CN102305827A - Love wave sensor testing system based on frequency sweeping technology, and a testing method thereof - Google Patents
Love wave sensor testing system based on frequency sweeping technology, and a testing method thereof Download PDFInfo
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- CN102305827A CN102305827A CN201110247482A CN201110247482A CN102305827A CN 102305827 A CN102305827 A CN 102305827A CN 201110247482 A CN201110247482 A CN 201110247482A CN 201110247482 A CN201110247482 A CN 201110247482A CN 102305827 A CN102305827 A CN 102305827A
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Abstract
The invention relates to a love wave sensor testing system based on a frequency sweeping technology, and a testing method thereof. The invention belongs to the field of novel sensors. The system structure provided by the invention comprises a signal source module, a love wave sensor, a signal converting module, a signal collecting module, a microcontroller module, and a displaying module. The testing method is based on the correspondence between the resonance frequency offset of the love wave sensor and an object requiring testing. Within a certain frequency range, frequency sweeping is carried out by the signal source with certain frequency intervals, and pumping signals are output. An amplitude ratio between sensor input pumping signals and output responding signals of each frequency point within the frequency sweeping range is tested, such that an amplitude-frequency curve of the love wave sensor is obtained, resonance frequency and offset are obtained, and characteristic parameters of the object requiring testing are determined. With the system and the method provided by the invention, a frequency sweeping function of a network analyzer is realized, the application of the love wave sensor is no longer restricted in a laboratory, and industrial on-line application of the love wave sensor is realized.
Description
Technical field
The present invention relates to a kind of love wave sensor, relate in particular to a kind of love wave sensor test macro and method of testing thereof, belong to the novel sensor field based on sweep frequency technique.
Background technology
Resonance is a specific character of system, and on resonant frequency point, system keeps intake with minimum loss, and system responses is significantly strengthened.Resonant transducer is modulated the resonance characteristic parameter of resonator based on tested physics, chemical parameters, changes the detection that realizes measurand through the resonant parameter of measuring resonator.
Sonic sensor is a kind of novel resonant transducer.Sonic sensor as Sensitive Apparatus, utilizes piezoelectric effect with piezoelectric, on piezoelectric substrate, inspires elastic wave through transducer, mainly changes with measurand according to the resonance frequency of sound wave and realizes measuring ability.As a rule, sonic sensor can be divided into three types of surface acoustic wave sensors, Lamb wave sensor, love wave sensor.Wherein, love wave sensor is suitable for Liquid Detection most, also is fit to gas detection simultaneously.
Up to now, the degree of being practical of love wave sensor also is not very high, and most research still is in laboratory stage, and main surveying instrument is a network analyzer.If the sensor testing system of designing can be realized the frequency sweep function of network analyzer, can make love wave sensor break through the laboratory and use limitation, realize industrial online application.
Summary of the invention
Technical matters to be solved by this invention provides a kind of love wave sensor test macro and method of testing thereof based on sweep frequency technique, realizes the frequency sweep function of network analyzer, makes love wave sensor break through the laboratory and uses limitation, realizes industrial online application.
The present invention adopts following technical scheme for solving the problems of the technologies described above:
A kind of love wave sensor test macro based on sweep frequency technique comprises signal source module, love wave sensor, signal conversion module, signal acquisition module, micro controller module, display module; Wherein: the output terminal of signal source module connects the input end of love wave sensor and the first input end of signal conversion module respectively; The output terminal of love wave sensor connects second input end of signal conversion module; The output terminal of signal conversion module connects the input end of signal acquisition module; The output terminal of signal acquisition module connects the input end of micro controller module, and the output terminal of micro controller module connects the input end of signal source module and the input end of display module.
Further; Love wave sensor test macro based on sweep frequency technique of the present invention; Said love wave sensor comprises piezoelectric substrate, input interdigital transducer, output interdigital transducer, non-piezoelectric membrane; Wherein import interdigital transducer and output interdigital transducer and be deposited on the piezoelectric substrate surface, divide left and right sides symmetry arrangement, non-piezoelectric membrane sputter or be spin-coated on the piezoelectric substrate surface and cover input interdigital transducer and output interdigital transducer.
Further, the love wave sensor test macro based on sweep frequency technique of the present invention, said signal source module adopts the AD9912 chip of U.S. ADI company.
Further, the love wave sensor test macro based on sweep frequency technique of the present invention, said signal conversion module adopts the AD8302 chip of U.S. ADI company.
Further, the love wave sensor test macro based on sweep frequency technique of the present invention, said signal acquisition module adopts the integrated A/D change-over circuit of microprocessor internal to realize.
Further, the love wave sensor test macro based on sweep frequency technique of the present invention, said micro controller module adopts the STM32 based on the ARM kernel.
The present invention also provides a kind of method of testing of the love wave sensor test macro based on sweep frequency technique, comprises the steps:
Steps A when love wave sensor is in reference state, i.e. during not load measurand, adopts micro controller module control signal source with certain frequency interval frequency sweep output drive signal; Wherein, swept frequency range is the center with the theoretical resonance frequency of love wave sensor, and the bound of said frequency is confirmed with the parameter and the measurand of love wave sensor;
Step B transfers to output response signal behind the love wave sensor with the described pumping signal of steps A;
Step C converts the amplitude ratio of the said pumping signal of steps A and the said response signal of step B into analog voltage signal, converting analog voltage signal into digital signal through the A/D conversion then, sends into micro controller module again;
Step D; Repeating step B is to step C; The digital signal of the love wave sensor input signal of all Frequency points and the amplitude ratio of output response signal in obtaining about swept frequency range; Adopt micro controller module that said digital signal is handled then, obtain the amplitude-versus-frequency curve of love wave sensor, and the resonance frequency when obtaining love wave sensor and being in reference state;
Step e, when love wave sensor is in the measurement state, i.e. during load measurand, repeating step A is to step D, the resonance frequency when obtaining love wave sensor and being in the measurement state, and the resonance frequency during with reference state is compared and is obtained the skew of resonance frequency;
Step F, the resonance frequency shift that obtains through step e obtains the individual features parameter of measurand, and the characteristic parameter that demonstrates measurand through display module is to offer the user.
The present invention adopts above technical scheme compared with prior art, has following technique effect:
1. compare with the Lamb wave sensor with surface acoustic wave sensor, love wave sensor is suitable for Liquid Detection most, also is fit to gas detection simultaneously.
2. the present invention can realize the frequency sweep function of network analyzer, uses limitation thereby make love wave sensor break through the laboratory, realizes industrial online application.
Description of drawings
Fig. 1 is a construction module block diagram of the present invention.
Fig. 2 is a love wave sensor structural representation of the present invention.
Fig. 3 is a test circuit module block diagram of the present invention.
Label title among the above-mentioned figure: the 1-piezoelectric substrate, 2-imports interdigital transducer, 3-output interdigital transducer, the non-piezoelectric membrane of 4-.
Embodiment
Below in conjunction with accompanying drawing technical scheme of the present invention is done further detailed description:
As shown in Figure 1, a kind of love wave sensor test macro based on sweep frequency technique.Its structure comprises signal source module, love wave sensor, signal conversion module, signal acquisition module, micro controller module, display module.Wherein: the output terminal of signal source module connects the input end of sensor assembly and the first input end of signal conversion module; The output terminal of sensor assembly connects second input end of signal conversion module; The output terminal of signal conversion module connects the input end of signal acquisition module; The output terminal of signal acquisition module connects the input end of micro controller module, and the output terminal of micro controller module connects the input end of signal source module and the input end of display module.
The manufacture craft of love wave sensor is divided into substrate making, interdigital graphic making, interdigital duplicating and four parts of film spin coating, and the back that completes encapsulates it.Love wave sensor is in kind also littler than one circle coin, belongs to the microsensor category, is suitable for micro liquid and gas detection.
As shown in Figure 2, the love wave sensor structural representation.Comprise piezoelectric substrate 1, input interdigital transducer 2, output interdigital transducer 3, non-piezoelectric membrane 4.Wherein piezoelectric substrate 1 material therefor is 36 ° of YX lithium tantalates; Input interdigital transducer 2 is deposited on the piezoelectric substrate surface with output interdigital transducer 3, and material therefor is a copper, and interdigital logarithm is 75 pairs; The interdigital cycle is 11.06 μ m; Interdigital width is 2.875 μ m, and interdigital spacing is 2.875 μ m, and interdigital thickness is 0.2 μ m; The aperture is 1750 μ m, and two centre distance between interdigital are 6160 μ m; Non-piezoelectric membrane 4 is spin-coated on piezoelectric substrate 1 surface and covers input interdigital transducer and output interdigital transducer, and material therefor is the SU-8 photoresist, and thickness is 0.28 μ m.x
1Direction is the direction of propagation, Love wave, x
2Direction is the horizontal shear direction, x
3Direction is the substrate normal direction.
As shown in Figure 3, a kind of love wave sensor test circuit module block diagram based on sweep frequency technique.Signal source module is realized through DDS (Direct Digital Synthesizer, Direct Digital compositor) circuit, adopts the AD9912 chip of U.S. ADI company, and this chip can produce the sine wave signal up to 400MHZ, and response speed is fast, and frequency resolution is high; Signal conversion module converts sensor input signal and output response signal amplitude ratio into analog voltage signal, adopts the AD8302 chip of U.S. ADI company; Signal acquisition module adopts the integrated A/D change-over circuit of microprocessor internal to realize; Micro controller module adopts the STM32 based on the ARM kernel.
Love wave sensor method of testing based on sweep frequency technique comprises the steps:
1) is in reference state when love wave sensor; During i.e. not load measurand; The DDS circuit under the control of STM32 with certain frequency frequency sweep output drive signal at interval; Swept frequency range is the center with the theoretical resonance frequency of Love wave device, frequency limits view sensor parameter and measurand and decide;
2) output of DDS circuit divides two-way, and one the tunnel is used for excitation input interdigital transducer, and the input channel B of AD8302 circuit is inserted on another road;
3) love wave sensor is under the effect of input interdigital transducer input signal, and the output interdigital transducer output response signal inserts the input channel A of AD8302 circuit;
4) the AD8302 circuit converts the amplitude of input channel A and B ratio into analog voltage signal, sends into the A/D change-over circuit through output terminal;
5) the A/D change-over circuit converts analog voltage signal into digital signal, sends into STM32;
6) in the one whole frequency sweep, STM32 handles the digital signal that the A/D change-over circuit is sent here, the resonance frequency when obtaining the amplitude-versus-frequency curve of love wave sensor and obtaining reference state;
7) be in the measurement state when love wave sensor, i.e. during load measurand, repeating step 1 is to step 6, the resonance frequency when obtaining love wave sensor and being in the measurement state, and the resonance frequency during with reference state is compared and is obtained the skew of resonance frequency;
8) characteristic parameter of this resonance frequency shift and measurand has corresponding relation, and the characteristic parameter that demonstrates measurand through display module is to offer the user.
Claims (7)
1. the love wave sensor test macro based on sweep frequency technique is characterized in that: comprise signal source module, love wave sensor, signal conversion module, signal acquisition module, micro controller module, display module; Wherein: the output terminal of signal source module connects the input end of love wave sensor and the first input end of signal conversion module respectively; The output terminal of love wave sensor connects second input end of signal conversion module; The output terminal of signal conversion module connects the input end of signal acquisition module; The output terminal of signal acquisition module connects the input end of micro controller module, and the output terminal of micro controller module connects the input end of signal source module and the input end of display module.
2. the love wave sensor test macro based on sweep frequency technique according to claim 1; It is characterized in that: said love wave sensor comprises piezoelectric substrate, input interdigital transducer, output interdigital transducer, non-piezoelectric membrane; Wherein importing interdigital transducer and output interdigital transducer is deposited on the piezoelectric substrate surface; Divide left and right sides symmetry arrangement, non-piezoelectric membrane sputter or be spin-coated on the piezoelectric substrate surface and cover input interdigital transducer and output interdigital transducer.
3. the love wave sensor test macro based on sweep frequency technique according to claim 1 is characterized in that: said signal source module adopts the AD9912 chip of U.S. ADI company.
4. the love wave sensor test macro based on sweep frequency technique according to claim 1 is characterized in that: said signal conversion module adopts the AD8302 chip of U.S. ADI company.
5. the love wave sensor test macro based on sweep frequency technique according to claim 1 is characterized in that: said signal acquisition module adopts the integrated A/D change-over circuit of microprocessor internal to realize.
6. the love wave sensor test macro based on sweep frequency technique according to claim 1 is characterized in that: said micro controller module adopts the STM32 based on the ARM kernel.
7. the method for testing of the love wave sensor test macro based on sweep frequency technique as claimed in claim 1 is characterized in that comprising the steps:
Steps A when love wave sensor is in reference state, i.e. during not load measurand, adopts micro controller module control signal source with certain frequency interval frequency sweep output drive signal; Wherein, swept frequency range is the center with the theoretical resonance frequency of love wave sensor, and the bound of said frequency is confirmed with the parameter and the measurand of love wave sensor;
Step B transfers to output response signal behind the love wave sensor with the described pumping signal of steps A;
Step C converts the amplitude ratio of the said pumping signal of steps A and the said response signal of step B into analog voltage signal, converting analog voltage signal into digital signal through the A/D conversion then, sends into micro controller module again;
Step D; Repeating step B is to step C; The digital signal of the love wave sensor input signal of all Frequency points and the amplitude ratio of output response signal in obtaining about swept frequency range; Adopt micro controller module that said digital signal is handled then, obtain the amplitude-versus-frequency curve of love wave sensor, and the resonance frequency when obtaining love wave sensor and being in reference state;
Step e, when love wave sensor is in the measurement state, i.e. during load measurand, repeating step A is to step D, the resonance frequency when obtaining love wave sensor and being in the measurement state, and the resonance frequency during with reference state is compared and is obtained the skew of resonance frequency;
Step F, the resonance frequency shift that obtains through step e obtains the characteristic parameter of measurand, and the characteristic parameter that demonstrates measurand through display module is to offer the user.
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| CN103278181A (en) * | 2013-05-03 | 2013-09-04 | 东南大学 | Wireless reading circuit for passive LC resonator sensor |
| CN103292836A (en) * | 2013-05-15 | 2013-09-11 | 中北大学 | Measuring system and method of LC (inductive capacitive) sensor in sweep frequency mode |
| CN103438911A (en) * | 2013-07-25 | 2013-12-11 | 中北大学 | LC resonance sensor reading system and method under fixed frequency mode |
| CN103575315A (en) * | 2013-11-05 | 2014-02-12 | 南京航空航天大学 | Method using delay line type surface acoustic wave sensor to test characteristic parameters of article |
| CN103727964A (en) * | 2013-11-22 | 2014-04-16 | 中北大学 | Mechanical parameter measuring system and method based on LC resonance sensor |
| CN104391204A (en) * | 2014-12-04 | 2015-03-04 | 南车株洲电机有限公司 | Detection method and device for resonant frequency of locomotive transformer |
| CN107741455A (en) * | 2017-11-27 | 2018-02-27 | 桂林电子科技大学 | A kind of gas-detecting device based on dot matrix piezoelectric film sensor |
| CN108132095A (en) * | 2017-12-21 | 2018-06-08 | 苏州斯威高科信息技术有限公司 | A kind of measuring method and device of structural member self-resonant frequency |
| CN108205000A (en) * | 2018-03-06 | 2018-06-26 | 量准（上海）医疗器械有限公司 | Ovulation detecting device |
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Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN103278181A (en) * | 2013-05-03 | 2013-09-04 | 东南大学 | Wireless reading circuit for passive LC resonator sensor |
| CN103278181B (en) * | 2013-05-03 | 2016-03-16 | 东南大学 | A kind of wireless sensing circuit of passive LC resonator sensor |
| CN103292836A (en) * | 2013-05-15 | 2013-09-11 | 中北大学 | Measuring system and method of LC (inductive capacitive) sensor in sweep frequency mode |
| CN103438911A (en) * | 2013-07-25 | 2013-12-11 | 中北大学 | LC resonance sensor reading system and method under fixed frequency mode |
| CN103575315A (en) * | 2013-11-05 | 2014-02-12 | 南京航空航天大学 | Method using delay line type surface acoustic wave sensor to test characteristic parameters of article |
| CN103727964A (en) * | 2013-11-22 | 2014-04-16 | 中北大学 | Mechanical parameter measuring system and method based on LC resonance sensor |
| CN103727964B (en) * | 2013-11-22 | 2016-11-16 | 中北大学 | A kind of mechanics parameter based on LC resonant transducer measures system and measuring method |
| CN104391204A (en) * | 2014-12-04 | 2015-03-04 | 南车株洲电机有限公司 | Detection method and device for resonant frequency of locomotive transformer |
| CN107741455A (en) * | 2017-11-27 | 2018-02-27 | 桂林电子科技大学 | A kind of gas-detecting device based on dot matrix piezoelectric film sensor |
| CN108132095A (en) * | 2017-12-21 | 2018-06-08 | 苏州斯威高科信息技术有限公司 | A kind of measuring method and device of structural member self-resonant frequency |
| CN108205000A (en) * | 2018-03-06 | 2018-06-26 | 量准（上海）医疗器械有限公司 | Ovulation detecting device |
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