”, the transmission characteristic measuring device 11 directly transfers the collected data to the control device 9a via the network 103 connected to the computer 12.

In some cases, in “S203” in FIG. 3, the transmission characteristic measuring device 11 uses the wireless communication device 13 connected to the computer 12 to wirelessly transmit the network 1
03 and transfers the collected data directly to the control device 9a.

As a result, the collected measurement data can be transferred to the control device 9a irrespective of the state of the communication line under test 100b, and can be centrally managed by the control device 9a.

FIG. 4 shows transmission characteristic measuring devices 10 and 11.
FIG. 3 is a configuration block diagram showing a specific example of FIG. In FIG.
Reference numeral 04 denotes the same reference numeral as in FIG. 1, reference numeral 15 denotes a short-circuit opening means for short-circuiting and opening one end of the communication line under test 100b,
Reference numeral 16 denotes switch means, 17 denotes communication means for performing communication using the communication line under test 100b such as a voice modem, and 18 denotes measurement means for measuring voltage, resistance, capacity, current, and the like.

In FIG. 4, reference numeral 19 denotes an A / D converter,
20 is a D / A converter, 21 is storage means for storing fetched data, 22 is storage means for storing output waveforms, 23
Is a control means for controlling the transmission characteristic measuring device, 24 is a trigger detecting means, 25 is a communication means such as various communication interfaces such as Ethernet, Bluetooth or RS-232C, 26 is a power supply, 27 is a driving means, and 28 is a switch circuit. It is.

Further, in FIG. 4, reference numeral 200 denotes a measuring terminal, and reference numerals 27 and 28 constitute a power supply control means 51.

The measuring terminal 200 is connected to the short-circuit opening means 15, and the output terminal of the short-circuit opening means 15 is connected to the switching means 16.
Connected to the input / output terminal of

The first output terminal of the switch means 16 is connected to the communication means 17, and the second output terminal of the switch means 16 is connected to the measuring means 18. Further, a third output terminal of the switch means 16 is connected to the A / D converter 19.

The outputs of the measuring means 18 and the A / D converter 19 are respectively connected to the storage means 21, and the output of the storage means 21 is connected to the control means 23. The input and output of the communication means 17 are mutually connected to the control means 23.

The output waveform data from the control means 23 is input to the storage means 22, and the output of the storage means 22 is connected to the D / A converter 20. The output of the control means 23 is connected to the communication means 25 and the driving means 27, and the D / A converter 2
The output of 0 is connected to the input terminal of the switch means 16.

The event signal 104 is connected to the trigger detecting means 24, and the trigger signal output from the trigger detecting means 24 is connected to the control means 23. The output of the driving means 27 is connected to a switch circuit 28,
Controls ON / OFF of the power supply voltage supplied from the power supply 26.

Further, the control means 23 controls the entire operation of the transmission characteristic measuring device, and the switch circuit 28 turns ON / OFF.
The controlled power supply voltage operates even in a command reception waiting state, and each component (hereinafter, referred to as a main circuit) other than the short-circuit opening means 15, the switch means 16, the communication means 17, the control means 23, and the power supply control means 51. Supplied to

Here, the operation of the transmission characteristic measuring device shown in FIG. 4 will be described with reference to FIGS. 5, 6, 7 and 8. 5 is a flowchart illustrating the operation of the transmission characteristic measuring device, FIG. 6 is a flowchart illustrating the operation of measuring the resistance value of the communication line under test, and FIG. 7 is a diagram illustrating the operation of measuring the capacitance value of the communication line under test. FIG. 8 is a flowchart illustrating the power control operation.

In step S301 in FIG.
Controls the switch means 16 to select the communication means 17. In "S302" in FIG. 5, the control means 23 determines whether or not a key (not shown) has been operated, and if no key has been operated, in "S303" in FIG. If a key operation has been performed while waiting for the reception of a command, it is determined in step S304 in FIG. 5 whether or not measurement can be performed by the transmission characteristic measuring device alone.

If a single measurement is possible, see FIG.
In step S305, the control unit 23 performs a measurement process. If independent measurement is not possible, in step S306 in FIG. 5, the control unit 23 transmits a command to the communication line to be measured and transmits other transmission characteristics connected to the end point. An instruction is given to the measuring device, and a measurement process is performed in "S307" in FIG.

On the other hand, in "S308" in FIG. 5, the control means 23 determines whether or not a command has been received from the communication line to be measured, and when the command has been received in "S309" in FIG. Execute the processing described in.

As a result, in the normal state, the transmission characteristic measuring device waits for reception of a command from the communication line to be measured, and can perform necessary measurement processing by receiving the command or operating the key.

Further, individual measurement processes will be described in detail. When measuring the internal resistance value of the measurement process,
In step S401 in FIG. 6, the transmission characteristic measuring instrument on the remote side short-circuits the end point of the communication line to be measured using the short-circuit opening means 15 in response to an instruction such as a command from the transmission characteristic measuring instrument on the local side.

In "S402" in FIG. 6, the local transmission characteristic measuring device applies a small current to the communication line to be measured and measures the voltage generated in the communication line to be measured in "S403" in FIG.

Then, in "S404" in FIG. 6, a resistance value is calculated from the minute current flowing through the communication line to be measured and the measured voltage value.

When measuring the internal capacity of the measurement process, the remote-side transmission characteristic measuring device is connected to the short-circuit opening means 15 by an instruction such as a command from the local-side transmission characteristic measuring device in "S501" in FIG. To open the end point of the communication line to be measured.

In "S502" in FIG. 7, the transmission characteristic measuring device on the local side measures the capacity of the communication line to be measured whose end point is open.

When a transmission characteristic measuring device is used in the field, it is necessary to save power because it is driven by a battery. The operation of such power saving will be described.

However, it is assumed that no power supply voltage is supplied to the main circuit in the initial state. For this reason, in such a state, the transmission characteristic measuring device cannot perform any operation other than the reception of the specific pattern or the detection of the key operation.

In step S601 in FIG.
Determines whether or not the communication unit 17 has received a specific pattern “ON pattern”, and if not, determines the presence or absence of a key operation in “S602” in FIG.

If there is no key operation in "S602" in FIG. 8, the control means 23 returns to the step of "S601" in FIG. 8, and if there is a key operation, and
When the “ON pattern” is received in the middle “S601”, the controller 23 controls the power controller 51 to supply the power voltage to the main circuit in “S603” in FIG.

In this state, since the power supply voltage is also supplied to the main circuit, it becomes possible to perform operations such as communication with other transmission characteristic measuring instruments and measurement processing.

Then, in "S604" in FIG. 8, the control means 23 determines whether or not a communication end command has been received by the communication means 17, and when the measurement end command has not been received, "in FIG. In S605 ", the control means 23 determines whether or not a preset time has elapsed.

If the set time has not elapsed in “S605” in FIG. 8, the process returns to the step of “S604” in FIG. 8, and if a command to end the measurement is received, and
When the set time has elapsed in the middle “S605”, the control unit 23 controls the power supply control unit 51 to cut off the supply of the power supply voltage to the main circuit in “S606” in FIG.

As a result, in a normal state, the supply of the power supply voltage to the main circuit is cut off, the power saving mode is set, and the power supply voltage is supplied to the main circuit by receiving an “ON pattern” or by operating a key, and the transmission characteristic measuring device is operated. By setting the mode to the normal operation mode and setting the power saving mode again after the reception of the measurement end command or the lapse of the set time, it becomes possible to reduce the power consumption of the transmission characteristic measuring device.

A case where the transmission characteristic of the communication line is measured in synchronization with an external input signal, for example, an ISDN signal by the transmission characteristic measuring device shown in FIG. 4 will be described with reference to FIGS. 9, 10 and 11. .

FIG. 9 is a timing chart showing the relationship between the ISDN signal and the measurement timing signal. FIG. 10 is a flow chart for explaining the operation of the transmission characteristic measuring device on the timing detection side.
FIG. 4 is a flowchart illustrating the operation of the transmission characteristic measuring device on the synchronization side.

As described in the conventional example, the transmission / reception signal of the ISDN is composed of three phases of uplink (transmission), pause, and downlink (reception) as shown in FIG. 0 seconds "," 0.5 seconds "and"
1.0 seconds ".

For this reason, as shown in FIGS. 9B and 9D, the control means 23 generates a measurement timing signal which has detected the rising and falling timings. The control unit 23 measures the transmission characteristics in synchronization with the ISDN phase in synchronization with the measurement timing signal.

For example, the rising of the up phase shown in FIG. 9A is detected, and “T001” and “T00” in FIG.
2 "is generated, and on the other hand, a rising timing of the downstream phase shown in FIG. 9A is detected and a measuring timing signal shown as" T003 "in FIG. 9 is generated.

Then, "T001" and "T00" in FIG.
In synchronization with “2”, the influence of the ISDN uplink signal indicated by “MS01” and “MS02” in FIG.
In synchronization with T003 ”, the influence of the downstream signal of ISDN is measured as indicated by“ MS03 ”in FIG.

Specifically, the above three phases correspond to the basic signals “64 kHz”, “8 kHz” and “0.4 kHz”.
Since these signals are controlled by the three signals z ″, these basic signals are taken into the transmission characteristic measuring device by the trigger detecting means 24 as the event signals 104 and the above-described measurement timing signals are generated and supplied to the control means 23. I do.

As a result, by acquiring the event signal 104 by the trigger detecting means 24 and generating a trigger signal, it becomes possible to measure the transmission characteristics in synchronization with an event such as an external input signal.

Further, in the description of FIG. 9, one transmission characteristic measuring device measures transmission characteristics in synchronization with an externally input event signal, but other transmission characteristics measuring devices connected to the other end of the communication line to be measured. It is possible to share the event signal with the characteristic measuring device.

The sharing operation will be described with reference to FIGS. 10 and 11. FIG. 10 is a flowchart for explaining the operation of the transmission characteristic measuring device to which the event signal is input, and FIG.
FIG. 8 is a flowchart for explaining the operation of another transmission characteristic measuring instrument receiving provision of event information.

At "S701" in FIG. 10, the transmission characteristic measuring device detects an event signal 1 such as an ISDN signal input from the outside.
From 04, a trigger signal is detected. Then, "S" in FIG.
At 702 ", the transmission characteristic measuring device transmits a synchronization start command to another transmission characteristic measuring device connected to the other end via the communication line to be measured.

Then, in "S703" in FIG. 10, the transmission characteristic measuring device transmits the detected trigger signal as an event signal to another transmission characteristic measuring device connected to the other end via the communication line to be measured. Finally, in "S704" in FIG. 10, the transmission characteristic measuring device transmits a synchronization end command to another transmission characteristic measuring device connected to the other end via the communication line to be measured.

On the other hand, the transmission characteristic measuring instrument connected to the other end of the communication line to be measured receives the synchronization start command in "S801" in FIG. 11, and receives the event signal in "S802" in FIG.

Then, in "S803" in FIG. 11, the transmission characteristic measuring instrument sets the cycle of the event timer while receiving the event signal. When the synchronization end command is received in "S804" in FIG. Complete the settings.

That is, the period of the event signal detected by one of the transmission characteristic measuring devices is notified to the other transmission characteristic measuring device, and the other transmission characteristic measuring device sets the period to the event timer, whereby two or more events are set. Event signals can be shared between the transmission characteristic measuring devices.

In the description of FIG. 9, an externally input event signal is detected as it is, but the event level can be set arbitrarily. FIG. 12 is a configuration block diagram showing a specific example of the trigger detection means 24 which enables such an arbitrary setting of the event level.

In FIG. 12, reference numeral 104 denotes the same reference numeral as in FIG. 4, reference numeral 29 denotes an analog signal comparator, reference numeral 30 denotes a variable voltage source, reference numeral 31 denotes a counter circuit, reference numeral 32 denotes a digital signal comparator, and reference numeral 33 denotes a control circuit. , 105 are trigger signals.

The event signal 104 is input to one input terminal of the comparator 29, and the other input terminal of the comparator 29 is connected to one terminal of the variable voltage source 30. Comparator 29
Is connected to the count circuit 31 and the counter circuit 3
The output of 1 is connected to one input terminal of the comparator 32.

The output signal of the control circuit 33 is connected to the other input terminal of the comparator 32.
5 is output. Further, a control signal of the control circuit 33 is connected to a control input terminal of the variable voltage source 30, and a reset signal of the control circuit 33 is connected to the counter circuit 31. further,
The other end of the variable voltage source 30 is grounded.

Here, the trigger detecting means 24 shown in FIG.
Will be described. The input event signal 104 is compared in the comparator 29 with the output voltage of the variable voltage source 30 as a threshold. If the event signal 104 is larger (or smaller) than the threshold, the output of the comparator 29 becomes, for example, a high level.

The counter circuit 31 sequentially counts the pulses of the comparator 29 and outputs a count result. The comparator 32 compares the count value with the set value applied from the control circuit 33, and outputs a trigger signal 105 when the count value reaches the set value.

On the other hand, the control circuit 33 controls the value of the output voltage of the variable voltage source 30 by the control signal, in other words,
Adjust the event level by adjusting the threshold.

As a result, the control circuit 33 causes the comparator 29
By adjusting the threshold value, the event level can be arbitrarily set. Further, by outputting the trigger signal when the output of the comparator 29 is counted and reaches the set value, it becomes possible to output the trigger signal based on the number of occurrences of the event.

Although the length of the communication line can be obtained by using the TDR, the length of the communication circuit can be determined even if there is a defect on the communication line or the communication line length becomes long. Can be obtained.

The operation for obtaining the length of the communication line will be described with reference to FIGS. 13, 14 and 15. FIG.
FIG. 14 is an explanatory diagram showing an example of a TDR when an end point of a communication line is short-circuited. FIG. 14 is a diagram showing a TD when an end point of the communication line is opened.
FIG. 15 is an explanatory diagram showing an example of R, and FIG. 15 is a characteristic curve diagram showing an example of the obtained waveform and the synthesized waveform.

In FIGS. 13 and 14, reference numerals 34 and 35 denote transmission characteristic measuring instruments, and reference numeral 100c denotes a communication line to be measured. The short-circuit opening means 15 of the transmission characteristic measuring device 35 short-circuits the end point of the communication line 100c to be measured as shown in "ST01" in FIG. 13, and transmits a pulse as shown in FIG. In this case, a reflected pulse as shown in FIG.

On the other hand, in the short-circuit opening means 15 of the transmission characteristic measuring device 35, the end point of the communication line 100c to be measured is
Open as shown in the middle “OT01” and set the transmission characteristic
When a pulse as shown in FIG. 14A is transmitted from FIG. 4, a reflected pulse as shown in FIG. 14B is returned.

As described above, the transmission / reception waveform from the transmission of the pulse to the acquisition of the reflected pulse is shown in FIGS. 15 (a) and 15 (b).
It becomes as shown in.

For example, when the end point of the communication line to be measured is short-circuited and the pulse indicated by “SP01” in FIG. 15 is transmitted, after the time indicated by “TM01” in FIG.
A reflected pulse as shown in “RP01” is observed.

Similarly, for example, when the end point of the communication line to be measured is released and the pulse indicated by “SP02” in FIG. 15 is transmitted, after the lapse of the time indicated by “TM02” in FIG. 15, “RP02” in FIG. A reflected pulse as shown in "" is observed.

At this time, since the distances to the transmission characteristic measuring device 35, which is the end point, are the same, "TM01" and "T
M02 "are the same, and the reflected pulses have opposite polarities.

Here, by synthesizing the observed waveforms of FIGS. 15A and 15B, a reflected pulse waveform as shown by “CRP” in FIG. 15 can be obtained, and “CRP” in FIG.
The waveform indicated by RP "is larger than one of the reflected pulses, so that the identification becomes easy.

As a result, unlike the conventional example, even if there is a defect on the communication line or if the signal attenuation increases as the communication line length increases, the end point of the communication line to be measured is short-circuited and open-ended. By combining the observed waveforms, the length of the communication circuit can be obtained.

Further, it is possible to graphically display the topology (connection information) of the information of the communication line to be measured by the resistance value, the capacitance and the TDR measured in this way. That is, if the resistance value and the capacitance value with respect to the length of the conductor of the communication line to be measured are set in the transmission characteristic measuring device in advance, the length of the communication line, the position of the branch point, and the like can be obtained.

Such a data analysis operation will be described with reference to FIGS. FIG. 16 is a flowchart showing the operation of the transmission characteristic measuring device, and FIG. 17 is an explanatory diagram showing an example of a topology display screen.

In "S901" in FIG. 16, one transmission characteristic measuring device controls the other transmission characteristic measuring device connected to the other end of the communication line to be measured to short-circuit the other end of the communication line to be measured. In step S902, the resistance value of the communication line to be measured is measured by the above-described procedure. For example, assume that the measured resistance value is “260 [ohm]”.

Further, in "S903" in FIG. 16, one transmission characteristic measuring device controls the other transmission characteristic measuring device connected to the other end of the communication line under test to open the other end of the communication line under measurement. At the same time, in "S904" in FIG. 16, the capacity value of the communication line to be measured is measured by the above-described procedure. For example, assume that the measured capacitance value is “0.07 [μF]”.

Further, in "S905" in FIG. 16, one transmission characteristic measuring device performs TDR of the communication line to be measured.
For example, it is assumed that the point of the change point of the impedance by TDR is a point of “0.5 km”.

Then, in "S906" in FIG. 16, one of the transmission characteristic measuring devices performs arithmetic processing to determine the distance to the end point of the communication line to be measured, the total distance of the communication line to be measured, the position of the branch point of the line, The distance and the like of the branched communication line are obtained.

For example, if the measured resistance value is “260 [o
hm], and the resistance value with respect to the length of the conductor is “130 [oh]
m / km] ”, the communication line to be measured is short-circuited at the end point and is in a loop, so the actual resistance value is“ 1 ”.
/ 2 ", and assuming that the distance of the communication line to be measured is" L1 ", L1 = (260/2) /130=1.0 [km] (1)

For example, when the measured capacitance value is “0.07
[ΜF] ”and the capacitance value with respect to the length of the conductive wire is“ 0.05 ”.
[ΜF / km] ”, assuming that the total line distance of the communication line to be measured is“ L2 ”, L2 = 007 / 0.05 = 1.4 [km] (2)

For example, the total line distance “L2” is “1.4”.
[Km] ”and the distance to the end point of the communication line to be measured”
Since L1 "is" 1.0 [km] ", the distance" L3 "of the communication line branched from the branch point is: L3 = 1.4-1.0 = 0.4 [km] (3) It is.

Finally, in "S907" in FIG. 16, one of the transmission characteristic measuring devices displays the obtained distance to the end point of the communication line to be measured, the total distance of the communication line to be measured, and the position of the branch point of the line. (Not shown).

For example, such a topology display is shown in FIG.
As shown in FIG. "TD01" and "TD" in FIG.
02 ", the distance to the end point of the communication line to be measured and the distance of the communication line branched from the branch point are relatively displayed.
The branch point indicated by “DP01” in FIG. 17 is specified.

For example, as shown by “LD01” and “LD02” in FIG. 17, the numerical values of the distances “L1” and “L3” are displayed, and the distance to the branch point “DP01” obtained by TDR. Are displayed as indicated by “LD03” in FIG.

Further, for example, “PD01” in FIG. 17 also displays parameters such as the measured resistance value, capacitance value, TDR, and the resistance value and capacitance value with respect to the length of the conductor set in advance.

As a result, the collected data is analyzed in the transmission characteristic measuring instrument, and the topology is displayed as shown in FIG. 17, so that the operator can visually obtain information on the communication line to be measured.

Finally, when measuring the transmission characteristics of the communication line to be measured, there is a possibility that the communication line to be measured is touched by hand. For this reason, the transmission characteristic measuring device can measure the voltage of the communication line to be measured in advance for safety and call attention to the worker.

Such a harm prevention operation will be described with reference to FIG. FIG. 18 is a flowchart illustrating the operation of the transmission characteristic measuring device. In "S1001" in FIG. 18, the control means 23 of the transmission characteristic measuring instrument measures the voltage of the communication line to be measured by the measuring means 18.

It is determined whether or not the voltage measured in “S1002” in FIG. 18 exceeds the dangerous voltage. If the dangerous voltage is exceeded, “S1” in FIG.
At 003 ", the control means 23 generates an alarm and waits for the operator to approve the measurement at" S1004 "in FIG.

For example, as the alarm, a warning screen can be displayed on a display means (not shown), or an alarm can be issued by a buzzer (not shown).

It is determined in step S1005 in FIG. 18 whether the measurement has been approved. If the measurement has not been approved, the process proceeds to step S1005 in FIG.
Return to step 1003 ". If the measurement is approved, or if the dangerous voltage is not exceeded in" S1002 "in FIG. 18," S1006 "in FIG.
In FIG. 5, the measurement of the communication line to be measured is permitted.
The procedure as shown in is performed.

As a result, it is checked in advance whether or not the voltage of the communication line under measurement is a dangerous voltage. If the voltage exceeds the dangerous voltage, an alarm is generated and the next step, in other words, the measurement is performed. By asking the operator whether to proceed to the operation, safety can be ensured.

In the description of the embodiment shown in FIG. 1, the transmission characteristic measuring device 11 and the computer 12 are connected by wire. However, in the case of measurement at the site, outdoor measurement, measurement under wind and rain, and under high temperature Poor environment such as measurement under high humidity is expected.

For this reason, it is not suitable to connect the transmission characteristic measuring device 11 and the computer 12 by wire, and
Wireless communication such as tooth may be used. In this case, the remote operation of the transmission characteristic measuring device 11 from the computer 12 becomes possible.

In the description of the embodiment shown in FIG. 1, the transmission characteristic measuring device 11 and the computer 12 are connected to each other, and the computer 12 is connected to the network 103. The transmission characteristic measuring device 11 may be directly connected to the network 103 because it has the communication means 25 as various communication interfaces such as Ethernet, Bluetooth or RS-232C as shown.

In the description of the transmission characteristic measuring device shown in FIG. 4, a public line or wireless communication is used when the communication line to be measured cannot communicate, but the communication line to be measured is in a communicable state. Of course, a public line or wireless communication may be used.

In the description of the transmission characteristic measuring device shown in FIG. 4, the storage means 21 and 22 are shown separately for the sake of simplicity. Of course, the address of one storage means is appropriately divided. It is possible to realize both functions.

In the description of the transmission characteristic measuring device shown in FIG. 4, a measuring means 18 is separately provided for simplicity of description, but a predetermined arithmetic processing is performed on the data taken in by the A / D converter 19. , The function of the measuring means 18 can be taken into the control means 23.

In the description related to FIG. 8, whether the power supply voltage is supplied to the main circuit is determined based on the presence or absence of the key operation. However, the power supply voltage is supplied to the main circuit only based on the reception of the specific pattern. You may decide whether or not to do so.

In the description regarding FIG.
Although only the effect on the up and down of the DN is measured, of course, the effect in the dormant state may be measured.

In the description of FIG. 16, the topology is displayed by the transmission characteristic measuring device on the local side (measuring side), but may be displayed by the transmission characteristic measuring device on the remote side (short circuit and open side). Alternatively, the collected data may be displayed on the control device 9a which centrally manages the collected data.

Although only the connection information of the communication line and various parameters are displayed on the topology display screen shown in FIG. 17, the communication service and the estimated communication speed that can be used based on the obtained line length, S / N ratio, etc. It is possible to display information that can be obtained by calculation from transmission characteristics such as.

[0154]

As is apparent from the above description,
According to the present invention, the following effects can be obtained. According to the first, second and seventh aspects of the present invention, two transmission characteristic measuring devices connected to both ends of the communication line to be measured perform communication using the communication line to be measured and the roles of the transmitting side and the receiving side. Setting not only allows measurement in the up direction but also measurement in the down direction. Further, by transferring the collected data using the communication line to be measured, it becomes possible to centrally manage the data by a control device or the like.

According to the third and fourth aspects of the present invention, the collected data is transferred by appropriately using a public line or wireless communication, so that the collected measurement data is related to the state of the communication line to be measured. And can be transferred to a control device or the like, and can be centrally managed by the control device or the like.

According to the fifth and twelfth aspects of the present invention, the transmission characteristics are measured in synchronization with the input external input signal, so that the transmission characteristics synchronized with an event such as an external input signal are obtained. Can be measured.

According to the present invention, a trigger signal is detected from an external input signal input to the transmission characteristic measuring device on the transmission side, and the trigger signal is detected by the transmission characteristic measuring device on the receiving side. By transmitting a trigger signal via the communication line to be measured and measuring the transmission characteristics in synchronization with the trigger signal received by the transmission characteristic measuring device on the receiving side, an event occurs between two or more transmission characteristic measuring devices. Signals can be shared.

According to the invention of claim 8, when there is no key operation, the reception of a command is waited, and when there is a key operation, a single measurement or a command is transmitted to the communication line to be measured, and the In the normal state, the transmission characteristic measurement device waits for a command from the communication line under measurement by giving instructions to other transmission characteristic measurement devices connected to the Measurement processing can be performed.

According to the ninth aspect of the present invention, the end point of the communication line to be measured is short-circuited, a voltage generated by flowing a minute current is measured, and a resistance value is determined from the minute current and the measured voltage value. By performing the calculation, the resistance value can be measured.

According to the tenth aspect of the present invention, the capacity value can be measured by opening the end point of the communication line to be measured and measuring the capacity of the communication line to be measured whose end point is opened.

According to the eleventh aspect of the present invention, the power supply control means for controlling the supply of the power supply voltage to the main circuit is provided. By supplying the power supply voltage and receiving a measurement end command, or when a preset time has elapsed, the power supply control means is controlled to cut off the supply of the power supply voltage to the main circuit, thereby measuring the transmission characteristics. It is possible to reduce the power consumption of the container.

According to the fifteenth aspect, the event level can be arbitrarily set by comparing the external input signal with the adjustable threshold value and counting the comparison result. Further, it becomes possible to output a trigger signal based on the number of occurrences of an event.

Further, according to the sixteenth aspect of the present invention, the position of the reflection point is specified by synthesizing the observation waveforms in the end point short-circuit state and the end point open state, so that a faulty point exists on the communication line. As the communication line length increases, the length of the communication circuit can be determined even if the signal attenuation increases.

According to the seventeenth and eighteenth aspects, the distance to the end point of the communication line to be measured, the position of the branch point, the distance to the branch point, and the distance of the branched communication line are calculated. By displaying the topology to the distance to the end point of the communication line to be measured, the position of the branch point, the distance to the branch point, and the distance of the branched communication line on the display means, the operator can visually recognize the communication line to be measured. Information can be obtained.

According to the nineteenth aspect of the present invention, it is checked in advance whether or not the voltage of the communication line to be measured is a dangerous voltage. If the voltage exceeds the dangerous voltage, an alarm is generated. In the next step, in other words, by asking the operator whether to proceed to the measurement operation, safety can be ensured.

[Brief description of the drawings]

FIG. 1 is a configuration block diagram showing an embodiment of a transmission characteristic measuring device according to the present invention.

FIG. 2 is a flowchart illustrating an operation at the time of measuring transmission characteristics of a communication line to be measured.

FIG. 3 is a flowchart illustrating an operation of transferring collected data.

FIG. 4 is a configuration block diagram showing a specific example of a transmission characteristic measuring device.

FIG. 5 is a flowchart illustrating the operation of the transmission characteristic measuring device.

FIG. 6 is a flowchart illustrating an operation of measuring a resistance value of a communication line to be measured.

FIG. 7 is a flowchart illustrating an operation of measuring a capacity value of a communication line to be measured.

FIG. 8 is a flowchart illustrating an operation of power supply control.

FIG. 9 is a timing chart showing a relationship between an ISDN signal and a measurement timing signal.

FIG. 10 is a flowchart illustrating the operation of the transmission characteristic measuring device on the timing detection side.

FIG. 11 is a flowchart illustrating the operation of the transmission characteristic measuring device on the synchronization side.

FIG. 12 is a configuration block diagram illustrating a specific example of a trigger detection unit that enables arbitrary setting of an event level.

FIG. 13 is an explanatory diagram showing an example of a TDR when an end point of a communication line is short-circuited.

FIG. 14 is an explanatory diagram illustrating an example of a TDR when an end point of a communication line is released.

FIG. 15 is a characteristic curve diagram showing an example of an obtained waveform and a synthesized waveform.

FIG. 16 is a flowchart showing the operation of the transmission characteristic measuring device.

FIG. 17 is an explanatory diagram illustrating an example of a topology display screen.

FIG. 18 is a flowchart illustrating the operation of the transmission characteristic measuring device.

FIG. 19 is a configuration block diagram illustrating an example of a conventional transmission characteristic measuring device.

FIG. 20 is a configuration block diagram showing an example of a conventional transmission characteristic measuring device.

FIG. 21 is a flowchart for explaining the operation of the conventional example.

[Explanation of symbols]

1, 2 measurement equipment 3, 3a user's house 4 main distributor 5 line switching device 6 signal separation device 7 multiplexer 8 voice service device 9, 9a control device (network operation center) 10, 11, 34, 35 transmission characteristic measurement device 12 Personal computer 13 Wireless communication device 14 Receiving antenna 15 Short circuit opening means 16 Switching means 17, 25 Communication means 18 Measurement means 19 A / D converter 20 D / A converter 21, 22 Storage means 23 Control means 24 Trigger detection means 26 Power supply 27 Driving means 28 Switch circuit 29, 32 Comparator 30 Variable voltage source 31 Counter circuit 33 Control circuit 50, 50a Telephone station 51 Power control means 100, 100a, 100b, 100c Communication line to be measured 101, 103 Network 102 High-speed digital data Data signal 104 Event signal 105 a trigger signal 200 measurement terminal

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5K027 LL05 LL08 5K042 BA10 CA01 CA23 DA11 EA02 LA09

Claims (19)

[Claims] An apparatus for measuring transmission characteristics of a communication line for communicating high-speed digital data, comprising: a first and a second transmission characteristic measuring device connected to both ends of a communication line to be measured; A transmission characteristic measuring device in which a transmission characteristic measuring device communicates using the communication line to be measured and transmits a reference signal to the communication line to be measured, and a receiving side which receives the reference signal and measures transmission characteristics. Setting the role of the transmission characteristic measuring device, and transferring the transmission characteristic data measured by the receiving-side transmission characteristic measuring device to the transmitting-side transmission characteristic measuring device via the communication line to be measured. Transmission characteristic measuring device. 2. An apparatus for measuring transmission characteristics of a communication line for communicating high-speed digital data, comprising: first and second transmission characteristic measuring devices connected to both ends of a communication line to be measured; and storing measured transmission characteristic data. A first transmission characteristic measuring device, wherein the first and second transmission characteristic measuring devices communicate using the communication line under test and transmit a reference signal to the communication line under measurement. And setting the role of a receiving-side transmission characteristic measuring device that receives the reference signal and measures transmission characteristics, and transmits the transmission characteristic data measured by the receiving-side transmission characteristic measuring device to the communication line to be measured. A transmission characteristic measuring device for transmitting the data to the control device via the control device. 3. The transmission characteristic measuring device according to claim 1, wherein the transmission characteristic measuring device on the receiving side transfers the transmission characteristic data via a public line. 4. The transmission characteristic measuring device according to claim 1, wherein the transmission characteristic measuring device on the receiving side transfers the transmission characteristic data using wireless communication. 5. The transmission according to claim 1, wherein the first or second transmission characteristic measuring device measures the transmission characteristic in synchronization with an externally input signal. Characteristic measuring device. 6. A trigger signal is detected from an external input signal input to the transmission characteristic measuring instrument on the transmitting side, and the trigger signal is transmitted to the transmission characteristic measuring instrument on the receiving side via the communication line to be measured. 3. The transmission characteristic measuring apparatus according to claim 1, wherein the transmission characteristic is measured in synchronization with the trigger signal received by the transmission characteristic measuring device on the receiving side. 7. The transmission characteristic measuring device, comprising: a short-circuit and open means for short-circuit-opening an end point of the communication line to be measured; a switch means for selecting an output of the short-circuit and open means; and an input / output of the switch means. A / is connected to an output of the communication means and the output of the switch means to receive an input signal.
A D converter, a D / A converter to which the input of the switch means is connected and which outputs the reference signal to the communication line to be measured, and a storage means for storing fetched data and data of the reference signal. 3. The transmission characteristic measuring device according to claim 1, further comprising control means for controlling the transmission characteristic and calculating the transmission characteristic from the data taken. 8. The control means controls the switch means to select the communication means. If there is no key operation, the control means waits for reception of a command from the communication line to be measured. In the case, it is determined whether a single measurement is possible or not. If the single measurement is possible, a measurement process is performed.If the single measurement is not possible, a command is transmitted to the communication line to be measured and connected to an end point. 8. The apparatus according to claim 7, wherein an instruction is given to another transmission characteristic measuring device and a measurement process is performed.
The transmission characteristic measuring device as described in the above. 9. The control means instructs a transmission characteristic measuring device on a receiving side to short-circuit an end point of the communication line to be measured, to flow a small current through the communication line to be measured and to communicate with the communication line to be measured. 8. The transmission characteristic measuring apparatus according to claim 7, wherein a voltage generated in the communication line is measured, and a resistance value is calculated from the minute current flowing through the communication line to be measured and the measured voltage value. 10. The control means instructs a transmission characteristic measuring device on the receiving side to open an end point of the communication line to be measured, and measures a capacity of the communication line to be measured having an open end point. The transmission characteristic measuring device according to claim 7, wherein: 11. A power supply control means for controlling supply of a power supply voltage to a main circuit, wherein said control means determines whether or not a specific pattern is received by said communication means, and said power supply is controlled when said specific pattern is received. The power supply voltage is supplied to the main circuit by controlling the control means, and the measurement end command is received by the communication means, or
8. The transmission characteristic measuring device according to claim 7, wherein when a preset time has elapsed, the power supply control means is controlled to cut off the supply of the power supply voltage to the main circuit. 12. The transmission according to claim 7, further comprising: trigger detection means for detecting a trigger signal from an external input signal, wherein said control means measures said transmission characteristic in synchronization with said trigger signal. Characteristic measuring device. 13. The control means detects a trigger signal from an external input signal, transmits a synchronization start command to the other transmission characteristic measuring instrument connected to the other end via the communication line to be measured, and transmits the trigger signal. The other transmission characteristic measuring device connected to the other transmission characteristic measuring device connected to the other end via the measured communication line, and a synchronization end command connected to the other end via the measured communication line. The transmission characteristic measuring apparatus according to claim 7, wherein the transmission is performed. 14. The control means receives the synchronization start command, receives the trigger signal, sets the cycle of the event timer while receiving the trigger signal, and at the time of receiving the synchronization end command, 8. The transmission characteristic measuring device according to claim 7, wherein the setting of the event timer is completed. 15. The trigger detecting means includes: a variable voltage source; a first comparator to which an output voltage of the variable voltage source and the external input signal are input; and a count of an output of the first comparator. A counter circuit that outputs a trigger signal when a count value of the counter circuit matches a set value; and a second comparator that controls a value of an output voltage of the variable voltage source and outputs the set value. 13. The transmission characteristic measuring apparatus according to claim 12, further comprising: a set number of times control circuit. 16. The control means instructs a transmission characteristic measuring device on the receiving side to output a pulse to the communication line under measurement in a state where an end point of the communication line to be measured is short-circuited, and measures a reflected pulse thereof. Instructing the transmission characteristic measuring device on the receiving side to output a pulse to the communication line to be measured in a state where the end point of the communication line to be measured is opened and measure the reflected pulse thereof, 8. The transmission characteristic measuring apparatus according to claim 7, wherein the position of the reflection point is specified by synthesizing the observed waveforms. 17. The control circuit according to claim 1, wherein the control unit instructs a transmission characteristic measuring device on a receiving side to measure a resistance value of the communication line under measurement in a state where an end point of the communication line under measurement is short-circuited. Instruct the measuring device to measure the capacitance value of the communication line under measurement in a state where the end point of the communication line under measurement is opened, output a pulse to the communication line under measurement, measure the reflected pulse, and measure the reflection point. The distance to the end point of the communication line to be measured, the position of the branch point,
Calculate the distance to the branch point and the distance of the branched communication line, the distance to the end point of the measured communication line, the position of the branch point,
8. A topology display of a distance to a branch point and a distance of a branched communication line on a display means.
The transmission characteristic measuring device as described in the above. 18. The control means displays a first straight line up to an end point of the communication line to be measured, and a second communication line branched from a position of a branch point of the first straight line. Numerical display of the distance to the end point of the communication line to be measured near the first straight line, and numerical display of the distance of the communication line branched near the second straight line, 18. The transmission characteristic measuring apparatus according to claim 17, wherein a distance from the transmission line to the branch point in the first straight line is numerically displayed near the branch point. 19. The control means measures a voltage of the communication line to be measured, determines whether the measured voltage exceeds a dangerous voltage, and determines whether the measured voltage exceeds the dangerous voltage. 8. The method according to claim 7, further comprising: generating an alarm and waiting for the operator to approve the measurement, and permitting the measurement of the communication line to be measured if the measurement is approved or the dangerous voltage is not exceeded. Transmission characteristic measuring device.