JP2002156397A - Spectrum-measuring method, spectrum analyzer and spectrum-measuring system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten measuring time and to surely measure during intermittent operation, without causing a device to be measured which operates intermittently to operates continuously during measurement of a spectrum. SOLUTION: When measuring the spectrum of the device to be measured which operates intermittently at a prescribed cycle, the spectrum is measured by setting sweep time for the spectrum measurement, based on the cycle and time of the intermittent operation. In addition, a repeating times of measurement is set based on a measuring frequency band width, the cycle and time of the intermittent operation, and the spectrum is measured, corresponding to the set sweep time and the number of times of measurement repeated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spectrum measuring method, a spectrum analyzer and a spectrum measuring system, and more particularly to a spectrum measuring method, a spectrum analyzer and a spectrum measuring system for measuring a spectrum of a device under test which is operating intermittently.

[0002]

2. Description of the Related Art Conventionally, when measuring the electromagnetic spectrum of a device under test, a spectrum analyzer (sp
ectrum analyzer). A spectrum analyzer is a measuring device that analyzes the frequency of a signal.
The measured signal is decomposed into frequency components and displayed as an amplitude-frequency relationship. FIG. 9 is an explanatory diagram of the measurement concept of the spectrum analyzer. The spectrum analyzer is a sweep-type measuring device, which sequentially sweeps the frequency band 80 to be measured for each measurement resolution frequency band 81 and obtains the maximum value of the amplitude of the frequency signal 83 to be measured corresponding to the measurement resolution frequency bandwidth 81 or Find the minimum value. The sweep time at this time is represented as that corresponding to the symbol L in FIG. Then, an amplitude-frequency characteristic graph 84 corresponding to the measurement frequency band 80, as shown in FIG.
It is displayed on the display screen of a display device such as a RT (Cathode Ray Tube). In addition, it has a function of repeatedly measuring the same frequency band and updating a maximum value or a minimum value of measurement values measured a plurality of times. By the way, there are the following methods for measuring the electromagnetic spectrum of a device under test that performs an intermittent operation.

[1] First Conventional Example This is a method in which measurement is repeated for a frequency band 80 to be measured and the maximum value of measured values measured a plurality of times is updated, and measurement is repeated for a long time. [2] Second Conventional Example The frequency band 80 to be measured is divided into a plurality of frequency bands, and each divided frequency band is measured for a time corresponding to an intermittent period. [3] Third Conventional Example In order to shorten the measurement time as compared with the first conventional example and the second conventional example, and to ensure that the device under test is operating in the entire measurement frequency band, The intermittent operation of the device under test is stopped, the mode is shifted to the continuous operation mode, and the spectrum is measured by the spectrum analyzer in the continuous operation state.

[0004]

According to the first conventional example, it is not guaranteed that the device under test is operating in all the measurement frequency bands, so that a desired measurement result can be obtained. Is not guaranteed. Further, according to the second conventional example, the entire period of the frequency band 80 to be measured includes a period during which the device under measurement is operating. However, there is a problem that the sweep time of the spectrum analyzer is set long. According to the third conventional example, it is necessary to operate the device under test continuously during measurement, and if the device under test only intermittently operates during normal operation, the continuous operation mode is used only for measurement. It is necessary to provide a mechanism for shifting to the above, and there is a problem that the configuration becomes redundant.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a spectrum measurement system capable of shortening the measurement time and making sure that the measurement can be performed during the intermittent operation without having to make the device under test performing the intermittent operation perform the continuous operation at the time of spectrum measurement. It is to provide a method, a spectrum analyzer and a spectrum measurement system.

[0006]

According to a first aspect of the present invention, there is provided a spectrum measuring method for measuring a spectrum of a device under test which performs an intermittent operation at a predetermined cycle. A sweep time setting step of setting the sweep time L at the time of the spectrum measurement based on the operation time, and a measurement step of performing a spectrum measurement based on the set sweep time L are provided.

According to a second aspect of the present invention, in the configuration of the first aspect, in the sweep time setting step, the cycle of the intermittent operation is T, the operating time in the intermittent operation is M, and When the relationship is satisfied, the sweep time L is calculated and set by the equation (2). T = K × M (K is an integer of 2 or more) (1) L = (K−1) × M (2)

According to a third aspect of the present invention, there is provided a spectrum measuring method for measuring a spectrum of a device under test which performs an intermittent operation at a predetermined cycle, wherein the sweep at the time of the spectrum measurement is performed based on the cycle and the time of the intermittent operation. Sweep time setting process for setting time L, measurement frequency bandwidth,
A repetition number setting step of setting the number of measurement repetitions Y based on the period and the time of the intermittent operation; and a measurement step of performing spectrum measurement based on the set sweep time L and repetition number Y. It is characterized by.

According to a fourth aspect of the present invention, in the configuration of the third aspect, in the sweep time setting step, the cycle of the intermittent operation is T, the operation time in the intermittent operation is M, and N is an arbitrary natural number. In this case, the sweep time L
Is calculated and set. L = T × N−Δt (3) where 0 <| Δt | ≦ M.

According to a fifth aspect of the present invention, in the configuration of the fourth aspect, the step of setting the number of repetitions calculates the minimum value of the number of repetitions Y based on equation (4) or (5). Features. Y = f ((T−M) / Δt) +2 (when the remainder of the fractional expression (T−M) / Δt is not 0) (4) Y = f ((T−M) / Δt) +1 ( When the remainder of the fractional expression (TM) / Δt is 0: (5) where f ((TM) / Δt) is the fractional expression (TM)
/ Δt.

According to a sixth aspect of the present invention, there is provided a spectrum analyzer for performing a spectrum measurement of a device under test that performs an intermittent operation at a predetermined cycle, wherein the sweep time at the time of the spectrum measurement is based on the cycle and the time of the intermittent operation. It is characterized by comprising a sweep time setting unit for setting L, and a measuring unit for performing spectrum measurement based on the set sweep time L.

According to a seventh aspect of the present invention, in the configuration of the sixth aspect, the sweep time setting unit sets a cycle of the intermittent operation to T, sets an operation time in the intermittent operation to M,
When the relationship of Expression (1) is satisfied, the sweep time L is calculated and set by Expression (2). T = K × M (K is an integer of 2 or more) (1) L = (K−1) × M (2)

In a spectrum analyzer for performing a spectrum measurement of a device under test that performs an intermittent operation at a predetermined cycle, the sweep time at the time of the spectrum measurement is based on the cycle and the time of the intermittent operation. A sweep time setting unit for setting L, a measurement frequency bandwidth,
A repetition number setting unit that sets the number of measurement repetitions Y based on the period and the time of the intermittent operation; and a measurement unit that performs spectrum measurement based on the set sweep time L and the number of repetitions Y. It is characterized by.

According to a ninth aspect of the present invention, in the configuration of the eighth aspect, the sweep time setting section sets the cycle of the intermittent operation to T, sets the operation time in the intermittent operation to M, and sets N to any natural number. In this case, the sweep time L is calculated and set by the equation (3). L = T × N−Δt (3) where 0 <| Δt | ≦ M.

According to a tenth aspect of the present invention, in the configuration of the ninth aspect, the repetition number setting unit calculates the minimum value of the number of repetitions Y based on the equation (4) or (5). Features. Y = f ((T−M) / Δt) +2 (when the remainder of the fractional expression (T−M) / Δt is not 0) (4) Y = f ((T−M) / Δt) +1 ( When the remainder of the fractional expression (TM) / Δt is 0: (5) where f ((TM) / Δt) is the fractional expression (TM)
/ Δt.

According to another aspect of the present invention, there is provided a spectrum measuring system for performing a spectrum measurement of a device under test that performs an intermittent operation at a predetermined period by using a spectrum analyzer. An external control device for setting the operation time of the device, and a sweep time L at the time of the spectrum measurement is set for the spectrum analyzer based on the period of the intermittent operation and the operation time of the intermittent operation set by the external control device. And a control instruction device.

According to a twelfth aspect of the present invention, in the configuration of the eleventh aspect, the control instruction device is configured to determine, based on a measured frequency bandwidth, the period, and the time of the intermittent operation,
It is characterized in that the number of measurement repetitions Y is set for the spectrum analyzer.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a preferred embodiment of the present invention will be described with reference to the drawings. [1] First Embodiment First, a first embodiment will be described. FIG. 1 shows a schematic configuration block diagram at the time of measurement. Spectrum analyzer 10
Is connected to the device under test 20 that performs an intermittent operation. In this case, the spectrum analyzer 10
Shall be repeatedly measured while updating the maximum value of the spectrum of the measurement frequency band.

FIG. 2 shows a schematic configuration diagram of the spectrum analyzer. FIG. 2 is a schematic configuration diagram of a real-time spectrum analyzer. Spectrum analyzer 10
Represents an input terminal 11 and a plurality of bandpass filter units 12
-1 to 12-n, a plurality of peak detectors 13-1 to 13-n,
It is provided with a high-speed changeover switch 14, a sweep signal generator 15, and a display 16. A plurality of band pass filter units are connected in parallel to the input terminal. Each band-pass filter unit 12-1 to 12-n is set so that the pass bandwidths overlap each other, and the pass bandwidth of all the band-pass filter units 12-1 to 12-n is the measurement target. It is designed to be equal to the frequency bandwidth. The peak detectors 13-1 to 13-n detect peak values (maximum values or minimum values) of the output signals of the corresponding band-pass filter units 12-1 to 12-n, and hold the updated values. The high-speed changeover switch 14 sequentially switches the output signal of any one of the peak detectors 13-1 to 13-n and outputs the output signal to the display unit 16 under the control of the sweep signal generator 15. The display unit 16 displays the relationship between the amplitude and the frequency of the input signal (measured signal) based on the output signal from the high-speed switch 14. Next, the operation will be described.

FIG. 3 is a diagram for explaining the operation of the device under test. The device under test 20 operates every intermittent operation cycle T, and its operation time is M. Thereby, the intermittent operation cycle T
Each time, the spectrum is observed only during the operation time M. In this case, the sweep time for the measurement frequency band is L, and T = K × M (K is an integer of 2 or more) (1) L = (K−1) × M (2) If it can be satisfied, measurement can be performed efficiently. More specifically, the case where K = 5 will be described with reference to FIG. In this case, T = 5 × ML = (5-1) × M = 4 × M. In this case, since the sweep time L is a period four times as long as the operation time M, the measurement frequency band is divided into four frequency bands (low band 6, middle low band 7, middle high band 8, high band 9), and four times. This completes the measurement of the measurement frequency band. In the example of FIG. 4, the operation start time of the device under test and the sweep start time (time t0) coincide with each other. If the operation start time deviates, the measurement frequency band is measured by 4 + 1 = 5 measurements. Will be completed. Similarly, the sweep time L is equal to the operation time M
In this case, the measurement of the measurement frequency band is completed with a maximum of X + 1 measurements. That is, the first
During the first sweep operation, which is the second measurement, since the device under measurement 20 is operating during the sweep start time t0 to the time t1 (= t0 + M), the sweep start time t0 to t0
During the period of time t1, the measurement of the frequency band of the low band 6 is performed.
Then, by performing the time axis-frequency axis conversion of the measurement result, the actual measurement result is as shown in FIG.

Subsequently, at the time of the second sweep operation, which is the second measurement, from time t1 to time t2 (= t0 + 2 ·
Since the device under measurement 20 is operating during the period of M),
During the period from the sweep start time t1 to the time t2, the measurement of the frequency band of the middle / low range 7 is performed. And the time axis of the measurement result-
By performing the frequency axis conversion, the actual measurement result at the time of completion of the second measurement is as shown in FIG. 5B. Next, during the third sweep operation, which is the third measurement, since the device under measurement 20 is operating during the period from time t2 to time t3 (= t0 + 3 · M), the sweep start time t2 During the period of time t3, the measurement of the frequency band of the middle-high band 8 is performed. Then, by performing the time axis-frequency axis conversion of the measurement result, the actual measurement result at the time of completion of the third measurement is as shown in FIG. 5C. Subsequently, in the fourth sweep operation, which is the fourth measurement, since the device under measurement 20 is operating during the period from time t3 to time t4 (= t0 + 4 · M), the sweep start time t3 to During the period of time t4, the frequency band of the high frequency band 9 is measured. Then, by performing the time axis-frequency axis conversion of the measurement result, the actual measurement result at the time of completion of the fourth measurement is as shown in FIG.
The measurement is completed over the entire measurement frequency band.

[2] Second Embodiment Next, a second embodiment will be described with reference to FIG. In the first embodiment, the case where the intermittent cycle T is an integral multiple of 2 or more of the operating time M has been described. However, the actual intermittent cycle T does not always satisfy the relationship with the operating time M. . Therefore, the second embodiment provides a more practical measurement method. In the second embodiment,
Since the device configuration is the same as that of the first embodiment, it will be described with reference to FIGS. FIG. 6 shows an operation explanatory diagram of the second embodiment. The period of the intermittent operation of the device under test 20 is T, the operation time in the intermittent operation is M, N is an arbitrary natural number, and Δt is a parameter. In this case, as in the first embodiment, it is assumed that the spectrum is observed only during the operation time M for each cycle T.

In this case, the sweep time for the measurement frequency band is L, and the sweep time is such that L = T × N−Δt (3) 0 <| Δt | ≦ M (4) Set L. More specifically, a case where N = 2 and 0 <Δt ≦ M5 will be described with reference to FIG. In this case, the minimum number of measurement repetitions Y required for measurement can be expressed by equation (5) or equation (6). In the following description, Z is a fractional expression, and f (Z) represents a quotient of the fractional expression. Y = f ((T−M) / Δt) +2 (when the remainder of the fraction formula Z is not 0) (5) Y = f ((T−M) / Δt) +1 (the remainder of the fraction formula Z is 0) ............ (6)

As described above, by setting the number Y of measurement repetitions, the measurement is completed over the entire measurement frequency band. Therefore, the time for completing the measurement of the measurement frequency band requires Y × L times. In this case, the settable time Δt
Is set as large as possible, the number of measurement repetitions Y can be reduced, and the time (= Y × L) for completing the measurement of the measurement frequency band can be shortened. According to the above configuration, as shown in FIG.
Can be measured once or plural times during the sweep time L while shifting the relative time of the operation time of the device under test by Δt, as shown in FIGS. 7A to 7D. Then, the measurement within the measurement frequency band can be sequentially performed, and the measurement is finally completed over the entire measurement frequency band.

[3] Third Embodiment In each of the above embodiments, the intermittent operation cycle T and the operation time M of the device under test are fixed. However, in the third embodiment, the intermittent operation of the device under test is performed. Period T and operating time M
Is an embodiment in the case of a device under test in which can be set externally. FIG. 8 shows a schematic configuration block diagram of a spectrum measurement system according to the third embodiment. The spectrum measurement system 50 includes a device under test 51 and a spectrum analyzer 5.
2, an external control device 53, and a control instruction device 54. The device under test 51 sets an intermittent operation cycle T and an operation time M based on a control signal A from the external control device 53, and operates based on the set intermittent operation cycle and operation time M. The control instruction device 54 includes a reception unit 55, a control unit 56, a calculation unit 57, and a transmission unit 58
And is provided.

The receiving section 55 receives the control signal A and outputs it to the calculating section 57. The control unit 56 controls the calculation unit 57. The calculation unit 57 controls the control signal A under the control of the control unit 56.
The optimum sweep time L and the number of measurement repetitions Y for the intermittent operation cycle T and operation time M corresponding to
8 is output. As a result, the transmission unit 58 outputs the control signal B for setting the input sweep time L and the number of measurement repetitions Y to the spectrum analyzer 52. The spectrum analyzer 52 performs measurement based on the sweep time L and the number of measurement repetitions Y corresponding to the control signal B. The specific measurement is the same as in the first embodiment or the second embodiment.

[4] Effects of the Embodiments According to the above embodiments, it is not necessary to implement the continuous operation mode only for the measurement in the device to be measured, so that the circuit configuration or the device configuration can be simplified and the manufacturing can be simplified. Cost can also be reduced. Further, the measurement time can be optimized, and the measurement time can be substantially reduced. Further, the operation time of the device to be measured is surely included in the sweep time, and a desired measurement result can be reliably obtained.

[0028]

According to the present invention, the measurement time can be optimized, and the measurement time can be substantially reduced. In addition, the operation time of the device to be measured is reliably included in the sweep time, and a desired measurement result can be reliably obtained. Further, in the device under test, it is not necessary to implement the continuous operation mode only for the measurement, so that the circuit configuration or the device configuration can be simplified and the manufacturing cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a schematic configuration block diagram at the time of measurement according to a first embodiment.

FIG. 2 is a schematic configuration diagram of a spectrum analyzer.

FIG. 3 is an explanatory diagram of the operation of the device under test.

FIG. 4 is an explanatory diagram of a specific measurement operation in the first embodiment.

FIG. 5 is an explanatory diagram of a specific measurement result in the first embodiment.

FIG. 6 is an explanatory diagram of a specific measurement operation in the second embodiment.

FIG. 7 is an explanatory diagram of a specific measurement result in the second embodiment.

FIG. 8 is a schematic configuration block diagram of a spectrum measurement system according to a third embodiment.

FIG. 9 is an explanatory diagram of a measurement concept of the spectrum analyzer.

FIG. 10 is an explanatory diagram of a display example of an amplitude-frequency characteristic graph corresponding to a measurement frequency band.

[Explanation of symbols]

 10, 52: Spectrum analyzer 20, 51: Device under test 11: Input terminal 12-1 to 12-n: Bandpass filter unit 13-1 to 13-n: Peak detection unit 14: High-speed switch 15: Sweep signal generation Unit 16: Display unit 53: External control device 54: Control instruction device 55: Receiving unit 56: Control unit 57: Calculation unit 58: Transmission unit

Claims (12)

[Claims] 1. A spectrum measuring method for performing a spectrum measurement of a device under test that performs an intermittent operation at a predetermined cycle, comprising: setting a sweep time L at the time of the spectrum measurement based on the cycle and the time of the intermittent operation. A spectrum measuring method, comprising: a time setting step; and a measuring step of performing spectrum measurement based on a set sweep time L. 2. The spectrum measuring method according to claim 1, wherein in the sweep time setting step, the cycle of the intermittent operation is T, the operating time in the intermittent operation is M, and the relationship of the formula (1) is satisfied. In this case, the sweep time L
Calculating and setting the spectrum. T = K × M (K is an integer of 2 or more) (1) L = (K−1) × M (2) 3. A spectrum measuring method for performing a spectrum measurement of a device under test that performs an intermittent operation at a predetermined period, wherein a sweeping time L at the time of the spectrum measurement is set based on the period and the time of the intermittent operation. A time setting step, a repetition number setting step of setting a measurement repetition number Y based on the measurement frequency bandwidth, the period and the intermittent operation time, and a spectrum measurement based on the set sweep time L and the repetition number Y. And a spectrum measuring method, comprising: 4. The spectrum measuring method according to claim 3, wherein in the sweep time setting step, when a cycle of the intermittent operation is T, an operation time in the intermittent operation is M, and N is an arbitrary natural number, 3) A spectrum measuring method, wherein a sweep time L is calculated and set according to equation (3). L = T × N−Δt (3) where 0 <| Δt | ≦ M. 5. The spectrum measuring method according to claim 4, wherein the step of setting the number of repetitions is performed by using equation (4) or (5).
A spectrum measuring method, wherein a minimum value of the number of repetitions Y is calculated based on an equation. Y = f ((T−M) / Δt) +2 (when the remainder of the fractional expression (T−M) / Δt is not 0) (4) Y = f ((T−M) / Δt) +1 ( When the remainder of the fractional expression (TM) / Δt is 0: (5) where f ((TM) / Δt) is the fractional expression (TM)
/ Δt. 6. A spectrum analyzer for performing a spectrum measurement of a device under test that performs an intermittent operation at a predetermined cycle, wherein a sweep time for setting a sweep time L at the time of the spectrum measurement based on the cycle and the time of the intermittent operation. A spectrum analyzer, comprising: a setting unit; and a measurement unit that performs spectrum measurement based on a set sweep time L. 7. The spectrum analyzer according to claim 6, wherein the sweep time setting unit sets a cycle of the intermittent operation to T,
A spectrum analyzer, wherein the operating time in the intermittent operation is M, and when the relationship of the expression (1) is satisfied, the sweep time L is calculated and set by the expression (2). T = K × M (K is an integer of 2 or more) (1) L = (K−1) × M (2) 8. A spectrum analyzer for performing a spectrum measurement of a device under test that performs an intermittent operation at a predetermined cycle, wherein a sweep time for setting a sweep time L at the time of the spectrum measurement based on the cycle and the time of the intermittent operation. A setting unit, a repetition number setting unit that sets the number of measurement repetitions Y based on the measurement frequency bandwidth, the period, and the time of the intermittent operation; and a spectrum measurement based on the set sweep time L and repetition number Y. A spectrum analyzer, comprising: a measurement unit for performing measurement; 9. The spectrum analyzer according to claim 8, wherein the sweep time setting unit sets (3) when a cycle of the intermittent operation is T, an operation time in the intermittent operation is M, and N is an arbitrary natural number. A spectrum analyzer which calculates and sets the sweep time L according to the following equation: L = T × N−Δt (3) where 0 <| Δt | ≦ M. 10. The spectrum analyzer according to claim 9, wherein the number-of-repetitions setting unit calculates a minimum value of the number of repetitions Y based on Expression (4) or (5). . Y = f ((T−M) / Δt) +2 (when the remainder of the fractional expression (T−M) / Δt is not 0) (4) Y = f ((T−M) / Δt) +1 ( When the remainder of the fractional expression (TM) / Δt is 0: (5) where f ((TM) / Δt) is the fractional expression (TM)
/ Δt. 11. A spectrum measurement system for performing spectrum measurement of a device under test that performs an intermittent operation at a predetermined cycle using a spectrum analyzer, wherein a period of the intermittent operation of the device under test and an operation time of the intermittent operation are set. An external control device, and a control instruction device for setting the sweep time L at the time of the spectrum measurement to the spectrum analyzer based on the period of the intermittent operation and the operation time of the intermittent operation set by the external control device. A spectrum measurement system, comprising: 12. The spectrum measurement system according to claim 11, wherein the control instruction device sets a measurement repetition count Y to the spectrum analyzer based on a measurement frequency bandwidth, the cycle, and a time of the intermittent operation. A spectrum measurement system characterized in that: