JP2021069055A - Error rate measuring instrument and error search method - Google Patents

Abstract

To search for symbols with errors including continuous errors in a PAM4 signal.SOLUTION: A data display device 1 includes error search means 7b that inputs, to a measured object W, a PAM4 signal of a known pattern consisting of a continuous range of three eye pattern openings obtained by dividing the entire amplitude voltage range H into a low voltage range, a medium voltage range, and a high voltage range from the lower voltage level as reference data, receives a signal from the measured object W with the input of the PAM4 signal, and searches for a symbol in which there is an error that satisfies an error search condition that displays data based on the received signal, and uses the number of error symbols and a voltage range, and from a symbol string on a display screen based on the symbol comparison result between the input data and the acquired error data.SELECTED DRAWING: Figure 1

Description

In the present invention, a PAM4 signal of a known pattern by a quadrature pulse amplitude modulation method (hereinafter referred to as PAM4 method) in which the amplitude is divided into four types for each symbol is input to an object to be measured as reference data, and the subject is accompanied by input of the reference data. The present invention relates to an error rate measuring device that receives a signal from a measurement object and displays data based on the received signal, and an error search method of the error rate measuring device that searches for a symbol having an error based on a symbol comparison result.

For example, as disclosed in Patent Document 1 below, the error rate measuring device transmits a test signal of a known pattern including fixed data to the object to be measured, and receives the test signal by returning from the object to be measured as the test signal is transmitted. It has been conventionally known as a device for measuring a bit error rate (BER) by comparing a measured signal and a reference reference signal on a bit-by-bit basis.

Japanese Unexamined Patent Publication No. 2007-274474

However, since the device disclosed in Patent Document 1 described above does not have an error search function, it is not possible to search for an error for each eye opening. Moreover, when errors are continuously inserted in the PAM4 signal, it is not possible to search for consecutive errors, so that it is necessary to search for consecutive errors that the user visually expects, which is a problem that labor and labor are required. was there.

Therefore, the present invention has been made in view of the above problems, and an object of the present invention is to provide an error rate measuring device and an error search method capable of searching for an error including a continuous error of a PAM4 signal.

In order to achieve the above object, the error rate measuring instrument according to claim 1 of the present invention has an overall amplitude voltage range H of low voltage range H1, medium voltage range H2, and high voltage range H3 from the lowest voltage level. A PAM4 signal of a known pattern consisting of a continuous range of three eye pattern openings divided into is input to the object to be measured W as reference data, and a signal from the object to be measured accompanying the input of the PAM4 signal is received. , An error rate measuring instrument that displays data based on the received signal.
Error search means 7b in which the number of error symbols and the voltage range are set as error search conditions, and a symbol having an error satisfying the error search condition is searched from a symbol string based on the symbol comparison result between the input data and the acquisition error data. It is characterized by having.

The error rate measuring device according to claim 2 of the present invention is the error rate measuring device according to claim 1.
A display control means 7c for identifying and displaying a symbol having an error searched by the error search means 7b is provided.

The error rate measuring device according to claim 3 of the present invention is the error rate measuring device according to claim 1.
A display control means 7c for displaying and controlling the total number of errors of a symbol having an error searched by the error search means 7b is provided.

The error rate measuring device according to claim 4 of the present invention is the error rate measuring device according to any one of claims 1 to 3.
The error search means 7b is moved to the position of a symbol having an error before and after satisfying the error search condition by a key operation starting from the position of an arbitrary symbol having an error satisfying the error search condition on the display screen. It is characterized by moving the cursor.

The error rate measuring device according to claim 5 of the present invention is the error rate measuring device according to any one of claims 1 to 4.
The feature is that the input data is taken in by setting any of the timing specified by the user, the timing when an error included in a specific pattern is detected, the timing of an external trigger from the object W to be measured, and the timing when an error is detected. To do.

The error search method of the error rate measuring instrument according to claim 6 of the present invention is divided into a low voltage range H1, a medium voltage range H2, and a high voltage range H3 from the lower voltage level of the entire amplitude voltage range H. A PAM4 signal of a known pattern consisting of a continuous range of three eye pattern openings is input to the object to be measured W as reference data, and a signal from the object to be measured accompanying the input of the PAM4 signal is received and received. This is an error search method for error rate measuring instruments that display signal-based data.
The number of error symbols and the voltage range are set as error search conditions, and a step of searching for a symbol having an error satisfying the error search condition from a symbol string based on the symbol comparison result between the input data and the acquisition error data is included. It is characterized by.

The error search method for the error rate measuring device according to claim 7 of the present invention is the error search method for the error rate measuring device according to claim 6.
It is characterized by including a step of identifying and displaying a symbol having the searched error.

The error search method for the error rate measuring device according to claim 8 of the present invention is the error search method for the error rate measuring device according to claim 6.
It is characterized by including a step of controlling the display of the total number of errors of the symbol having the searched error on the display screen.

The error search method for the error rate measuring device according to claim 9 of the present invention is the error search method for the error rate measuring device according to any one of claims 6 to 8.
Includes a step to move the cursor to the position of a symbol that has an error before and after satisfying the error search condition by a key operation starting from the position of an arbitrary symbol that has an error that satisfies the error search condition on the display screen. It is characterized by that.

The error search method for the error rate measuring device according to claim 10 of the present invention is the error search method for the error rate measuring device according to any one of claims 6 to 9.
Includes a step of capturing the input data with any of the timing specified by the user, the timing of detecting the error included in the specific pattern, the timing of the external trigger from the object W to be measured, and the timing of detecting the error as the setting timing. It is characterized by.

According to the present invention, a symbol having an error (including consecutive errors) of the PAM4 signal can be automatically searched without visually searching. As a result, the user can easily identify the location where the error occurs and debug it easily.

It is a block diagram which shows the schematic structure of the data display device which concerns on this invention. It is explanatory drawing of PAM4 signal. It is a figure which shows an example of the capture screen which includes the error count result of the data display device which concerns on this invention. It is a figure which shows an example of the capture screen at the time of error search of the data display device which concerns on this invention. Input data, acquisition error data, reference data, transition name, color of band-shaped display with respect to the waveform of the symbol, orientation of band-shaped display in amplitude direction, height of band-shaped display in amplitude direction, and band-shaped table in the data display device according to the present invention. It is a figure which shows an example of the correspondence table of the example. It is a figure which shows an example of the waveform image display, the symbol value display, and the band-shaped display in the data display device which concerns on this invention. It is a flowchart of the error count processing operation of the data display device which concerns on this invention. It is a flowchart of the error search processing operation of the data display device which concerns on this invention.

Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the attached drawings.

As shown in FIG. 1, the data display device 1 of the present embodiment uses a PAM4 signal of a known pattern having a four-value symbol value as a test signal in a state where the object W to be measured is transitioned to the signal pattern folding state. It is configured as an error rate measuring device 1A that transmits an object W to be measured and measures an error rate of input data that is returned and received from the object W to be measured in association with the transmission of this test signal.

In the data display device 1, an error that satisfies the error search condition is generated based on the symbol comparison result between the input data and the acquisition error data that are returned and received from the measurement object W when the test signal is transmitted to the measurement object W. It has an error search function for searching for a certain symbol, and includes a signal generator 2, an error detector 3, an operation unit 4, a storage unit 5, a display unit 6, and a control unit 7.

As shown in FIG. 1, the signal generator 2 is roughly configured to include a first signal generation unit 2a, a second signal generation unit 2b, and a signal synthesis output unit 2c, and is a desired symbol string (0) as a multi-valued signal. Generates a PAM4 signal consisting of data (a sequence of symbols consisting of 1, 2, and 3 symbol values).

The PAM4 signal is divided into four types of amplitudes for each symbol, and as shown in FIG. 2, has four different amplitude voltage levels V1, V2, V3, and V4, and the entire amplitude voltage range H is the voltage level. It is divided into a low voltage range H1, a medium voltage range H2, and a high voltage range H3 from the lowest, and consists of a continuous range with three eye pattern openings.

The first signal generation unit 2a adds the least significant bit string signal (LSB: Least Significant Bit) generated by the second signal generation unit 2b when generating a desired PAM4 symbol string consisting of a known pattern including fixed data. Generates the most significant bit string signal (MSB: Most Significant Bit) for generating the PAM4 signal.

The second signal generation unit 2b generates the lowest bit string signal for generating the PAM4 signal by adding the uppermost bit string signal generated by the first signal generation unit 2a.

The first signal generator 2a, a specific bit train signal by the second signal generator 2b generates, for example PRBS7 (pattern length: 2 ⁷ -1), PRBS9 (pattern length: 2 ⁹ -1), PRBS10 (pattern Various pseudo-random patterns (PRBS: Pseudo) such as length: 2 ^{10 -1), PRBS 11} (pattern length: 2 ^{11 -1), PRBS 15} (pattern length: 2 ^{15 -1), PRBS 20} (pattern length: 2 20 -1). There are periodic patterns such as Random Bit Sequence) and evaluation patterns for evaluating PAM such as PRBS13Q, PRBS31Q, and SSPRQ.

The signal synthesis output unit 2c outputs the PAM4 signal by adding the highest bit string signal generated by the first signal generation unit 2a and the lowest bit string signal generated by the second signal generation unit 2b. This PAM4 signal is input to the object W to be measured as a test signal of a known pattern when measuring the error rate of the object W to be measured.

When the PAM4 signal, which is reference data, is input from the signal generator 2 as a test signal of a known pattern to the object to be measured, the error detector 3 is output from the object to be measured W in accordance with the input of the PAM4 signal. As shown in FIG. 1, it includes a signal receiving unit 3a, a synchronization detection unit 3b, a position information storage unit 3c, a symbol comparison unit 3d, and a comparison result data storage unit 3e. ..

The signal receiving unit 3a samples the PAM4 signal received from the object W to be measured at a predetermined sampling cycle and converts it into a symbol string (a string of symbols composed of 0, 1, 2, and 3 symbol values). The symbol string data (hereinafter, also referred to as symbol data) converted by the signal receiving unit 3a is input to the synchronization detection unit 3b.

The synchronization detection unit 3b receives the reference data, which is the data of the symbol string of the reference PAM4 signal read from the storage unit 5, and the signal received from the object W to be measured, according to the set timing preset by the operation unit 4. The PAM4 signal output from the receiving unit 3a is synchronized with the symbol data, and the captured symbol data is output to the symbol comparison unit 3d.

The setting timing is set in advance by the operation unit 4 on the setting screen (not shown) of the display unit 6, for example, the timing of receiving the symbol data of the pattern matching the specific pattern including the error, and the object W to be measured is the trigger signal. Is generated, a trigger signal is generated by a user's instruction (for example, a button operation), and an error is detected.

The synchronization detection unit 3b notifies the symbol comparison unit 3d to that effect when synchronization is achieved, and stores the synchronization position indicating the position of the symbol in the reference data when synchronization is achieved in the position information storage unit 3c.

The position information storage unit 3c represents the position of the symbol in the reference data when the synchronization detection unit 3b synchronizes the reference data with the symbol data of the PAM4 signal from the signal reception unit 3a. Memorize the synchronization position.

After synchronization is achieved by the synchronization detection unit 3b, the symbol comparison unit 3d performs synchronous detection in order from the symbol of the reference data at the position when the error rate measurement is started by the instruction of the user or the like via the operation unit 4. The input data (PAM4 symbol data received from the object W to be measured), which is the symbol string output from the unit 3b, and the symbol string of the reference data are sequentially compared to detect a symbol having an error. The symbol comparison unit 3d calculates, for example, the difference obtained by subtracting the input data symbol from the reference data symbol, calculates the symbol transition amount of the input data with respect to the reference data, and performs an exclusive logical sum of the input data and the reference data ( By taking XOR), acquisition error data representing an incorrect symbol position is acquired, a transition name is determined based on the table shown in FIG. 5, and comparison result data is generated.

When the waveform image display start operation is performed from the operation unit 4 or the waveform image display condition is satisfied, the symbol comparison unit 3d receives the position information of the symbol position of the reference data according to the display start operation or the display start condition. Is stored in the position information storage unit 3c together with the synchronization position. In addition, the position information of the synchronization position is set to 0, for example, and the position information of the next symbol is set as a serial number such as 1, 2, 3, ... It is stored in the information storage unit 3c.

The waveform image display start condition means, for example, a case where a preset symbol transition occurs, a case where a preset number of symbol transitions occur continuously, and the like.

When the waveform image display stop operation is performed from the operation unit 4 or the waveform image display stop condition is satisfied, the symbol comparison unit 3d responds to the display stop operation or positions the symbol position of the reference data that satisfies the display stop condition. Information is stored in the position information storage unit 3c.

The waveform image display stop condition means, for example, a case where symbol transitions do not occur in a predetermined number of consecutive preset numbers.

The comparison result data storage unit 3e stores the comparison result data by the symbol comparison unit 3d together with the symbol data synchronized with the reference data. The comparison result data is, for example, in each of the symbols of the input data, in a symbol having no error compared to the reference data, that is, a transition name indicating that there is no symbol transition, and a symbol having an error compared to the reference data, for example. It contains information for distinguishing symbol transitions, that is, a plurality of transition names based on the transition amount and the transition direction for each symbol of the four PAM symbols of the PAM4 signal.

The operation unit 4 also functions as a setting means, and is provided with a user interface such as an operation knob, various keys, switches, buttons, and soft keys on the display screen of the display unit 6 provided in the data display device 1 of FIG. It is composed. The operation unit 4 sets the setting timing, specifies the block of symbol data displayed on the display screen of the display unit 6 (capture screen 6a in FIGS. 3 and 4), sets the baud rate, the generation condition of the symbol string, and the like. Make various settings related to error rate measurement of PAM4 signals, such as instructions for starting and ending error rate measurement.

The storage unit 5 stores a symbol string (a string of symbols consisting of 0, 1, 2, and 3 symbol values) of the PAM4 signal input to the object W as a test signal of a known pattern from the signal synthesis output unit 2c. .. The symbol string of the PAM4 signal input to the object W to be measured as a test signal of this known pattern is reference data as a reference when compared with the input data generated from the signal received from the object W to be measured.

The storage unit 5 stores information such as setting timing, baud rate, symbol string generation condition, waveform image display start condition, and waveform image display stop condition. These pieces of information can be appropriately selected and set by the operation unit 4 via the user interface.

The storage unit 5 is the result of error counting by the error counting means 7a described later of the control unit 7 (the total number of symbols having an error for each of the low voltage range H1, the medium voltage range H2, and the high voltage range H3, and the total amplitude voltage range H. Stores the total number of symbols with consecutive errors in.

If the control unit 7, the first signal generation unit 2a, and the second signal generation unit 2b can grasp the symbol string of the PAM4 signal to be the test signal, the control unit 7, the first signal generation unit 2a, and the second signal generation unit 2a. 2 The symbol string of the PAM4 signal, which is a test signal of a known pattern, that is, reference data may be stored in the storage unit 5 from the signal generation unit 2b.

The display unit 6 is composed of, for example, a liquid crystal display provided in the data display device 1 of FIG. 1, a setting screen related to error rate measurement, and each compliance test (test of whether or not the object W to be measured conforms to a communication standard). ) And the error rate measurement screen are displayed. Further, the display unit 6 also has an operation function of the operation unit 4 such as a soft key on the display screen.

The display unit 6 displays the symbol data stored in the comparison result data storage unit 3e on the capture screen 6a in block units under the control of the display control means 7a described later. In the present embodiment, one block is a block of symbol data that can be displayed in one display area (display size including scroll display) of the display unit 6. For example, when the allocated storage capacity is 8 Mbits (corresponding to 4 Msymbol of symbol data) and a block of symbol data that can be displayed in one display area of the display unit 6 is one block, one block = 65536 bits = 32768 symbols and 4 Msymbol The symbol data of No. 1 is divided into a predetermined number of divisions (any of 1, 2, 4, 8, 16, 32, 64, 128) and stored in the comparison result data storage unit 3e.

The maximum number of divisions of the symbol data is determined according to the storage capacity allocated to the comparison result data storage unit 3e. For example, if the storage capacity allocated to the comparison result data storage unit 3e is 8 Mbits, the maximum number of divisions of the symbol data is 128 divisions.

3 and 4 show a display example of the capture screen 6a of the display unit 6. “Block” and “Block Length” are displayed in the upper right area of the capture screen 6a of FIGS. 3 and 4. In "Block", an input box 11 for numerically inputting the number block of the symbol data to be displayed on the capture screen 6a is displayed. In "Block Length", the size (length) of the symbol data for one block is displayed. In the examples of FIGS. 3 and 4, "1" is input to the input box 11 of "Block", and "Block Length" is displayed as "32768" symbol. In the input box 11 of "Block", it is possible to set and input up to the number of divided blocks (for example, 1 to 128) determined according to the storage capacity of the storage unit 5.

In the area under "Block Length" on the capture screen 6a, "Viewer Mode" (viewing mode) used for debugging is displayed. In "Notation" of "Viewer Mode", the notation of the data to be displayed on the capture screen 6a ("Bin" (NRZ mode only), "Hex" (NRZ mode only), "Symbol" (PAM4 mode only)) The input box 12 to be specified is displayed. The "Format" of the "Viewer Mode" includes the data display format on the capture screen 6a ("Pattern" (symbol value display pattern data only), "Pattern + Waveform" (as shown in FIG. 6, symbol value display pattern). An input box 13 for specifying (for example, displaying a waveform image by a blue line)) is displayed on the data. The notation and display format of these data are selected and set from the respective pull-down menus. In the examples of FIGS. 3 and 4, "Symbol (PAM4)" is selected from the pull-down menu of the input box 12 of "Notation", and "Pattern" is selected from the pull-down menu of the input box 13 of "Format". Is shown.

"Error" is displayed in the area under "Viewer Mode" on the capture screen 6a. In "Error", check boxes 14, 15, 16, 17, 18, and 19 for displaying in the color corresponding to the transition of the symbol in which the error occurred are displayed for each symbol transition. In the examples of FIGS. 3 and 4, Lower (low voltage range H1) displayed in red: check box 14 for the transition of the symbol of “0” → “1” or “1” → “0”, and Middle displayed in yellow. (Medium voltage range H2): Check box 15 for transition of symbols of "1" → "2" or "2" → "1", Upper displayed in blue (High voltage range H3): "2" → "3" Or check box 16 of the transition of the symbol of "3" → "2", Middle (medium voltage range H2) / Lower (low voltage range H1) displayed in orange: "0" → "2" or "2" → " Check box 17 for transition of symbol of "0", Upper (high voltage range H3) / Middle (medium voltage range H2) displayed in green: Transition of symbol of "1" → "3" or "3" → "1" Check box 18, Upper (high voltage range H3) / Middle (medium voltage range H2) / Lower (low voltage range H1) displayed in purple: “0” → “3” or “3” → “0” symbol The check boxes 19 of the transitions of are checked.

In the area under "Error" of the capture screen 6a, "Move and Search" for searching a specific pattern is displayed. In "Move and Search", an input box 20 for inputting a specific pattern to be searched is displayed, and a magnifying glass button 21 is used to perform a search before and after.

In the area under "Move and Search" on the capture screen 6a, "Error Search" is displayed. In "Error Search", "Continuous Error" and "Target" for setting error search conditions are displayed. In "Continuous Error", input boxes 22 and 23 for setting a symbol to be searched for an error using an equal sign (=), an inequality sign with an equal sign (≧), and a number are displayed. In "Target", an input box 24 for selecting and setting a voltage range (any of the entire amplitude voltage range H, low voltage range H1, medium voltage range H2, and high voltage range H3) to be searched for an error from a pull-down menu. Is displayed.

In the example of FIG. 3, “≧” is input to the input box 22, “1” is input to the input box 23, and “All (overall amplitude voltage range H)” is input to the input box 24 as the error search condition. It shows a state in which all errors of one symbol or more are set as error search conditions (error search targets) in the entire amplitude voltage range H.

Further, in the example of FIG. 4, “≧” is input to the input box 22, “10” is input to the input box 23, and “All (overall amplitude voltage range H)” is input to the input box 24 as the error search condition. Is input, indicating a state in which all errors of 10 symbols or more in the entire amplitude voltage range H are set as error search conditions (error search targets).

In the area under "Target", the soft key 25 for moving the cursor on the capture screen 6a to the position of the first error symbol, and the cursor on the capture screen 6a to the position of the previous error symbol. Soft key 26 for moving, soft key 27 for moving the cursor on the capture screen 6a to the position of the symbol of the next error, moving the cursor on the capture screen 6a to the position of the symbol of the last error Soft key 28 for is displayed.

In the data display area 29 on the left side of "Block Length" of the capture screen 6a, symbol data for one block based on the input data is displayed with the vertical axis on the display as the address and the horizontal axis as the symbol. In the examples of FIGS. 3 and 4, a state in which a part of the symbol data of 32768 symbols is displayed in the data display area 29 as the symbol data for one block is shown. The symbol data that cannot be displayed in the data display area 29 can be displayed and confirmed in the data display area 29 by using the scroll bar 30 on the right side.

At the bottom of the data display area 29 on the capture screen 6a, the soft key 31 instructing the data display area 29 to display the symbol data of the first block, and the symbol data of the previous block are displayed in the data display area 29. Soft key 32 instructing to display the symbol data of the next block, soft key 33 instructing to display the symbol data of the next block in the data display area 29, and instructing to display the symbol data of the last block in the data display area 29. The soft key 34 to be used is displayed.

In the area at the bottom of the capture screen 6a, as a result of the error count, "First Error Block / Addless", "Last Error Block / Addless", "Error Counts Upper / Middle / Lower", "Contour" "Error" is displayed. In the display box 35 of "First Error Block / Addless", the block and the address of the place where the error first occurred are displayed. In the display box 36 of "Last Error Block / Addless", the block and the address of the place where the error last occurred are displayed. In the display box 37 of "Error Counts Upper / Middle / Lower", the total number of symbols having an error is displayed for each of the low voltage range H1, the medium voltage range H2, and the high voltage range H3. In the display box 38 of "Continuous Error Counts", the total number of symbols having continuous errors in the entire amplitude voltage range H is displayed. The number of capture acquisition bits is displayed in the display box 39 of "Capture Depth".

In order to measure the error rate of the PAM4 signal, the control unit 7 is composed of storage elements such as a central processing unit (CPU), ROM, and RAM, and is composed of a signal generator 2, an error detector 3, an operation unit 4, and a storage unit. 5. The display unit 6 is collectively controlled, and includes an error counting means 7a, an error searching means 7b, and a display controlling means 7c.

The error counting means 7a has an error (including continuous errors) for each of the low voltage range H1, the medium voltage range H2, and the high voltage range H3 based on the symbol data based on the comparison result stored in the comparison result data storage unit 3e. (Error)) and symbols with consecutive errors (all consecutive errors equal to or greater than the number of symbols specified in advance) in the entire amplitude voltage range H are counted.

The error search means 7b satisfies the error search condition from the symbol string based on the symbol comparison result between the input data and the acquisition error data captured at the preset timing, using the number of error symbols and the voltage range as the error search conditions. Search for symbols that have an error. For example, as shown in FIG. 4, the input box 22 of “Continuous Error” of “Error Search” of the capture screen 6a is set to “≧”, the input box 23 is set to “10”, and the input box 24 of “Taget” is set to “10”. When "All (overall amplitude voltage range H)" is set, the number of error symbols: "10 or more" and the voltage range: "overall amplitude voltage range H" are set as error search conditions, and the input data and acquisition are obtained. From the symbol string based on the symbol comparison result with the error data, a symbol having an error satisfying the error search condition, that is, a symbol having 10 or more consecutive errors in the entire amplitude voltage range H is searched.

The error search means 7b has an error that satisfies the error search condition in which the cursor is located on the capture screen 6a of the display unit 6. An error before and after the error search condition is satisfied by a key operation starting from the position of an arbitrary symbol. Move the cursor to the position of a symbol. Specifically, as shown in FIG. 4, the capture screen is obtained by selectively pressing the four soft keys 25, 26, 27, and 28 displayed in the area under "Target" of "Error Search". The cursor located on any symbol with an error on 6a, the position of the symbol with the first error, the position of the symbol with the previous error, the position of the symbol with the next error, and the last error You can move it to the position of a certain symbol.

The display control means 7c determines the frequency of symbols having an error for each voltage range (low voltage range H1, medium voltage range H2, high voltage range H3, overall amplitude voltage range H) based on the result of the error counting means 7a. Display numerical values on the display screen. Specifically, as shown in FIG. 3, a symbol having an error in each of the low voltage range H1, the medium voltage range H2, and the high voltage range H3 in the display box 37 of "Error Counts Upper / Middle / Lower" on the capture screen 6a. Is displayed, and the display box 38 of "Continuous Error Counts" displays the total number of symbols having continuous errors in the entire amplitude voltage range H. In the example of FIG. 3, the total number of symbols having an error in the low voltage range H1: "6266", the total number of symbols having an error in the medium voltage range H2: "12522", the total number of symbols having an error in the high voltage range H3: "6256", the total number of symbols having continuous errors in the entire amplitude voltage range H: "12522" is displayed.

The display control means 7c identifies and displays the position of the symbol having an error based on the result of the error counting means 7a. Specifically, based on the result of the error counting means 7a, the position of the symbol having an error is identified and displayed according to the strip-shaped display example (display form example) of the table of FIG. In the example of FIG. 3, according to the strip-shaped display example (display form example) of the table of FIG. 5, the symbol “2” of the address “50” of the data display area 16 of the capture screen 6a is orange, and the symbol “1” of the address “106”. "Is green, and the symbol" 3 "of the address" 562 "is identified and displayed in green.

The display control means 7c identifies and displays the position of the symbol having the error searched by the error search means 7b. Specifically, the position of the symbol having an error searched by the error search means 7b is identified and displayed according to the strip-shaped display example (display form example) of the table of FIG. In the example of FIG. 4, according to the strip-shaped display example (display form example) of the table of FIG. 5, the symbols “2” of the address “114” of the data display area 16 of the capture screen 6a, the symbols “2” of “116”, and “ The symbol "1" of "118", the symbol "2" of "120", the symbol "0" of "125" is orange, the symbol "1" of the address "115", the symbol "1" of "117", "119" The symbol "1", the symbol "3" of "121-124", and the symbol "3" of "126,127" are identified and displayed in green.

The display control means 7c controls the display of the total number of errors of the symbols having an error searched by the error search means 7b on the display screen of the display unit 6. Specifically, the total number of errors of the symbol having an error searched by the error search means 7b is displayed in the display box 38 of "Continuous Error Counts" on the capture screen 6a of FIG. In the example of FIG. 4, the number of error symbols: "10 or more", the voltage range: the total number of errors of symbols in which the error searched by the error search means 7b is 10 or more consecutive with the error search condition "overall amplitude voltage range H": “384” indicates a state displayed in the display box 38 of “Continuous Error Counts” on the capture screen 6a.

The display control means 7b displays the symbol value display and the waveform image display on the display unit 6 based on the symbol value of the input data of the symbol comparison unit 3d. More specifically, in the symbol value display, as shown in FIG. 6, the numbers of the symbol values of 0, 1, 2, and 3 of the input data are displayed on the display unit 6 according to the corresponding symbol values of the waveform image. To do. Further, as shown in FIG. 6, the waveform image display is such that the height in the amplitude direction is adjusted to the symbol values of 0, 1, 2, and 3 of the input data, and the width in the time axis direction for each symbol value. Is displayed on the display unit 6. At that time, the numbers displayed in the symbol value display should be bordered so as not to impair the visibility of the numbers with respect to the background color and pattern of the display screen, the line type and color of the waveform in the waveform image display. To do. In addition, it is desirable that the numbers on the symbol value display and the color of the waveform on the waveform image display are different colors. Further, when the waveform of the waveform image display overlaps with the number of the symbol value display, the line of the corresponding waveform of the waveform image may be displayed as a dotted line or the like so that the number can be easily seen. The execution order of the symbol value display and the waveform image display may be in any order or may be executed simultaneously.

The display control means 7b responds to the waveform image display of the input data based on the comparison result data of the comparison data storage unit 3d, for example, according to the strip-shaped display example of FIG. 5, and corresponds to the transition name of each symbol. The color of the band-shaped display, the direction of the band-shaped display in the amplitude direction, and the height of the band-shaped display in the amplitude direction are superimposed and displayed.

The execution order of the symbol value display, the waveform image display, and the band-shaped display may be in any order or may be executed simultaneously. Further, the band-shaped display may be arbitrarily displayed or hidden by the user's operation from the operation unit 4 in the state where the symbol value is displayed and the waveform image is displayed.

In addition, since there are 12 types of symbol transitions, the number of colors is large when 12 colors are color-coded, and it is difficult to understand at a glance what kind of error occurred, that is, what kind of symbol transition occurred. As shown, as the display form, for example, the symbol transition from symbol 0 to 1 and the symbol transition from symbol 1 to 0 are unified with the same color of red, for example, the symbol transition from symbol 1 to 2 and the symbol transition from symbol 2 to. The symbol transition to 1 may be unified with the same color of yellow, and other symbol transitions may be unified with the same color when the numbers of the symbol values are interchanged with each other. As a result, in the case of the example of FIG. 5, by making the relationship in which the numbers of the symbol values are interchanged with each other the same color, six colors are coded, and in addition to what kind of symbol transition has occurred, the eye opening It is easy to determine that the symbol is transitioning so that an error is inserted across one or more.

Further, in the relationship in which the numbers of the symbol values are interchanged with each other, the brightness, transparency or blinking cycle of the band-shaped display may be unified with the same brightness, the same transparency or the same blinking cycle, respectively. Similarly, a band-shaped display is also performed for the symbol at the position of the input data having a symbol error. An example of these display examples is shown in the strip-shaped display example of FIG. Further, the display form of the band-shaped display corresponding to each transition name is not limited to the identification by color, but may be the identification by the difference in brightness, transparency or blinking cycle, or a combination thereof.

The waveform image display start operation, waveform image display condition, waveform image display stop operation, and waveform image display stop condition detect, for example, a symbol string that appears at regular intervals when a symbol string having a specific pattern is detected. This includes the case, or the case where a start flag of data conforming to a known communication protocol is detected.

Next, the error count processing operation of the data display device 1 configured as described above will be described with reference to FIG. 7.

The signal generator 2 inputs the reference data based on the PAM4 signal of the known pattern into which the error is inserted into the object W to be measured (ST1). When the reference data is input to the object W to be measured, the signal receiving unit 3a samples the PAM4 signal received from the object W to be measured in accordance with the input of the reference data at a predetermined sampling cycle and converts it into a symbol string ( ST2).

Subsequently, the synchronization detection unit 3b synchronizes the reference data, which is the data of the symbol string of the reference PAM4 signal at the preset timing, with the symbol data based on the PAM4 signal received from the object W to be measured. Take (ST3). Then, the synchronization position representing the position of the symbol in the reference data at the time of synchronization is stored in the position information storage unit 3c, and the symbol data to be the input data is output.

After that, the symbol comparison unit 3d sequentially compares the synchronized symbols with the reference data in order from the symbol at the position when the error rate measurement is started, according to an instruction from the user or the like via the operation unit 4 (ST4). ). Then, a symbol having an error is detected, and the comparison result data, which is the result of the comparison, is stored in the comparison result data storage unit 3e.

Subsequently, the error counting means 7a counts the symbols having an error for each of the low voltage range H1, the medium voltage range H2, and the high voltage range H3 from the symbol string based on the comparison result stored in the comparison result data storage unit 3e. Count symbols with continuous errors in the entire amplitude voltage range H (ST5).

Then, the display unit 6 controls the error frequency of the entire amplitude voltage range H, low voltage range H1, medium voltage range H2, and high voltage range H3 based on the result of the error counting means 7a under the control of the display control means 7c. Numerical values are displayed on the display screen (ST6). For example, in the display box 37 of "Error Counts Upper / Middle / Lower" on the capture screen 6a of FIG. 3, the total number of symbols having an error for each of the low voltage range H1, the medium voltage range H2, and the high voltage range H3 is displayed, and "Continuous" is displayed. The display box 38 of "Error Counts" displays the total number of symbols having continuous errors in the entire amplitude voltage range H.

Further, the display unit 6 identifies and displays the position of the symbol having an error based on the result of the error counting means 7a under the control of the display controlling means 7c (ST7). For example, when the symbol "2" at the address "50", the symbol "1" at the address "106", and the symbol "3" at the address "562" in the data display area 16 of the capture screen 6a of FIG. 3 are symbols with errors. , The symbol "2" of the address "50" is orange, the symbol "1" of the address "106" is green, and the symbol "3" of the address "562" is green according to the strip-shaped display example (display form example) of the table of FIG. Identify and display with.

Further, when the "Notation" of the "Viewer Mode" is set to "Symbol" and the "Format" is set to "Pattern + Waveform" on the capture screen 6a, the display unit 6 is controlled by the display control means 7a, for example. As shown in 6, the symbol value display and the waveform image display are displayed based on the symbol value of the input data, and according to the band-shaped display example of FIG. 5, the waveform of the symbol corresponds to the transition name of each symbol. The colors of the band-shaped display, the orientation of the band-shaped display in the amplitude direction, and the height of the band-shaped display in the amplitude direction are superimposed and displayed. For example, in FIG. 6, the symbol of the second input data and the acquisition error data from the left is 1 (01), and the symbol of the input data is the symbol transition from the reference data 0 (00) to 1 (01). , As shown in FIG. 5, the transition name is "A2". The color of the band-shaped display corresponding to the transition name "A2" is "red", the direction of the band-shaped display in the amplitude direction is "down", and the height of the band-shaped display in the amplitude direction is "1 voltage range". As a result, with respect to the waveform image display at the second position from the left, a downward red band-shaped display is performed in one voltage range for the linear waveform.

When "Notation" of "Viewer Mode" is set to "Symbol" and "Format" is set to "Pattern" on the capture screen 6a, the band shape of FIG. 5 shows the symbol with an error with respect to the symbol value display. Band-shaped display is performed according to the display example (state in which the waveform image display of FIG. 6 is not displayed).

Next, the error search processing operation of the data display device 1 configured as described above will be described with reference to FIG.

With the error count processing described above performed, the operation unit 4 sets the error search conditions necessary for performing the error search (ST11). For example, on the capture screen 6a of FIG. 4, enter “≧” and “10” in the input box of “Continuous Error” of “Error Search”, and enter “All (overall amplitude voltage)” from the pull-down menu in the input box of “Target”. Select "Range H)" and set the error search conditions. As a result, a symbol having 10 or more consecutive errors in the entire amplitude voltage range H is set as an error search condition.

When the error search condition is set, the error search means 7b searches the symbol data of one block displayed on the capture screen 6a for a symbol having an error satisfying the error search condition (ST12). As shown in FIG. 4, for example, if a symbol having 10 or more consecutive errors in the entire amplitude voltage range H is an error search condition, a symbol satisfying this error search condition is captured as one block of symbol data on the capture screen 6a. Search from.

Then, the display control means 7c identifies and displays the position of the symbol having the error searched by the error search means 7b, and controls the display of the total number of errors of the symbol having the error searched by the error search means 7b on the capture screen. (ST13).

Then, if the soft key 25 of the capture screen 6a of FIG. 4 is pressed in the state of performing the error search described above, the cursor on the capture screen 6a moves to the position of the symbol having the error at the head. Further, each time the soft key 26 is pressed, the cursor on the capture screen 6a moves to the position of the symbol having the previous error. Further, each time the soft key 27 is pressed, the cursor on the capture screen 6a moves to the position of the symbol having an error one step later. If the soft key 28 is pressed, the cursor on the capture screen 6a moves to the position of the symbol having the last error.

The display unit 6 displays the symbol value display and the waveform image display based on the symbol value of the input data under the control of the display control means 7c, for example, as shown in FIG. 6, and follows the strip-shaped display example of FIG. , Corresponding to the transition name of each symbol, the color of the band-shaped display with respect to the waveform of the symbol, the direction of the band-shaped display in the amplitude direction, and the height of the band-shaped display in the amplitude direction are superimposed and displayed. For example, in FIG. 6, the symbol of the fifth reference data from the start of the waveform image display is 3 (11), but the symbol of the input data has transitioned to 2 (10), so as shown in FIG. , The transition name is "C2". The color of the band-shaped display corresponding to the transition name "C2" is "blue", the direction of the band-shaped display in the amplitude direction is "down", and the height of the band-shaped display in the amplitude direction is "1 voltage range". As a result, with respect to the waveform image display at the fifth position from the start of the waveform image display, a downward blue band-shaped display is performed in one voltage range for the linear waveform.

By the way, in the above-described embodiment, as shown in FIG. 1, the data display device 1 (error rate measuring device 1A) has a signal generator 2, an error detector 3, an operation unit 4, and a storage. Although the configuration includes the unit 5, the display unit 6, and the control unit 7, the configuration is not limited to this configuration. For example, the signal generator 2 and the error detector 3 may be modularized or individually housed separately, and the operation unit 4 and the display unit 6 may be configured by an external device such as a personal computer connected to the outside.

As described above, according to the present embodiment, in the error rate measuring device for measuring the error rate of the input digital signal, the eye opening of the PAM4 signal (overall amplitude voltage range H, based on the symbol comparison result, Symbols with errors (including continuous errors) in the low voltage range H1, the medium voltage range H2, and the high voltage range H3 can be automatically searched. As a result, even if errors are continuously inserted in the PAM4 signal, symbols with consecutive errors are automatically searched under the error search conditions equal to or greater than the set number of error symbols, so that the locations where continuous errors occur can be visually checked. It is possible to easily search without having to search with, and it is possible to visually grasp consecutive errors. As a result, the user can easily identify the location where an error (including consecutive errors) occurs by using this error search function, and it becomes easy to debug.

Although the best form of the error rate measuring device and the error search method according to the present invention has been described above, the present invention is not limited by the description and drawings in this form. That is, it goes without saying that all other forms, examples, operational techniques, and the like made by those skilled in the art based on this form are included in the scope of the present invention.

1 Data display device 1A Error rate measuring device 2 Signal generator 2a 1st signal generator 2b 2nd signal generator 2c Signal synthesis output 3 Error detector 3a Signal receiver 3b Synchronous detector 3c Position information storage 3d Symbol comparison Unit 3e Comparison result data storage unit 4 Operation unit 5 Storage unit 6 Display unit 6a Capture screen 7 Control unit 7a Error counting means 7b Display control means 11, 12, 13, 20, 22, 23, 24 Input boxes 14, 15, 16 , 17, 18, 19 Check box 21 Magnifying glass button 25, 26, 27, 28, 31, 32, 33, 34 Soft keys 29 Data display area 30 Scroll bar 35, 36, 37, 38, 39 Display box W Instrument

Claims (10)

The entire amplitude voltage range (H) is divided into a low voltage range (H1), a medium voltage range (H2), and a high voltage range (H3) from the lower voltage level to a continuous range of three eye pattern openings. Error rate measurement in which a PAM4 signal of a known pattern is input to an object to be measured (W) as reference data, a signal from the object to be measured accompanying the input of the PAM4 signal is received, and data based on the received signal is displayed. It ’s a vessel,
An error search means (an error search method) in which the number of error symbols and the voltage range are set as error search conditions, and a symbol having an error satisfying the error search condition is searched from a symbol string based on the symbol comparison result between the input data and the acquisition error data. An error rate measuring instrument comprising 7b). The error rate measuring device according to claim 1, further comprising a display control means (7c) for identifying and displaying a symbol having an error searched by the error search means (7b). The error rate measuring device according to claim 1, further comprising a display control means (7c) for displaying and controlling the total number of errors of a symbol having an error searched by the error search means (7b). The error search means (7b) is a key operation starting from the position of an arbitrary symbol having an error satisfying the error search condition on the display screen, so that the symbol having an error before and after satisfying the error search condition can be operated. The error rate measuring device according to any one of claims 1 to 3, wherein the cursor is moved to a position. The input data is taken in by setting any of the timing specified by the user, the timing when an error included in a specific pattern is detected, the timing of an external trigger from the object to be measured (W), and the timing when an error is detected. The error rate measuring device according to any one of claims 1 to 4. The entire amplitude voltage range (H) is divided into a low voltage range (H1), a medium voltage range (H2), and a high voltage range (H3) from the lower voltage level to a continuous range of three eye pattern openings. Error rate measurement in which a PAM4 signal of a known pattern is input to an object to be measured (W) as reference data, a signal from the object to be measured accompanying the input of the PAM4 signal is received, and data based on the received signal is displayed. It is an error search method of the vessel,
The number of error symbols and the voltage range are set as error search conditions, and a step of searching for a symbol having an error satisfying the error search condition from a symbol string based on the symbol comparison result between the input data and the reference data is included. An error search method for an error rate measuring instrument. The error search method for an error rate measuring instrument according to claim 6, further comprising a step of identifying and displaying a symbol having the searched error. The error search method for an error rate measuring instrument according to claim 6, further comprising a step of controlling the display of the total number of errors of the symbol having the searched error on the display screen. Includes a step to move the cursor to the position of a symbol that has an error before and after satisfying the error search condition by a key operation starting from the position of an arbitrary symbol that has an error that satisfies the error search condition on the display screen. The error search method for an error rate measuring instrument according to any one of claims 6 to 8, wherein the error rate measuring device is characterized. The step of capturing the input data is set to any of the timing specified by the user, the timing when an error included in the specific pattern is detected, the timing of the external trigger from the object to be measured (W), and the timing when the error is detected. The error search method for an error rate measuring instrument according to any one of claims 6 to 9, wherein the error rate measuring device is included.

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