JP5140717B2 - Jitter adding apparatus and jitter adding method - Google Patents

Description

  The present invention relates to a jitter adding apparatus and a jitter adding method for adding jitter with desired parameter settings to a signal to be added.

  In a digital transmission system, if a data signal phase jitter (phase fluctuation) or a signal time shift increases, the data signal cannot be transmitted normally. For this reason, the electronic devices used in this type of system and the components used in them need to satisfy the jitter tolerance (strength) standard defined by ITU-T (International Telecommunication Union-Telecommunication Standardization Sector). . This jitter tolerance standard is whether or not a signal having a predetermined amount of jitter can be output at a predetermined error rate when a signal having a predetermined amount of jitter is input to the device or part to be measured. It represents. In addition, the electronic devices used and the components used in them are PCI-SIG (PCI Special Interest Group) which develops and manages PCI (Peripheral Component Interconnect), which is a general-purpose extended interface standard, and related standards. It is necessary to satisfy the standards including the jitter tolerance (strength) standard specified in.

  Here, a jitter signal, which is a jitter-modulated signal for measuring the jitter tolerance, will be described with reference to FIG. The jitter signal b is a signal whose phase changes at a predetermined fluctuation speed and within a predetermined fluctuation range with respect to a reference rectangular wave signal a as a reference signal to be transmitted (a signal to which jitter is added). A range of phase fluctuation, that is, a phase fluctuation amount is defined as a jitter generation amount, and a phase fluctuation speed is defined as a modulation frequency.

  The unit of the jitter generation amount (hereinafter also referred to as “phase modulation amount”) is indicated by a multiple of the period (UI: Unit Interval) of the reference rectangular wave signal a. For example, the phase modulation amount at 90 ° is 0.25 UI, and the amount of jitter generated in one cycle is 1 UI. As an apparatus for transmitting a jitter-modulated signal while changing the modulation frequency and phase modulation amount as needed to a system under test including a device under test 100 (DUT: Device Under Test), etc., and performing a jitter tolerance test, for example, A jitter adding apparatus 300 disclosed in the following Patent Document 1 is known.

International Publication WO2009 / 041516

  By the way, in the conventional jitter adding apparatus including Patent Document 1, the modulation frequency and the phase modulation amount of the generated jitter signal b are arbitrarily set, and a sine wave jitter (SJ: sinusoidal jitter) generated from a sine wave, white Random jitter generated from noise (RJ: Random Jitter), for example, periodic jitter (PJ: Periodic Jitter) generated from periodic signals such as triangular wave and rectangular wave, and pseudo random pattern (PRBS: Pseudo Random Binary Sequence) The frequency distribution with respect to the jitter amplitude generated in this manner has various jitter types such as a periodic uncorrelated wave jitter (BUJ) that is close to a Gaussian distribution. Is generated. In the conventional jitter adding apparatus 300 illustrated in FIG. 10, for example, at least one jitter type desired to be generated displayed on the display unit 315 is set from the operation unit 310, and the modulation frequency and phase modulation desired to be generated are set. A numerical value is input, and jitter is added at the modulation frequency and phase modulation amount corresponding to the jitter type set in the jitter adding unit 314 with respect to the target signal 50 to which jitter is added by the control by the control unit 312. ing.

  Here, the output value of the jitter generation amount that can be output by the jitter adding apparatus 1 is limited by the jitter adding capability of the hardware of the jitter adding apparatus 1, and in general, when the target signal 50 to be added with jitter has a high frequency or In addition, the higher the modulation frequency, the larger the phase modulation amount cannot be applied. Then, the manufacturer of the jitter adding apparatus 1 defines the specifications of the apparatus for each jitter adding apparatus, with a value that can guarantee the output value of the jitter generation amount as a generation amount guaranteed value.

  When the jitter generation amount that can be output by the jitter adder reaches the guaranteed value, the operation to stop the jitter generation because the output value of the jitter generation cannot be guaranteed. However, depending on the user, even if the output value of the jitter generation amount has reached the generation amount guarantee value, the jitter generation amount that can be guaranteed to confirm the margin of the jitter tolerance of the device under test 100 However, it is desired to continue the test with a further jitter generation amount up to the upper limit value of the output value that can be generated by the jitter adding device, that is, the generation amount upper limit value.

  However, in the conventional jitter adding apparatus, when generating jitter having various jitter types, the output value of the jitter generation amount that can be output by the jitter adding apparatus has reached the generation amount guarantee value that is a guaranteeable value. Even if this is the case, the user cannot grasp that the output value of the jitter generation amount has reached the guaranteed amount of generation, and when the output of multiple jitter types is performed simultaneously, the output value of the jitter generation amount However, there is a problem that cannot be grasped though it is easy to exceed the guaranteed amount of generation, and a solution has been desired.

  Furthermore, even if the upper limit value of the output value that can be generated by the jitter adding device is defined as a device specification for each jitter adding device, the user cannot easily grasp that value has been reached. There was a desire for a solution.

  Therefore, the present invention has been made in view of the above problems, and when generating jitter having various jitter types, the output value of the jitter generation amount of the jitter adding device reaches the generation guaranteed value. Even so, the user can intuitively know that the output value of the jitter generation amount has reached the guaranteed amount of generation while continuing the test with a further amount of jitter generation. To provide a jitter addition apparatus and a jitter addition method that allow a user to intuitively grasp that an output value of jitter generation amount has reached the generation amount upper limit value even when the amount upper limit value has been reached. It is the purpose.

In order to achieve the above-described object, the jitter adding apparatus according to claim 1 is configured to arbitrarily set a parameter including the amount of jitter generation in order to add jitter to a target signal (50) to which jitter is added. An operation unit (10) for setting and arbitrarily setting a plurality of jitter types from a jitter type that is a type to which the jitter is added;
In a jitter adding device (1) comprising a jitter adding unit (14) for adding the jitter,
A jitter generation amount storage unit (13) that stores in advance generation amount guarantee values, which are values that can guarantee the amount of jitter generation, in advance as parameter values in association with the combinations of the plurality of jitter types;
A generation amount guarantee value determination unit (12b) for determining whether or not the arbitrarily set jitter generation amount has reached the generation amount guarantee value stored in the jitter generation amount storage unit; And

The jitter adding apparatus according to claim 2 is the jitter adding apparatus (1) according to claim 1,
The parameter value includes at least a total amount of jitter generation corresponding to a modulation frequency that is a phase fluctuation speed of the jitter in the combination of the jitter types.

The jitter adding apparatus according to claim 3 is the jitter adding apparatus according to claim 1 or 2,
When the arbitrarily set jitter generation amount reaches the generation amount guarantee value stored in the jitter generation amount storage unit, the display unit (15) displays that the generation amount guarantee value has been reached. A control unit (12d) is provided.

The jitter adding apparatus according to claim 4 is the jitter adding apparatus according to claim 3,
In the jitter generation amount storage unit, a generation amount upper limit value, which is an upper limit at which an output value of the jitter generation amount can be generated, is stored in advance as a parameter value corresponding to each combination of the plurality of jitter types,
A generation amount upper limit determination unit (12c) for determining whether or not the arbitrarily set jitter generation amount has reached the generation amount upper limit value stored in the jitter generation amount storage unit;
The display control unit indicates that the generation amount upper limit value is reached when the arbitrarily set jitter generation amount reaches the generation amount upper limit value stored in the jitter generation amount storage unit. It is characterized by being displayed.

In order to achieve the above-mentioned object, the jitter adding method according to claim 5 is based on a jitter type which is a type to which jitter is added in order to add jitter to a target signal (50) to which jitter is added. Jitter type setting step (S202) for setting an arbitrary plurality of jitter types;
A jitter addition method including a jitter generation amount setting step (S203) for arbitrarily setting the jitter generation amount;
A jitter generation amount guarantee value storing step (S201) for preliminarily storing as a parameter value a generation amount guarantee value that is a value that can guarantee the output value of the jitter generation amount;
Generation amount guarantee value determination step for determining whether or not the jitter generation amount arbitrarily set in the jitter generation amount setting step has reached the generation amount guarantee value stored in the jitter generation amount guarantee value storage step. (S206).

The jitter addition method according to claim 6 is the jitter addition method according to claim 5,
The parameter value includes at least a total amount of jitter generation corresponding to a modulation frequency that is a phase fluctuation speed of the jitter in the combination of the jitter types.

The jitter addition method according to claim 7 is the jitter addition method according to claim 5 or 6,
A guarantee value display step (S207) for displaying that the jitter generation amount arbitrarily set in the jitter generation amount setting step has reached the generation amount guarantee value.

The jitter addition method according to claim 8 is the jitter addition method according to claim 7,
A jitter generation amount upper limit storage step (S208) for preliminarily storing the generation amount upper limit value, which is an upper limit at which an output value of the jitter generation amount can be generated, corresponding to each combination of the plurality of jitter types as a parameter value;
Generation amount upper limit determination step for determining whether or not the jitter generation amount arbitrarily set in the jitter generation amount setting step has reached the generation amount upper limit value stored in the jitter generation amount upper limit value storage step. (S209),
And an upper limit value display step (S210) for displaying that the generated amount upper limit value has been reached.

  According to the jitter adding apparatus of the present invention, the generation amount guarantee value, which is a value that can guarantee the output value of the jitter generation amount, is stored in advance as a parameter value in association with each combination of a plurality of jitter types, and is arbitrarily set Since it is determined whether or not the amount of generated jitter has reached the guaranteed amount of generation, when generating jitter having various jitter types, the output value of the amount of jitter generated by the jitter adding device is Even when the guaranteed value is reached, the user can intuitively grasp that the output value of the jitter generation amount has reached the generation amount guaranteed value while continuing the test with the further jitter generation amount.

  Further, according to the jitter adding apparatus of the present invention, the generation amount upper limit value, which is the upper limit at which the output value of the jitter generation amount can be generated, is stored in advance as a parameter value corresponding to each combination of a plurality of jitter types. It is determined whether or not the jitter generation amount set in (1) has reached the generation amount upper limit value, and when the arbitrarily set jitter generation amount has reached the generation amount upper limit value, it is confirmed that the generation amount upper limit value has been reached. Since it is displayed on the display section, even when jitter having various jitter types is generated, even when the output value of the jitter generation amount of the jitter adding device reaches the upper limit value of the jitter generation amount The user can intuitively grasp that the output value of the jitter generation amount has reached the generation amount upper limit value.

It is a schematic block diagram which shows the apparatus structure of the jitter addition apparatus which concerns on this invention. It is a figure which shows the relationship between a reference | standard rectangular wave signal and the signal by which the jitter modulation was carried out. It is a figure which shows the structural example of the table of the jitter generation amount memory | storage part in the apparatus structure of the jitter addition apparatus which concerns on this invention. It is a figure which shows the example of a display screen of the jitter addition apparatus which concerns on this invention. It is a processing sequence figure showing an example of processing operation of the device. It is a processing sequence figure showing another example of processing operation of the device. It is a flowchart which shows an example of the software processing operation | movement of the apparatus. It is a flowchart which shows another example of the software processing operation | movement of the apparatus. It is a flowchart which shows another example of the software processing operation | movement of the apparatus. It is a schematic block diagram which shows the apparatus structure of the conventional jitter addition apparatus.

  Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the accompanying drawings. It should be noted that the present invention is not limited by this embodiment, and all other forms, examples, operational techniques, etc. that can be implemented by those skilled in the art based on this form are included in the scope of the present invention. .

  First, the configuration of the jitter adding apparatus according to the present invention will be described with reference to FIG. The jitter adding apparatus 1 of this example transmits a signal with jitter added to a device under test 100 (DUT: Device Under Test) such as a device under test or a part to be tested, and the device under test 100 has a predetermined amount. For a signal generated internally or externally to which jitter is to be added (hereinafter referred to as “target signal”), provided on the transmission side in a test system that tests whether a signal having jitter can be output at a predetermined error rate, etc. A signal to which jitter having arbitrarily set parameters of modulation frequency (f) and phase modulation amount (UI) is added is output.

  As shown in FIG. 1, the jitter adding apparatus 1 of the present example includes an operation unit 10, a jitter type setting unit 11, a control unit 12, a total amount calculation unit 12a, a generation amount guaranteed value determination unit 12b, and a generation amount upper limit determination unit 12c. A display control unit 12d, a jitter generation amount storage unit 13, a jitter addition unit 14, a display unit 15, and a table 20.

  The operation unit 10 includes input devices such as a keyboard, a button, a mouse, and a touch panel in order to set setting items necessary for driving the device on the display screen of the display unit 15. The jitter type setting unit 11 includes, for example, a button for setting an arbitrary jitter type from various jitter types to the operation unit 10. Here, the jitter type is the type of jitter added to the target signal 50, for example, sinusoidal jitter (SJ), random jitter (RJ), and periodic uncorrelated wave jitter (BUJ). Uncorrelated Jitter). When at least one jitter type is set, the jitter type setting unit 11 outputs the set jitter type information to the control unit 12 as jitter type setting information.

  The operation unit 10 also includes buttons and the like that can set values for arbitrarily setting the modulation frequency and phase modulation amount of the generated jitter signal b. Therefore, the user can arbitrarily set the modulation frequency and the phase modulation amount of the jitter signal b added to the target signal 50 while viewing the display screen. The operation unit 10 then outputs the set modulation frequency and phase modulation amount information to the control unit 12 as modulation frequency information and phase modulation amount information. Further, when the target signal 50 is generated inside the jitter adding apparatus 1, the operation unit 10 may arbitrarily set the frequency.

  The jitter generation amount storage unit 13 stores parameter values, and is configured, for example, in the form of a table shown in FIG. Each item in FIG. 3 includes a jitter generation guarantee value 81 at each jitter modulation frequency corresponding to a generated jitter type 80 indicating a combination of a plurality of arbitrarily set jitter types, and a jitter amount at each jitter modulation frequency. The generation amount upper limit value 82 is set.

  Specifically, in the table 20 shown in FIG. 3, a generated jitter type 80 indicating a combination of a plurality of arbitrarily set jitter types, and a generated amount corresponding to each of the plurality of jitter types included in the generated jitter type 80 A guaranteed value 81 and a generated amount upper limit value 82 corresponding to each of a plurality of jitter types included in the generated jitter type 80 are stored. Further, the generated amount guarantee value 81 for each generated jitter type 80 is stored as a generated amount guaranteed value within a range of a plurality of modulation frequencies.

  For example, when the generated jitter type 80 is “SJ + PJ”, the generated amount guarantee value 81 is “60.71 UI (@ 10-1 MHz)”, “12.14 UI (@ 1M-10 MHz)”, “0.85 UI”. (@ 10M-250 MHz) ", the generated amount guarantee value within each modulation frequency range is stored.

  The generation amount upper limit value 82 for each generated jitter type 80 is stored as a generation amount upper limit value within a range of a plurality of modulation frequencies.

  Specifically, in the table shown in FIG. 3, a generated jitter type 80 indicating a combination of a plurality of arbitrarily set jitter types, and a generated amount upper limit corresponding to each of the plurality of jitter types included in the generated jitter type 80, respectively. A value 82 and a generation amount upper limit value 82 corresponding to each of a plurality of jitter types included in the generated jitter type 80 are stored. Further, the generation amount upper limit value 82 for each generated jitter type 80 is stored as a generation amount upper limit value within a range of a plurality of modulation frequencies.

  For example, when the generated jitter type 80 is “SJ + PJ”, the upper limit 82 of the generated amount is “91 UI (@ 10-1 MHz)”, “18.21 UI (@ 1M-10 MHz)”, “1.275 UI (@ 10M-250 MHz) ", and the generation amount upper limit value within the range of each modulation frequency.

  The control unit 12 is composed of, for example, a microcomputer such as a CPU, a ROM, or a RAM, and a generated jitter type 80 and a generated jitter type 80 that are combinations of a plurality of arbitrarily set jitter types of the arbitrarily set jitter signal b. The total amount calculation unit 12a that calculates the total amount of jitter generation corresponding to the modulation frequency and phase modulation amount arbitrarily set for each of the plurality of jitter types included in the memory, and the calculated total amount is stored in the jitter generation amount storage unit 13 Generation amount guaranteed value determination unit 12b for determining whether or not the generated amount guaranteed value 81 has been reached, whether or not the calculated total amount has reached the generation amount upper limit value 82 stored in the jitter generation amount storage unit 13 The generation amount upper limit determination unit 12c for determining the display and the display control unit 12d for controlling the display of the display unit 15 are configured to perform drive control of each unit constituting the jitter adding apparatus 1. .

  Examples of display control in the display control unit 12d include display control of the phase modulation amount and modulation frequency for each jitter type displayed on the display unit 15, display control for displaying the set jitter type, for example, for each jitter type Display control for setting the presence / absence of output, the total amount of jitter generation calculated by the total amount calculation unit 12a reaches the jitter generation amount guarantee value 81 and generation amount upper limit value 82 stored in the jitter generation amount storage unit 13. Display control for indicating whether or not it has been performed, display control of a modulation waveform image corresponding to the set jitter type, and the like.

  The jitter adding unit 14 includes, for example, a D / A converter and a phase modulator. For example, the jitter adding unit 14 generates a clock signal or a data signal generated in the jitter adding apparatus 1 and set to an arbitrary rate by the user, or the jitter adding apparatus 1. To the target signal 50, which is a test signal or the like input from an external signal source, is added with jitter having a modulation frequency and phase modulation amount arbitrarily set by the operation unit 10, and a signal having a specified jitter generation amount (jitter (Additional signal). Specifically, D / A conversion is performed on the modulation frequency information and the phase modulation amount information input as a digital signal from the operation unit 10 to generate an analog signal and apply the frequency, amplitude, and phase of the modulation signal to the phase modulator. Is changed, jitter of modulation frequency information and phase modulation amount information set by the operation unit 10 is generated and added to the target signal 50.

  The display unit 15 includes a display device such as an LCD (Liquid Crystal Display), and displays display contents based on the control of the display control unit 12d. The display contents displayed on the display unit 15 include, for example, a phase modulation amount and modulation frequency display column 30a for displaying the phase modulation amount and modulation frequency for each jitter type, as shown in FIG. Jitter output setting item 30b for setting the presence / absence, jitter output display item 30c for displaying the presence / absence of output for each jitter type, and the total amount of jitter generation calculated by the total amount calculation unit 12a are stored in the jitter generation amount storage unit 13. When the jitter generation amount guarantee value 81 has been reached, a display such as “Overload” is displayed on the generation amount guarantee value arrival display 30d. Further, when the total amount of jitter generation calculated by the total amount calculation unit 12a reaches the jitter generation amount upper limit value 82 stored in the jitter generation amount storage unit 13, a display such as “Upper Limit” is generated. It is displayed on the upper limit reaching display 30e. Further, when the target signal 50 is generated inside the jitter adding apparatus 1, the frequency may be displayed on the internal target signal frequency display 30f.

[Processing related to generation amount guarantee value arrival display]
Next, an example of a processing operation related to the generation amount guarantee value arrival display 30d in the jitter adding apparatus 1 described above will be described with reference to FIG. The display configuration shown in FIG. 4 is used as the screen display configuration used when setting and displaying the parameter values.

  In the jitter adding apparatus 1, the user arbitrarily sets a combination of a plurality of jitter types for the jitter signal b generated using the operation unit 10, and arbitrarily sets the modulation frequency and the phase modulation amount for each jitter type. The parameter value for this is set from the operation unit 10.

  For example, when the generated jitter type 80 is “SJ + PJ”, the modulation frequency of “SJ” is set to 5 MHz, the phase modulation amount is set to 10 UI, the modulation frequency of “PJ” is set to 7 MHz, and the phase modulation amount is set to 5 UI.

  Further, the operation unit 10 includes a generated jitter type 80, a modulation amount and phase modulation amount arbitrarily set for each of a plurality of jitter types included in the generated jitter type 80, a total amount calculating unit 12a, and a jitter generated amount storage unit 13 And output to the jitter adding section 14 (ST1).

  Next, the total amount calculation unit 12a outputs a jitter based on a combination of a plurality of arbitrarily set jitter types output from the operation unit 10, and a modulation frequency and a phase modulation amount arbitrarily set for each jitter type. The total amount of generation is calculated and output to the jitter generation amount storage unit 13 (ST2).

  For example, the generated jitter type 80 is “SJ + PJ”, the modulation frequency of “SJ” is set to 5 MHz, the phase modulation amount is set to 10 UI, the modulation frequency of “PJ” is set to 7 MHz, and the phase modulation amount is set to 5 UI. In this case, the total amount of jitter generation is 15 UI which is the sum of 10 UI of “SJ” and 5 UI of “PJ”.

  The jitter adding unit 14 outputs the target signal according to the generated jitter type 80 and the modulation frequency and phase modulation amount arbitrarily set for each of the plurality of jitter types included in the generated jitter type 80. Jitter is added to 50 (ST3).

  Next, the jitter generation amount storage unit 13 outputs the generated jitter type 80 and the modulation frequency and phase modulation amount arbitrarily set for each of the plurality of jitter types included in the generated jitter type 80. Based on the table 20 stored in advance, the generated amount guaranteed value 81 is output to the generated amount guaranteed value determination unit 12b (ST4).

  For example, when the generated jitter type 80 is “SJ + PJ”, the modulation frequency of “SJ” is set to 5 MHz, and the modulation frequency of “PJ” is set to 7 MHz, the generated amount guaranteed value 81 is based on the table shown in FIG. Becomes “12.14 UI (@ 1M-10 MHz)” of “SJ + PJ”.

  Here, when the modulation frequency of any one of the generated jitter types 80 (for example, “PJ”) falls within the range of a plurality of modulation frequencies in the table 20 (for example, modulation) For the frequency 20 MHz), the generation amount guarantee value (“0.85 UI (@ 10M-250 MHz)”) in the high frequency range including the modulation frequency in the table 20 is applied.

  Next, the generation amount guarantee value determination unit 12b compares the total amount of jitter generation output from the total amount calculation unit 12a with whether or not the generation amount guarantee value 81 output from the jitter generation amount storage unit 13 has been reached. The determination is made, and the determination result is output to the display control unit 12d (ST5).

  For example, the generated jitter type 80 is “SJ + PJ”, the generated amount guaranteed value 81 is “12.14 UI (@ 1M−10 MHz)” based on the table 20 stored in advance, and the total amount of jitter generated Since the total amount of jitter generation has reached the generation amount guarantee value 81, the fact that the generation amount has been reached is output to the display control unit 12d as a determination result.

  Next, the display control unit 12d performs control to display whether or not the generation amount guaranteed value 81 has been reached on the display unit 15 based on the determination result output from the generation amount guaranteed value determination unit 12b. The display unit 15 performs display according to control by the display control unit 12d (ST6).

  When the generated amount guarantee value 81 is reached as the display content displayed on the display unit 15, for example, “Overload” is displayed, and voice output, electronic sound, and output to the outside of the jitter adding device 1 are performed. May be.

  As described above, the generation amount guaranteed value 81 is displayed based on the generated jitter type 80 and the modulation frequency and phase modulation amount arbitrarily set for each of the plurality of jitter types included in the generated jitter type 80. Therefore, even when the output value of the jitter generation amount of the jitter adding device reaches the generation amount guarantee value 81, the user can intuitively set the jitter generation amount while continuing the test with the further jitter generation amount. It can be understood that the output value has reached the generation amount guarantee value 81.

[Processing related to generation amount upper limit arrival display]
Next, an example of a processing operation related to the generation amount upper limit arrival display 30e in the jitter adding apparatus 1 described above will be described with reference to FIG.

  Here, each processing from ST11 to ST16 in FIG. 6 corresponds to each processing from ST1 to ST6 in FIG. 5, and the generated amount guaranteed value in the processing operation related to the generated guaranteed amount arrival display 30d. The determination unit 12b is the same operation as the generation amount upper limit determination unit 12c in the processing operation related to the generation amount upper limit arrival display 30e in the present description, and thus description thereof is omitted.

  Further, as the display contents to be displayed on the display unit 15, the generation amount upper limit value based on the generated jitter type 80 and the modulation frequency and phase modulation amount arbitrarily set for each of the plurality of jitter types included in the generated jitter type 80. 82, and when the generation amount upper limit value 82 is reached, display such as “Upper Limit” is performed, and voice output, electronic sound, and output to the outside of the jitter adding apparatus 1 are performed. The same may be said to be performed.

[Processing related to generation amount guarantee value arrival display]
Next, an example of the software processing operation related to the generated amount guaranteed value arrival display 30d will be described with reference to FIG.

  First, the generation value guarantee value 81, which is a value that can guarantee the output value of the generation amount of jitter, is stored in advance as, for example, the table 20 in association with a combination of a plurality of jitter types (S201).

  First, the user arbitrarily sets a combination of a plurality of jitter types for the generated jitter signal b (S202).

  Next, the user arbitrarily sets a jitter generation amount for the generated jitter signal b. That is, for the combination of a plurality of jitter types arbitrarily set in S202, the modulation frequency and the phase modulation amount are arbitrarily set for each jitter type (S203).

  Next, the total amount of jitter generation is calculated based on the modulation frequency and phase modulation amount arbitrarily set for each jitter type (S204).

  Next, referring to the table 20 stored in advance in S201, the generated jitter type 80 and the generated amount corresponding to the modulation frequency and phase modulation amount arbitrarily set for each of the plurality of jitter types included in the generated jitter type 80 The guaranteed value 81 is confirmed (S205).

  Next, using the total amount of jitter generation calculated in S204 and the generation amount guarantee value 81 confirmed in S205, it is compared and determined whether or not the total amount of jitter generation reaches the generation amount guarantee value 81. (S206).

  Next, it is displayed whether or not the generation amount guarantee value 81 has been reached based on the determination result of S206 (S207). When the generation amount guarantee value 81 has been reached, for example, “Overload” may be displayed, and voice output, electronic sound, or output to the outside may be performed.

  As described above, the generation amount guaranteed value 81 is displayed based on the generated jitter type 80 and the modulation frequency and phase modulation amount arbitrarily set for each of the plurality of jitter types included in the generated jitter type 80. Therefore, even when the output value of the jitter generation amount of the jitter adding device reaches the generation amount guarantee value 81, the user can intuitively set the jitter generation amount while continuing the test with the further jitter generation amount. It can be understood that the output value has reached the generation amount guarantee value 81.

[Processing related to generation amount upper limit arrival display]
Next, an example of the software processing operation relating to the generation amount upper limit arrival display 30e will be described with reference to FIG.

  Here, each processing from S208 to S210 in FIG. 8 corresponds to each processing from S201 to S207 in FIG. That is, S201 in FIG. 7 corresponds to S208 in FIG. 8, and S206 in FIG. 7 corresponds to S210 in FIG. As described above, the processing operation related to the generation amount guarantee value arrival display 30d is the same as the processing operation related to the generation amount upper limit arrival display 30e in the present description, and thus description thereof is omitted. Further, based on the generated jitter type 80 and the modulation frequency and phase modulation amount arbitrarily set for each of the plurality of jitter types included in the generated jitter type 80, it is determined whether or not the generated amount upper limit value 82 has been reached. When the generation amount upper limit value 82 has been reached, for example, “Upper Limit” is displayed, and sound output, electronic sound, or output to the outside may be performed.

  In this way, since it is displayed that the generation amount upper limit value 82 has been reached based on the modulation frequency and phase modulation amount arbitrarily set for each jitter type, jitter having various jitter types is generated. Even when the output value of the jitter generation amount of the jitter adding device reaches the generation amount upper limit value 82 of the jitter generation amount, the user intuitively sets the output value of the jitter generation amount to the upper limit value of the generation amount. It is possible to grasp that it has reached 82.

[Processing related to generation amount guaranteed value arrival display and generation amount upper limit arrival display]
Next, an example of the software processing operation related to the generated amount guaranteed value arrival display 30d and the generated amount upper limit value reached display 30e will be described with reference to FIG.

  Here, each process from S201 to S210 in FIG. 9 corresponds to each process from S201 to S210 described in FIGS. 6 and 7, respectively. As described above, the processing operations related to the generated amount guarantee value arrival display 30d and the generated amount upper limit value arrival display 30e are the same as the processing described above, and thus description thereof is omitted. When the generation amount guarantee value 81 is reached, for example, “Overload” may be displayed, and voice output, electronic sound, or output to the outside may be performed. Further, it is determined whether or not the generation amount upper limit value 82 has been reached. If the generation amount upper limit value 82 has been reached, a display such as “Upper Limit” is displayed, and voice output, electronic sound, or external output is displayed. Similarly, output may be performed.

  As described above, the generation amount guaranteed value 81 is displayed based on the generated jitter type 80 and the modulation frequency and phase modulation amount arbitrarily set for each of the plurality of jitter types included in the generated jitter type 80. Therefore, even when the output value of the jitter generation amount of the jitter adding device reaches the generation amount guarantee value 81, the user can intuitively set the jitter generation amount while continuing the test with the further jitter generation amount. It is possible to grasp that the output value has reached the guaranteed amount of generation.

  Furthermore, the generation amount upper limit 82 is displayed based on the generated jitter type 80 and the modulation frequency and phase modulation amount arbitrarily set for each of the plurality of jitter types included in the generated jitter type 80. Therefore, even when the jitter having various jitter types is generated, even when the output value of the jitter generation amount of the jitter adding device reaches the generation amount upper limit 82 of the jitter generation amount, the user intuitively It can be understood that the output value of the jitter generation amount has reached the generation amount upper limit value.

DESCRIPTION OF SYMBOLS 1 ... Jitter addition apparatus 10 ... Operation part 11 ... Jitter classification setting part 12 ... Control part (Total amount calculation part 12a, generation amount guarantee value determination part 12b, generation amount upper limit determination part 12c, display control part 12d)
DESCRIPTION OF SYMBOLS 13 ... Jitter generation amount memory | storage part 14 ... Jitter addition part 15 ... Display part 20 ... Table 30a ... Display column of phase modulation amount and modulation frequency 30b ... Jitter output setting item 30c ... Jitter output display item 30d ... Generation amount guarantee value arrival display 30e ... Generation amount upper limit arrival display 30f ... Internal target signal frequency display 50 ... Target signal 80 ... Generation jitter type 81 ... Generation amount guaranteed value 82 ... Generation amount upper limit value 100 ... Device under test

Claims (8)

In order to add jitter to the target signal (50) to which jitter is to be added, a parameter including the amount of jitter generation is arbitrarily set, and an arbitrary plurality of jitter types can be selected from the jitter type to which the jitter is added. An operation unit (10) for setting a jitter type;
In a jitter adding device (1) comprising a jitter adding unit (14) for adding the jitter,
A jitter generation amount storage unit (13) that stores in advance generation amount guarantee values, which are values that can guarantee the amount of jitter generation, in advance as parameter values in association with the combinations of the plurality of jitter types;
A generation amount guarantee value determination unit (12b) for determining whether or not the arbitrarily set jitter generation amount has reached the generation amount guarantee value stored in the jitter generation amount storage unit; Jitter adding device.   2. The jitter adding apparatus according to claim 1, wherein the parameter value includes at least a total amount of jitter generation corresponding to a modulation frequency that is a phase variation speed of the jitter in the combination of the jitter types.   When the arbitrarily set jitter generation amount reaches the generation amount guarantee value stored in the jitter generation amount storage unit, the display unit (15) displays that the generation amount guarantee value has been reached. The jitter adding apparatus according to claim 1, further comprising a control unit (12 d). In the jitter generation amount storage unit, a generation amount upper limit value, which is an upper limit at which an output value of the jitter generation amount can be generated, is stored in advance as a parameter value corresponding to each combination of the plurality of jitter types,
A generation amount upper limit determination unit (12c) for determining whether or not the arbitrarily set jitter generation amount has reached the generation amount upper limit value stored in the jitter generation amount storage unit;
The display control unit indicates that the generation amount upper limit value is reached when the arbitrarily set jitter generation amount reaches the generation amount upper limit value stored in the jitter generation amount storage unit. The jitter adding apparatus according to claim 3, wherein the jitter adding apparatus is displayed. A jitter type setting step (S202) for setting a plurality of arbitrary jitter types from the jitter type, which is the type to which the jitter is added, in order to add jitter to the target signal (50) to which jitter is to be added;
A jitter addition method including a jitter generation amount setting step (S203) for arbitrarily setting the jitter generation amount;
A jitter generation amount guarantee value storing step (S201) for preliminarily storing as a parameter value a generation amount guarantee value that is a value that can guarantee the output value of the jitter generation amount;
Generation amount guarantee value determination step for determining whether or not the jitter generation amount arbitrarily set in the jitter generation amount setting step has reached the generation amount guarantee value stored in the jitter generation amount guarantee value storage step. And a jitter adding method comprising: (S206).   6. The jitter addition method according to claim 5, wherein the parameter value includes at least a total amount of jitter generation corresponding to a modulation frequency that is a phase fluctuation speed of the jitter in the combination of the jitter types.   7. A guarantee value display step (S207) for displaying that the jitter generation amount arbitrarily set in the jitter generation amount setting step has reached the generation amount guarantee value. The jitter addition method according to any one of the above items. A jitter generation amount upper limit storage step (S208) for preliminarily storing the generation amount upper limit value, which is an upper limit at which an output value of the jitter generation amount can be generated, corresponding to each combination of the plurality of jitter types as a parameter value;
Generation amount upper limit determination step for determining whether or not the jitter generation amount arbitrarily set in the jitter generation amount setting step has reached the generation amount upper limit value stored in the jitter generation amount upper limit value storage step. (S209),
The jitter addition method according to claim 7, further comprising an upper limit value display step (S210) for displaying that the generated amount upper limit value has been reached.

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