CN104808056A - Frequency characteristic testing method and device based on comparator conversion - Google Patents
Frequency characteristic testing method and device based on comparator conversion Download PDFInfo
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Abstract
The invention discloses a frequency characteristic testing method and device based on comparator conversion. The device comprises a frequency characteristic measurement module, a signal source generation module and an MCU control input and display module. The frequency characteristic measurement module is composed of a D/A converter and a voltage comparator. The method includes the steps of converting an input signal and an output signal of a tested network into square waves through D/A control, measuring signal peak values through the combination with the D/A amplitude seeping technology so as to obtain amplitude-frequency characteristics, and obtaining phase-frequency characteristics through zero comparator conversion and by measuring the rising edge time difference of the two square waves. Compared with a traditional method frequency sweeper and a traditional network analyzer, the frequency characteristic testing method and device have the advantages that the circuit structure is simple, no high-speed AD converters need to be used, the frequency upper limit is not influenced by processors and AD converters, the power consumption is low, portability is achieved, and cost is low; the frequency characteristic testing method and device can be widely applied to measurement of circuit frequency characteristics in the industrial design.
Description
Technical field
The present invention relates to digital circuit technique, signal transacting and automatically control the crossing domains such as detection, being specifically related to a kind of frequency characteristic test method and apparatus with the conversion of device based on the comparison of the advantages such as low cost height frequency range.
Background technology
Traditional frequency characteristic measurement method is on the Frequency point of a series of regulation, point-to-point measurement network gain and phase offset, thus determines amplitude-versus-frequency curve and phase characteristic curve.Although this Method And Principle is simple, the equipment of needs is also uncomplicated.But owing to wanting point-to-point measurement, complex operation is time-consuming, and discontinuous due to frequency-distributed, be very easy to omit some characteristic catastrophe point, and these catastrophe points are usually the problems that we pay special attention to when testing and analysis circuit characteristic.Special sweep generator, as HAD-1252 etc., can only measure amplitude versus frequency characte mostly, seldom has the function measuring phase-frequency characteristic, can not be connected the data needed for deriving, bring a lot of inconvenience to user with computing machine.And not only price is very expensive to meet the digital frequency-characteristic measuring-testing instrument of above-mentioned requirements, and volume is heavy, and such as SP3060 digit synthesis sweep generator, price is more than 10,000, and weight 6kg, is difficult to meet commercial production demand.
Along with the development of modern electronic technology, frequency-characteristic measuring-testing instrument is constantly to miniaturization, and digitizing, intelligent direction develops, based on DDS(Digital Frequency Synthesize) frequency-sweep measuring method of technology has better performance.Except the automatic measurement that can realize network, classic method medium frequency point can also be prevented discrete and omit the problem of details, and what obtain is the dynamic frequency characteristic of circuit-under-test, more realistic application.
Having on the market at present comprises based on zero intermediate frequency quadrature demodulation (Gu Guanghua, Yang Wanlin. digital intermediate frequency quadrature demodulator and FPGA thereof realize. mobile communication, Mobile Communications, the S3 phase in 2004), (Zhou Yang is detected based on real effective, disabled soldier, Liu Shuncheng, Xiang Changhong, Li Peng. the technical research [J] of digital control amplitude versus frequency characte tester. electronic technology. 2013 (05)) method of equifrequent feature measurement, the present invention proposes a kind of frequency characteristic test method and apparatus of the conversion of device based on the comparison completely newly, compared with other existing method, there is circuit structure simple, miniaturization, cost is low, and effectively can improve the advantages such as institute's measured frequency upper limit.
Summary of the invention
In order to overcome expensive, the awkward problem of above-mentioned mentioned legacy frequencies characteristic tester, the present invention proposes the frequency characteristic test method and apparatus of a kind of device based on the comparison conversion, width commercial measurement amplitude versus frequency characte is swept in conjunction with D/A by comparer, zero-crossing comparator converted measurement phase-frequency characteristic, thus method that is simple by equipment, low cost realizes the measurement of frequency characteristic, and keep enough precision, to meet the demand of vast application.
Object of the present invention is at least achieved through the following technical solutions.
A frequency characteristic test device for device conversion based on the comparison, it comprises frequency characteristic measurement module, signal source generation module, MCU control inputs and display module; Described frequency characteristic measurement module is made up of two groups of D/A converters and voltage comparator, be respectively used to the input and output signal measuring tested network, voltage comparator is responsible for surveyed sine wave to be converted into square wave, the numerical information amplitude of sine wave and phase information being converted to square wave sends into MCU process again, D/A converter is controlled by MCU, as an input end of the reference voltage access voltage comparator of voltage comparator, in order to make wider range of survey frequency, voltage comparator needs the model adopting high bandwidth and high pressure Slew Rate; Described signal source generation module is made up of Direct Digital Synthesizer DDS and power amplifier, and DDS is controlled by MCU, and the output of DDS accesses the input end of tested network after the amplification of power amplifier; Described MCU control inputs and display module comprise MCU, external input part and LCD display, user arranges swept frequency range, stepping, model selection by external input part, MCU is according to the output arranging control DDS frequency sweep and D/A, and the output of voltage comparator is processed, result is presented at above LCD display.
The frequency characteristic test method utilizing the device based on the comparison of described device to change, comprises the steps:
User arranges swept frequency range, stepping, model selection by outside input; The frequency needing to measure is calculated according to the input MCU of user; According to the difference of model selection, enter amplitude versus frequency characte test pattern or phase-frequency characteristic test pattern; After entering corresponding modes, MCU control DDS frequency sweep exports each frequency needing to measure, and the corresponding amplitude of measurement on each frequency or phase differential; On LCD, frequency characteristic curve diagram is drawn, display measurement result according to test result.
Further, in above-mentioned method of testing, realize sinusoidal wave peak-value detection method by voltage comparator in conjunction with described D/A converter, measure input, output voltage to obtain the amplitude versus frequency characte of tested network; Adopt improve input, sine wave output signal are converted into square wave by zero-crossing comparator and the method measuring two square wave edge time differences obtains the phase-frequency characteristic of tested network, wherein, the mathematical expectation of mistiming t is made to equal actual value by the randomness of the rising edge to time that control first square wave, repetitive measurement mistiming t is also averaged to make the value of gained mistiming close to its mathematical expectation, i.e. the actual value of time to approach difference.
Further, in above-mentioned method of testing, described sinusoidal wave peak-value detection method comprises: calibrated by later stage correction detecting the error that needed for edge change, minimum pulse width causes due to MCU; Sweep width by the mode of binary search and improve measuring speed.
Further, in above-mentioned method of testing, the described error caused the required minimum pulse width of MCU detection edge change is revised by the later stage the concrete calibration steps calibrated and is: according to sine wave period T, the peak value U1 recorded, the minimum pulse width t that MCU can detect, obtaining the sinusoidal wave peak value after calibrating is U=U1/ sin [(1/2-t/T) * π].
Further, in above-mentioned method of testing, the concrete methods of realizing that the described mode by binary search sweeps width raising measuring speed is: D/A converter is first measured from the intermediate value of span, if it is too low to record value, D/A converter using intermediate value to the interval of maximal value as new span, if it is too high to record value, minimum value to the interval of intermediate value as new span, continues to carry out binary search according to same determination methods by D/A.
Further, in above-mentioned method of testing, the described mode by binary search sweeps width specifically, D/A converter is first measured from the intermediate value of span, as occurred, negative edge illustrates that value is too low, intermediate value is proceeded binary search to the interval of maximal value as new span by D/A converter, and if do not occurred, negative edge illustrates that value is too high, and minimum value is proceeded binary search to the interval of intermediate value as new span by D/A converter.
Further, in above-mentioned method of testing, in the method for measurement two the square wave edge time differences improved, the concrete methods of realizing that the rising edge of described control first square wave makes the mathematical expectation of mistiming t equal actual value to the randomness of time is: control DDS random delay setting-up time starts to export again, rising edge is obeyed time of arrival and is uniformly distributed to make the mathematical expectation of mistiming to equal actual value.
Below again principle of the present invention is described.
Frequency characteristic test mainly comprises the measurement of two aspects: amplitude versus frequency characte is measured and phase-frequency characteristic is measured, and wherein amplitude versus frequency characte represents the relation of increase and decrease with signal frequency of gain, and phase-frequency characteristic represents the phase distortion relation under unlike signal frequency.Therefore, the frequency characteristic of a circuit be measured, can by measure the input of each frequency circuit, the voltage of output signal, and input, output signal phase differential realize.The present invention is by using voltage comparator and D/A(digital to analog converter) voltage that the peak detection circuit that forms is measured input, outputed signal, control DDS sweep measurement can obtain the amplitude versus frequency characte of circuit; Control D/A output voltage is zero, voltage comparator is become zero-crossing comparator, the phase differential of input/output signal can be converted into the rising edge of square wave or the mistiming of negative edge, the phase differential that control DDS frequency sweep records each frequency can obtain the phase-frequency characteristic of circuit.
Compared with prior art, tool of the present invention has the following advantages and technique effect:
1., owing to employing the technology of comparer conversion, do not need offset of sinusoidal ripple itself to carry out collection and FFT computing, eliminate high-speed a/d (analog to digital converter) and DSP(digital signal processor), circuit structure is simple, greatly reduces cost, reduces volume;
2., because the upper limit of survey frequency depends on the speed of comparer, have nothing to do with D/A speed, and the response speed of high-speed comparator itself can reach psec (10
-12second) response of rank, the measurement of 100,000,000 frequency ranges therefore can be realized on the basis of low cost;
3., because the main devices used is if the power consumption such as MCU, comparer is all at below 50mW, therefore entire system power consumption is very low, can control at below 1W and adopt powered battery scheme, greatly improving portability.
Accompanying drawing explanation
Fig. 1 is the frequency characteristic test device schematic diagram of device conversion based on the comparison.
Fig. 2 is the schematic diagram that D/A sweeps the sinusoidal wave peak value of width commercial measurement.
Fig. 3 is the schematic diagram of measurement two sine wave phase differences.
Fig. 4 is the schematic diagram improving time difference measurements precision methods.
Fig. 5 is frequency characteristic test method flow diagram.
Embodiment
Below in conjunction with accompanying drawing, specific embodiment of the invention is described further, but enforcement of the present invention and protection are not limited thereto.
As Fig. 1, the frequency characteristic test device of device conversion based on the comparison, mainly comprises frequency characteristic measurement module, signal source generation module, MCU(micro-control unit) control inputs and display module.Described frequency characteristic measurement module is made up of D/A converter and voltage comparator, both are all double, be respectively used to the input and output signal measuring tested network, voltage comparator is responsible for surveyed sine wave to be converted into square wave, the numerical information amplitude of sine wave and phase information being converted to square wave is sent into MCU again and is carried out processing (disposal route is shown in concrete steps below), D/A converter is controlled by MCU, as an input end of the reference voltage access comparer of voltage comparator, in order to make wider range of survey frequency, voltage comparator needs the model adopting high bandwidth and high pressure Slew Rate, described signal source generation module is by DDS(Direct Digital Synthesizer) and power amplifier form, DDS is controlled by MCU, exports the input end accessing tested network after the amplification of power amplifier, described MCU control inputs and display module are made up of MCU controller, external input part and LCD display, user arranges swept frequency range, stepping, model selection etc. by outside input, MCU is according to the output arranging control DDS frequency sweep and D/A, and the output of voltage comparator is processed, result is presented at above LCD display.
The frequency characteristic test method of the conversion of device based on the comparison that the present invention proposes comprises the following steps:
1. user arranges swept frequency range, stepping, model selection etc. by outside input;
2. the frequency needing to measure is calculated according to the input MCU of user;
3., according to the difference of model selection, system enters
amplitude versus frequency characte test patternor
phase-frequency characteristic test pattern;
4., after entering corresponding modes, MCU control DDS frequency sweep exports each frequency needing to measure, and the corresponding amplitude of measurement on each frequency or phase differential;
5. on LCD, draw frequency characteristic curve diagram according to test result, display measurement result.
Wherein, amplitude versus frequency characte test pattern concrete steps are as follows:
1. each is needed to the frequency of measurement, MCU control DDS exports corresponding frequency, accesses tested network after the amplification of power amplifier.The input of tested network, output signal and be converted corresponding square wave through comparer, send in MCU;
2.MCU control D/A carries out sweeping width, a negative edge can be produced at the output terminal of comparer when the amplitude of D/A just equals sinusoidal wave peak value, therefore when just there is negative edge in comparer the output voltage values of D/A be exactly survey sinusoidal wave peak value, just can record the amplitude of the input of tested network, output terminal sine wave in this approach, also just obtain the gain A v at this frequency;
3.MCU, only after low level certain time, just can detect negative edge, and the concrete time is relevant with MCU technique used.Therefore, when MCU detects negative edge, the output amplitude of D/A is not just equal sinusoidal wave peak value, but is slightly less than sinusoidal wave peak value.In order to reduce error, need to calibrate measurement result, if the amplitude recorded is U
1, sine wave period is the minimum pulse width that T, MCU can detect is t, then the amplitude after calibration should be U=U
1/ sin [(1/2-t/T) * π];
4. in order to improve measuring speed, the mode that D/A sweeps width is that dichotomy sweeps width, namely D/A first measures from the intermediate value of span, as occurred, negative edge illustrates that value is too low, intermediate value is proceeded binary search to the interval of maximal value as new span by D/A, if do not occurred, negative edge illustrates that value is too high, and minimum value is proceeded binary search to the interval of intermediate value as new span by D/A, by that analogy;
5.MCU control DDS carries out frequency sweep, records the gain of each frequency, can obtain the amplitude-versus-frequency curve of tested network.
Phase-frequency characteristic test pattern concrete steps are as follows:
1. measure identical with amplitude versus frequency characte, each is needed to the frequency of measurement, MCU control DDS exports corresponding frequency, after power amplifier amplifies, access tested network.The input of tested network, output signal and be converted corresponding square wave through comparer, send in MCU;
2.MCU control D/A output voltage is zero, makes comparer be operated in Zero-cross comparator state, and output duty cycle is the square wave of 50%;
3. after zero-crossing comparator, sinusoidal wave phase information is converted into the rising edge of two square waves or the mistiming of negative edge, MCU is by timer capture two square wave rising edges, value according to timer can calculate the mistiming, in conjunction with ongoing frequency, the phase differential of input, sine wave output can be obtained;
The measuring accuracy of 4.MCU mainly limits by the frequency of operation of timer, in order to improve measuring accuracy, when obeying being uniformly distributed of 0 to one clock period time of arrival according to rising edge, the mathematical expectation of mistiming equals the principle of actual value, before each Measuring Time difference, control DDS random delay a period of time starts to export again, rising edge obedience time of arrival is made to be uniformly distributed to make the mathematical expectation of mistiming to equal actual value, measure the repeatedly mistiming to average and it can be made close to mathematical expectation, namely close to actual value;
5.MCU control DDS carries out frequency sweep, records the phase differential of each frequency, is described below the phase-frequency characteristic curve that can obtain tested network in conjunction with instantiation again.Fig. 5 is overall flow figure.First, user by outside input arrange frequency sweep bound f
1, f
2with stepping f
0, and select the mode of operation of needs: amplitude versus frequency characte test pattern and phase-frequency characteristic test pattern.MCU enters corresponding pattern according to the setting of user, and control DDS is from f
1start with f
0for stepping frequency sweep, on each frequency, according to the corresponding numerical value of the different measuring of mode of operation, that measure for amplitude versus frequency characte test pattern is input, the output voltage U of tested network
1, U
2, obtaining corresponding gain is: Av=U
2÷ U
1; That measure for phase-frequency characteristic test pattern is the mistiming t of two square wave rising edges, and in conjunction with current institute measured frequency f, can obtain corresponding phase differential is: θ=t*f*2 π.DDS frequency sweep is to highest frequency f
2after, the data of gained and corresponding frequency are combined and is depicted as frequency characteristic curve diagram.
Amplitude versus frequency characte test pattern:
Shown in the structure drawing of device of reference Fig. 1, first the input of tested network, output terminal are received respectively "-" end of a voltage comparator, in "+" termination of comparer, a D/A controlled by MCU as the reference voltage, then System's composition peak detection circuit.MCU control D/A carries out sweeping width, and when the voltage amplitude that D/A exports is greater than sinusoidal wave peak value, comparer exports as high level; When the voltage amplitude that D/A exports is less than or equal to sinusoidal wave peak value, with reference to Fig. 2, comparer exports and there will be negative edge, and the voltage amplitude of D/A is less, and the time that low level maintains is longer.Therefore, when the voltage amplitude of D/A is reduced to the peak value just equaling sine wave, comparer can export an extremely short low level pulse, when MCU detects this pulse, illustrate that the magnitude of voltage of now D/A is exactly sinusoidal wave peak value, the voltage amplitude at tested network two ends can be recorded by this method, thus calculate the voltage gain under ongoing frequency.
Can be seen by Fig. 2, the method has certain error when measuring amplitude.MCU, only after low level certain time, just can detect negative edge, and the concrete time is relevant with MCU technique used, and the minimum pulse width that such as STM32 can detect is 10ns.Therefore, when MCU detects negative edge, the output amplitude of D/A is not just equal sinusoidal wave peak value, but is slightly less than sinusoidal wave peak value.
Suppose, sine wave period is T, and peak value is the minimum pulse width that U, MCU can detect is t, then the last measured amplitude of MCU is U*sin [(1/2-t/T) * π].If to survey sine wave freuqency be the minimum pulse width that 10MHz, MCU can detect is 10ns, then the amplitude recorded is 0.95U, and error is 5%.In order to reduce error, need to calibrate measurement result, if the amplitude recorded is U
1, then the amplitude after calibration should be U=U
1/ sin [(1/2-t/T) * π].
After eliminating this error, main measuring error is the precision of D/A and the input offset voltage (Offset Voltage) of voltage comparator, if select 12 D/A output accuracies to be 1mV, the input offset voltage maximal value of voltage comparator is 4mV, as long as choose suitable chip and in conjunction with peripheral circuit, be the measured signal of about 1V for peak value, can, by control errors below 0.5%, be enough to meet actual requirement.
Sweep width mode about D/A, the simplest implementation sweeps width from high to low, and D/A amplitude when negative edge appears in first time is exactly surveyed peak value.But each D/A amplitude changes all needs some time, add the time waited for needed for negative edge, the measurement of each D/A numerical value needs many time.If the D/A used is 10, then need the D/A numerical value measured to have 2^10=1024, the time of each D/A numerical measuring is 5us, and the frequency of measurement is 200, then the time needed for a sweep measurement is about 1 second, and speed is too slow, cannot realize kinetic measurement.In order to improve measuring speed, D/A sweeps width mode and can adopt binary search, namely D/A first measures from the intermediate value of span, as occurred, negative edge illustrates that value is too low, intermediate value is proceeded binary search to the interval of maximal value as new span by D/A, if do not occurred, negative edge illustrates that value is too high, and minimum value is proceeded binary search to the interval of intermediate value as new span by D/A, by that analogy.For the D/A of 10, use dichotomy to need the D/A numerical value measured to be only 10, the time under the same conditions needed for a sweep measurement is only 10 milliseconds, and this speed is enough to realize kinetic measurement.
Phase-frequency characteristic test pattern:
The hardware that this mode of operation uses is identical with amplitude versus frequency characte test pattern, as shown in Figure 1.The output voltage that MCU controls two D/A is zero, then two comparers become zero-crossing comparator.Now input, export two sine waves and be all converted into the square wave that dutycycle is 50%, the phase differential between them then can represent with the mistiming of the rising edge of two square waves or negative edge, as shown in Figure 3.If the mistiming of two square wave rising edges is t, sine wave period is T, then phase differential can be expressed as: θ=t/T*2 π.Measure the mistiming of two square wave rising edges, the timer of MCU can be used, allow timer with fixing frequency f
0counting, reads the numerical value c1 of timer Counter when first square wave rising edge arrives, be c2 when the rising edge of second square wave arrives at the numerical value reading counter, then mistiming t=(the c2-c1)/f of two square wave rising edges
0, two sinusoidal wave phase differential can be obtained thus.By control DDS frequency sweep, record the phase differential of each frequency, the phase-frequency characteristic of tested network can be obtained.
The phase differential precision recorded in this approach is mainly subject to the restriction of timer resolution, and the frequency of operation of timer is higher, and resolution is higher, and the mistiming t recorded is more accurate.If the frequency of operation of timer is 72MHz, sine wave freuqency is 1MHz, and phase differential is 90 degree, then the mistiming t error recorded is about 5%, and error is larger.In order to improve measuring accuracy, can adopt in the following method: as Fig. 4, t for some time between the rising edge changing to first square wave at the counting of timer arrives
1, control DDS random delay a period of time starts to export again, makes t during this period of time
1length be random, scope from 0 to Clock cycle of timer, then for same amount of time difference t, due to t
1difference, the difference c2-c1 recorded is also likely different.
Such as, with the Clock cycle T of timer
cLKfor unit, if real time difference t is 5.7 cycles, so according to t
1difference, the mistiming value recorded is 5 or 6 cycles, works as t
1>0.3*T
cLKtime, the mistiming recorded is 6 cycles, works as t
1<0.3*T
cLKtime, the mistiming recorded is 5 cycles.Due to t
1obedience is uniformly distributed, therefore t
1< 0.3*T
cLKthe probability occurred is 0.3, t
1> 0.3*T
cLKthe probability occurred is the probability that 0.7, two values occur is fixing, and namely the probability of 30% records 5 cycles, and the probability of 70% records 6 cycles, therefore, and its mathematical expectation E=5*30%+6*70%=5.7, the just value of real time difference.
According to above principle, before each Measuring Time difference, control DDS random delay a period of time starts to export again, as long as repetitive measurement mistiming t, and the value recorded is averaged, the value of gained just can be made close to actual value.
Those skilled in the art should understand that; the frequency characteristic test method and apparatus of a kind of conversion of device based on the comparison disclosed in this invention can carry out various improvement on the basis not departing from content frame of the present invention; therefore, protection scope of the present invention should be determined by the content of appending claims.
Claims (8)
1. a frequency characteristic test device for device conversion based on the comparison, is characterized in that comprising frequency characteristic measurement module, signal source generation module, MCU control inputs and display module; Described frequency characteristic measurement module is made up of two groups of D/A converters and voltage comparator, be respectively used to the input and output signal measuring tested network, voltage comparator is responsible for surveyed sine wave to be converted into square wave, the numerical information amplitude of sine wave and phase information being converted to square wave sends into MCU process again, D/A converter is controlled by MCU, as an input end of the reference voltage access voltage comparator of voltage comparator; Described signal source generation module is made up of Direct Digital Synthesizer DDS and power amplifier, and DDS is controlled by MCU, and the output of DDS accesses the input end of tested network after the amplification of power amplifier; Described MCU control inputs and display module comprise MCU, external input part and LCD display, user arranges swept frequency range, stepping, model selection by external input part, MCU is according to the output arranging control DDS frequency sweep and D/A, and the output of voltage comparator is processed, result is presented at above LCD display.
2. the frequency characteristic test method utilizing the device based on the comparison of device described in claim to change, is characterized in that:
User arranges swept frequency range, stepping, model selection by outside input; The frequency needing to measure is calculated according to the input MCU of user; According to the difference of model selection, enter amplitude versus frequency characte test pattern or phase-frequency characteristic test pattern; After entering corresponding modes, MCU control DDS frequency sweep exports each frequency needing to measure, and the corresponding amplitude of measurement on each frequency or phase differential; On LCD, frequency characteristic curve diagram is drawn, display measurement result according to test result.
3. the frequency characteristic test method of the conversion of device based on the comparison according to claim 2, it is characterized in that, realize sinusoidal wave peak-value detection method by voltage comparator in conjunction with described D/A converter, measure input, output voltage to obtain the amplitude versus frequency characte of tested network; Adopt improve input, sine wave output signal are converted into square wave by zero-crossing comparator and the method measuring two square wave edge time differences obtains the phase-frequency characteristic of tested network, wherein, the mathematical expectation of mistiming t is made to equal actual value by the randomness of the rising edge to time that control first square wave, repetitive measurement mistiming t is also averaged to make the value of gained mistiming close to its mathematical expectation, i.e. the actual value of time to approach difference.
4. the frequency characteristic test method of the conversion of device based on the comparison according to claim 3, it is characterized in that, described sinusoidal wave peak-value detection method comprises: calibrated by later stage correction detecting the error that needed for edge change, minimum pulse width causes due to MCU; Sweep width by the mode of binary search and improve measuring speed.
5. the frequency characteristic test method of the conversion of device based on the comparison according to claim 4, it is characterized in that, the described error caused the required minimum pulse width of MCU detection edge change is revised by the later stage the concrete calibration steps calibrated and is: according to sine wave period T, the peak value U1 recorded, the minimum pulse width t that MCU can detect, obtaining the sinusoidal wave peak value after calibrating is U=U1/ sin [(1/2-t/T) * π].
6. the frequency characteristic test method of the conversion of device based on the comparison according to claim 4, it is characterized in that, the concrete methods of realizing that the described mode by binary search sweeps width raising measuring speed is: D/A converter is first measured from the intermediate value of span, if it is too low to record value, D/A converter using intermediate value to the interval of maximal value as new span, if it is too high to record value, minimum value to the interval of intermediate value as new span, continues to carry out binary search according to same determination methods by D/A.
7. the frequency characteristic test method of the conversion of device based on the comparison according to claim 6, width is swept specifically by the mode of binary search described in it is characterized in that, D/A converter is first measured from the intermediate value of span, as occurred, negative edge illustrates that value is too low, intermediate value is proceeded binary search to the interval of maximal value as new span by D/A converter, if do not occurred, negative edge illustrates that value is too high, and minimum value is proceeded binary search to the interval of intermediate value as new span by D/A converter.
8. the frequency characteristic test method of the conversion of device based on the comparison according to claim 4, it is characterized in that in the method for measurement two the square wave edge time differences improved, the concrete methods of realizing that the rising edge of described control first square wave makes the mathematical expectation of mistiming t equal actual value to the randomness of time is: control DDS random delay setting-up time starts to export again, rising edge is obeyed time of arrival and is uniformly distributed to make the mathematical expectation of mistiming to equal actual value.
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| CN109586814A (en) * | 2018-12-11 | 2019-04-05 | 国网江西省电力有限公司经济技术研究院 | Power line channel phase-frequency characteristic detection method and detection device |
| CN114008550A (en) * | 2019-05-10 | 2022-02-01 | 西屋电气有限责任公司 | Calibration system and method |
| CN117110732A (en) * | 2023-10-25 | 2023-11-24 | 青岛澳波泰克安全设备有限责任公司 | Electrostatic detection system and electrostatic detection method for phase compensation |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4922343A (en) * | 1988-03-14 | 1990-05-01 | Sony Corporation | Apparatus for detecting frequency of input signal with a digital scanning G-converter |
| CN2246809Y (en) * | 1996-05-16 | 1997-02-05 | 哈尔滨工程大学 | Super low-frequency response tester |
| US6411075B1 (en) * | 1999-03-18 | 2002-06-25 | Nanosurf Ag | Electronic frequency measuring device and its use |
| CN201611380U (en) * | 2010-02-24 | 2010-10-20 | 浙江大学宁波理工学院 | Digital frequency characteristic tester |
| CN101937054A (en) * | 2010-08-30 | 2011-01-05 | 南车株洲电力机车研究所有限公司 | IGCT (Integrated Gate Commutated Thyristor) frequency testing method and device |
| CN203745579U (en) * | 2014-03-21 | 2014-07-30 | 河海大学常州校区 | Frequency characteristic test instrument based on waveform superposition |
| CN203772956U (en) * | 2014-05-21 | 2014-08-13 | 南京信息工程大学 | Quadrature modulation principle-based frequency characteristic tester |
| CN104483619A (en) * | 2014-12-10 | 2015-04-01 | 四川理工学院 | Frequency characteristic testing system based on virtual instrument |
-
2015
- 2015-04-19 CN CN201510184239.3A patent/CN104808056B/en not_active Expired - Fee Related
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4922343A (en) * | 1988-03-14 | 1990-05-01 | Sony Corporation | Apparatus for detecting frequency of input signal with a digital scanning G-converter |
| CN2246809Y (en) * | 1996-05-16 | 1997-02-05 | 哈尔滨工程大学 | Super low-frequency response tester |
| US6411075B1 (en) * | 1999-03-18 | 2002-06-25 | Nanosurf Ag | Electronic frequency measuring device and its use |
| CN201611380U (en) * | 2010-02-24 | 2010-10-20 | 浙江大学宁波理工学院 | Digital frequency characteristic tester |
| CN101937054A (en) * | 2010-08-30 | 2011-01-05 | 南车株洲电力机车研究所有限公司 | IGCT (Integrated Gate Commutated Thyristor) frequency testing method and device |
| CN203745579U (en) * | 2014-03-21 | 2014-07-30 | 河海大学常州校区 | Frequency characteristic test instrument based on waveform superposition |
| CN203772956U (en) * | 2014-05-21 | 2014-08-13 | 南京信息工程大学 | Quadrature modulation principle-based frequency characteristic tester |
| CN104483619A (en) * | 2014-12-10 | 2015-04-01 | 四川理工学院 | Frequency characteristic testing system based on virtual instrument |
Cited By (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106291105B (en) * | 2016-09-12 | 2019-10-01 | 电子科技大学 | A kind of sweep generator based on digital zero intermediate frequency |
| CN106291105A (en) * | 2016-09-12 | 2017-01-04 | 电子科技大学 | A kind of sweep generator based on digital zero intermediate frequency |
| CN106569162A (en) * | 2016-10-17 | 2017-04-19 | 深圳市鼎阳科技有限公司 | Analog bandwidth measurement method and device for logic analyzer probe |
| CN106569162B (en) * | 2016-10-17 | 2019-04-02 | 深圳市鼎阳科技有限公司 | A kind of the analog bandwidth measurement method and device of logic analyser probe |
| CN106680584A (en) * | 2016-11-11 | 2017-05-17 | 中国科学院长春光学精密机械与物理研究所 | All-digital portable spectrum analysis system |
| CN106814308A (en) * | 2017-03-14 | 2017-06-09 | 南宁市高光信息技术有限公司 | A kind of frequency-characteristic measuring-testing instrument |
| CN107132434A (en) * | 2017-04-06 | 2017-09-05 | 西安邮电大学 | A kind of self-operated measuring unit of analog filter Frequency Response |
| CN106950420A (en) * | 2017-05-11 | 2017-07-14 | 国家电网公司 | The zero-acrross ing moment detecting system and its method of power frequency simple alternating current electric signal |
| CN106997004A (en) * | 2017-06-13 | 2017-08-01 | 山东师范大学 | A kind of high-precision intelligent frequency displacement, phase-shift measurement device and method |
| CN107091956A (en) * | 2017-06-19 | 2017-08-25 | 山东交通学院 | A kind of method and circuit for measuring network phase shift parameters |
| CN109586814A (en) * | 2018-12-11 | 2019-04-05 | 国网江西省电力有限公司经济技术研究院 | Power line channel phase-frequency characteristic detection method and detection device |
| CN109586814B (en) * | 2018-12-11 | 2021-04-09 | 国网江西省电力有限公司经济技术研究院 | Power line channel phase-frequency characteristic detection method and detection device |
| CN114008550A (en) * | 2019-05-10 | 2022-02-01 | 西屋电气有限责任公司 | Calibration system and method |
| CN117110732A (en) * | 2023-10-25 | 2023-11-24 | 青岛澳波泰克安全设备有限责任公司 | Electrostatic detection system and electrostatic detection method for phase compensation |
| CN117110732B (en) * | 2023-10-25 | 2024-01-09 | 青岛澳波泰克安全设备有限责任公司 | Electrostatic detection system and electrostatic detection method for phase compensation |
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