CN101470408B - Active measuring method and apparatus employing low frequency clock - Google Patents
Active measuring method and apparatus employing low frequency clock Download PDFInfo
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- CN101470408B CN101470408B CN2007103084649A CN200710308464A CN101470408B CN 101470408 B CN101470408 B CN 101470408B CN 2007103084649 A CN2007103084649 A CN 2007103084649A CN 200710308464 A CN200710308464 A CN 200710308464A CN 101470408 B CN101470408 B CN 101470408B
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Abstract
The invention provides an active measurement method using a low-frequency clock, which includes steps of providing a clock with P MHz frequency as a counting clock for transmitted signals, providing a clock with Q MHz frequency as a counting clock for measured signals, using a (P*10<6>)/(P*1000-1)Hz frequency for continuous measurement for K times, and then obtaining a counting clock with Q*K MHz high frequency, wherein the P, Q and K meet the relation that remainder of Q*(P*1000-1)/P is 1/K. The active measurement method is capable of realizing high-precision counting for time intervals of the transmitted signals and the measured signals during active measurement.
Description
Technical field
The present invention relates to the measurement in the time interval, is a kind of method of utilizing the low frequency clock to realize the active type measure HIAC specifically.
Background technology
Active type measure is meant to passive measurement initiatively launches a signal, receives reflected signal as measured signal.Active type measure is widely used in a lot of applications; Related application fields such as for example active laser range finding, active radar range finding, pulse-echo ultrasonic thickness measurement, pulse-echo ultrasonic inspection; Its basic measuring principle is transmitting of active; Through to the obtaining of measured signal,, accomplish measurements such as time, distance, speed, shapes according to the time interval that transmits with measured signal.
The active laser range finding is through initiatively launching laser signal, surveying position and the distance of object through measuring the laser light reflected signal.Active radar range finding is through active launched microwave signal, measures the microwave signal of reflection and surveys position and the distance of object.The pulse-echo ultrasonic thickness measurement is the instrument that carries out thickness measure according to the ultrasonic pulse principle of reflection; When the probe ultrasonic waves transmitted pulse of audiogage arrives two kinds of different materials interphases through testee; Pulse is reflected back toward probe, and the time of in material, propagating through accurate measurement ultrasound wave is confirmed the thickness of measured material.The pulse-echo ultrasonic inspection is the instrument that carries out defectoscopy according to the ultrasonic pulse principle of reflection; When the probe ultrasonic waves transmitted pulse of reflectoscope arrives inherent vice through testee; Pulse is reflected back toward probe, and the time of in material, propagating through accurate measurement ultrasound wave is confirmed the position of tested defective.
Please with reference to Fig. 1; The active type measure process is with emissioning controling signal pulse and measured signal pulse expression-form; Adopt the high frequency precision clock in the time of measuring, to count, total count value multiply by the clock period and is the time interval that records, and measuring accuracy is the cycle of counting clock.The precision of measuring mainly relies on the frequency that transmits with the counting clock in time interval of measured signal to guarantee; In order to improve the time precision of measurement; The most conspicuous method is exactly to improve the frequency of counting clock, but along with the frequency of counting clock improves, in actual design because the restriction of IC-components; And the technical difficulty brought of high speed circuit and cost improve, and the time precision method that the frequency that improves counting clock purely improves measurement is infeasible.
Realize that at present the method for measuring HIAC has many methods, see U.S. Pat 4982350, US5365238, US4303983 and US6754613.These methods are to using and realize having special application requirements and technological difficulties in the active type measure; The present invention utilizes the method for the low frequency clock realization measurement HIAC that the multichannel phase place is synthetic and difference on the frequency is synthetic; Characteristics in conjunction with the active type measure mode; Utilize two low frequency clocks to have certain corresponding relation, HIAC with the measured signal time interval transmits when realizing active type measure.The technical barrier of its ultimate principle and existence is described through concrete application example in the face of United States Patent (USP) two-way difference on the frequency clock method down.
Please with reference to Fig. 2 a; The method of the synthetic HIAC of the low frequency clock of the two-way high precision phase differential of the U.S.; Utilize 2 difference on the frequencies to be respectively 100MHz and 90MHz combination realization 900MHz HIAC for two low frequency clocks of 10MHz; The 1st pulse signal is for transmitting; The 2nd pulse signal is the pulse-echo signal, and the time of for example in material, propagating through accurate measurement ultrasound wave is confirmed the thickness of measured material, and the 1st pulse transmits and start 90MHz low frequency clock and count; Count value was n1 when the 2nd pulse-echo signal arrived, and started 100MHz low frequency clock simultaneously and counted; Judge through judging 100MHz low frequency clock edge and 90MHz low frequency clock count value; When 100MHz low frequency clock count value is n2; The count value of two clocks is identical; 100MHz low frequency clock edge and 90MHz low frequency clock alignment this moment; Be two parts in the time that the calculating ultrasound wave is propagated in material then, first is number of cycles part t1=n1/ (90 * 106) second that utilizes 90MHz low frequency clock to count, and second portion is to utilize 90MHz low frequency clock and 100MHz low frequency clock to carry out non-integer cycle portions t2=n2 * (1/ (90 * 10 of combinatorial enumeration
6)-1/ (100 * 10
6)) second, then ultrasound wave time of in material, propagating is t=t1+t2=n1/ (90 * 10
6)+n2 * (1/ (90 * 10
6)-1/ (100 * 10
6)) second.
Please with reference to Fig. 2 b; The method of the synthetic HIAC of the low frequency clock of two-way difference on the frequency; Utilize measuring-signal to start 100MHz and 90MHz low frequency clock is counted; Requirement has high-precise synchronization between the low frequency clock of measuring-signal and two-way difference on the frequency, because the low frequency Clock enable of two-way difference on the frequency all relies on time measurement signal to start, counts with first pulse signal starting 90MHz low frequency clock; It is ty1 that pulse signal starting 90MHz low frequency clock need pass through delay time, and the delay time error is Δ ty1; Count with second pulse signal starting 100MHz low frequency clock, it is ty2 that pulse signal starting 100MHz low frequency clock need pass through delay time, and the delay time error is Δ ty2; Then first is the number of cycles part t1+ty1+ Δ ty1=n1/ (90 * 106) that utilizes 90MHz low frequency clock to count+ty1+ Δ ty1 second, and second portion is to utilize 90MHz low frequency clock and 100MHz low frequency clock to carry out non-integer cycle portions t2-(ty2+ Δ ty2)=n2 * (1/ (90 * 10 of combinatorial enumeration
6)-1/ (100 * 10
6))-(ty2+ Δ ty2) second, then ultrasound wave time of in material, propagating is t=t1+ty1+ Δ ty1+t2-(ty2+ Δ ty2) second.Owing to adopt measuring-signal to start clock signal, adopt clock crystal still be clock chip all be to be difficult to realize with the delay time error control in nanosecond.
Summary of the invention
The object of the present invention is to provide a kind of active measuring method that utilizes low-frequency clock, HIAC with the measured signal time interval transmits in the time of can realizing active type measure.
Another object of the present invention is to provide a kind of measurement mechanism that adopts above-mentioned active measuring method; Adopt processor and programming device or counter cheaply; Utilize processor and programming device or counter low frequency clock to have certain corresponding relation, HIAC with the measured signal time interval transmits when realizing active type measure.
On the one hand, the method for utilizing the active type measure of low-frequency clock of the present invention comprises:
It is that the clock of P megahertz is as the counting clock that transmits that one frequency is provided;
It is the counting clock of the clock of Q megahertz as measured signal that one frequency is provided;
With (P * 10
6)/(P * 1000-1) hertz frequency is now carried out K measurement continuously;
Wherein, described P, Q and K satisfy relation, and Q * (remainder of P * 1000-1)/P is 1/K.
Obtain Q * K megahertz high-frequency count clock.
On the other hand, the active type measure device that utilizes low-frequency clock of the present invention comprises:
Counting circuit, said counting circuit comprises programming device;
Processing unit, said processing unit control is launched ultrasound wave K time with the M hertz, with the clock count of P megahertz to transmitting;
Said programming device is with the clock count of Q megahertz to reflected signal;
Wherein said P, Q, M and K satisfy relation, and Q * (remainder of P * M-1)/P is 1/K.
This measurement mechanism also comprises fuselage, display screen, keyboard, probe, receiver socket, emission socket and amplification integeral type circuit; Wherein the keyboard input instruction is given processing unit; Extremely popped one's head in through emission socket output electric pulse by processing unit control radiating circuit, the excitation piezo chips produces pulse ultrasonic wave, and ultrasound wave forms repeatedly reflection between the testee upper and lower surface; Reflection wave is received by probe and is transformed into electric signal through piezo chips; After amplification integeral type circuit amplifies integer, be sent to counting circuit through receiver socket, read and be sent to processing unit after the measurement data in the counting circuit and handle, and export end product to display screen.
This measurement mechanism is any in active laser stadimeter, active radar range finder or the pulse-echo reflectoscope.
This measurement mechanism is an audiogage.
The present invention utilizes two low frequency clocks; The counting clock that transmits during as active type measure and the counting clock of measured signal; Utilize two low frequency clocks to have certain corresponding relation, HIAC with the measured signal time interval transmits when realizing active type measure.
The present invention utilizes the low frequency clock to replace the high-frequency clock; Solved the series of technical of bringing in design of high-frequency clock and the realization; This patent of invention is for the method for the synthetic HIAC of low frequency clock of the two-way difference on the frequency of the U.S.; Solve the difficult point that the high-precise synchronization time realizes between the low frequency clock of measuring-signal and two-way difference on the frequency, solved the difficulty that low frequency clock high precision phase differential produces, and the harshness of low frequency clock high-precise synchronization time requirement.
The present invention utilizes two low frequency clocks; The counting clock that transmits during as active type measure and the counting clock of measured signal; The basic expression-form of active type measure is with emissioning controling signal pulse and measured signal pulse; Adopt low-frequency clock in the time of measuring, repeatedly to count and utilize two low frequency clocks to have certain corresponding relation, HIAC with the measured signal time interval transmits when realizing active type measure.
Description of drawings
Accompanying drawing described herein is used to provide further understanding of the present invention, constitutes the application's a part, does not constitute qualification of the present invention.In the accompanying drawings:
Fig. 1 is the principle schematic of active type measure;
Fig. 2 a is that the low frequency clock of two-way high precision difference on the frequency synthesizes the clock synoptic diagram of the method for HIAC;
Fig. 2 b is the clock synoptic diagram that the method for the synthetic HIAC of low frequency clock of two-way high precision difference on the frequency exists time-delay and synchronous error;
Fig. 3 is the clock synoptic diagram according to active type measure principle of the present invention;
Fig. 4 is the clock synoptic diagram according to the active type measure of the embodiment of the invention;
Fig. 5 is the structural representation of audiogage according to another embodiment of the present invention;
Fig. 6 is the circuit theory diagrams of audiogage according to another embodiment of the present invention.
Embodiment
For making the object of the invention, technical scheme and advantage clearer,, the present invention is explained further details below in conjunction with embodiment and accompanying drawing.At this, exemplary embodiment of the present invention and explanation thereof are used to explain the present invention, but not as to qualification of the present invention.
The embodiment of the invention provides a kind of and utilizes the active measuring method of low-frequency clock and adopt the audiogage that changes method.Below in conjunction with accompanying drawing the present invention is elaborated.
As shown in Figure 3, the counting clock that the active measuring method that utilizes low-frequency clock of the present invention transmits when utilizing low frequency clock that two frequencies are respectively P megahertz and Q megahertz as active type measure and the counting clock of measured signal are with (P * 10
6)/(P * 1000-1) frequency of hertz is carried out K measurement continuously; When the counting clock P megahertz that transmits, measured signal technology clock Q megahertz; With measure number of times and concern Q * (when the remainder of P * 1000-1)/P is 1/K below satisfying; Transmit in the time of can realizing active type measure HIAC with the measured signal time interval can reach the K measuring accuracy doubly of Q megahertz.
Embodiment 1
The clock synoptic diagram of the active type measure that utilizes low-frequency clock that following reference is shown in Figure 4 specifies the active measuring method that utilizes low-frequency clock of the present invention.The present invention adopts the processor of clock frequency 4MHz, carries out the 39.84MHz count frequency in conjunction with programming device cheaply, thereby realizes that count frequency is the accurate counting to Measuring Time of 1G.Programming device is to utilize the hardware logic programming to realize the certain logic and the device of sequential relationship.In the 1st measuring process; Through processor low frequency clock control transponder pulse signal; Start programming device simultaneously or counter low frequency clock paired pulses reflected signal is counted, the time of in material, propagating through accurate measurement ultrasound wave is confirmed the thickness of measured material; After the 1st time through 3999 all after dates of processor low frequency clock; Through the 2nd transponder pulse signal of processor low frequency clock control; Start programming device simultaneously or counter low frequency clock paired pulses reflected signal is counted; And this moment programming device or 39830.04 cycles of counter low frequency clock, both programming device or counter low frequency clock had existed the phase differential in 0.04 cycle when measuring for the first time; In like manner in the 3rd measuring process; Programming device or counter low frequency clock exist the phase differential in 0.08 cycle when measuring with the first time; In the 26th measuring process, programming device or the counter low frequency clock phase place when measuring for the first time is identical.Suppose that 25 infra-low frequency rate clocks are respectively n1 to the counting of the time of propagation, n2 ..., n25 is n=n1+n2+ with 996MHz HIAC value then ... + n25, then calculating the time that ultrasound wave propagates in material is the t=n/996 microsecond.Owing under the good situation of couple state, measure to carry out 25 times continuously near the frequency of 1KHz, and satisfy the ultrasonic thickness measurement requirement fully, accomplish precision and measure for the 0.002988mm ultrasonic thickness measurement for its circular error measuring error of active crystal oscillator.
Embodiment 2
This patent of invention combine the pulse-echo audiogage should be used for specify; The pulse-echo audiogage is the instrument that carries out thickness measure according to the ultrasonic pulse principle of reflection; When the probe ultrasonic waves transmitted pulse of audiogage arrives two kinds of different materials interphases through testee; Pulse is reflected back toward probe, and the time of in material, propagating through accurate measurement ultrasound wave is confirmed the thickness of measured material.
With reference to audiogage shown in Figure 5, this audiogage includes fuselage 41, display screen 42, keyboard 43, probe 44, receiver socket 45, emission socket 46.Its ultimate principle probe 44 emission ultrasonic pulses of serving as reasons arrive testees and in object, propagate; Be reflected back toward probe when arriving material interface; Through the thickness of definite measured material of the accurate travel-time of measurement ultrasound wave in material, this audiogage has adopted the active measuring method of low-frequency clock that utilizes of the present invention to measure the time that ultrasound wave transmits in material.By keyboard 43 input instructions, transmit to visiting first through emission socket 46, feed back to processing unit by probe emission ultrasonic pulse and with the ultrasonic pulse reflected signal through receiver socket 45, signal is shown by display screen 42 through the data that processing obtains.
Circuit theory synoptic diagram with reference to audiogage shown in Figure 6; Give processing unit 51 by keyboard 53 input instructions, to probe, the excitation piezo chips produces pulse ultrasonic wave by processing unit control radiating circuit 54 output electric pulses; Ultrasound wave forms repeatedly reflection between the testee upper and lower surface; Reflection wave is transformed into electric signal through piezo chips, after amplification integeral type circuit 56 amplifies integer, is sent to counting circuit 57; Read and be sent to processing unit 51 after the measurement data in the counting circuit 57 and handle, and export end product to display screen 52.The programming device that wherein comprises the counting clock that utilizes the active measuring method control reflection wave that utilizes low-frequency clock of the present invention in the counting circuit 57, processing unit 51 utilize clock and the survey frequency of utilizing the active measuring method control ultrasonic emitting of low-frequency clock of the present invention.
Above-described embodiment; The object of the invention, technical scheme and beneficial effect have been carried out further explain, and institute it should be understood that the above is merely embodiment of the present invention; And be not used in qualification protection scope of the present invention; All within spirit of the present invention and principle, any modification of being made, be equal to replacement, improvement etc., all should be included within protection scope of the present invention.
Claims (6)
1. a method of utilizing the active type measure of low-frequency clock is characterized in that, this method comprises:
It is that the clock of P megahertz is as the counting clock that transmits that one frequency is provided;
It is the counting clock of the clock of Q megahertz as measured signal that one frequency is provided;
With (P * 10
6)/(P * 1000-1) frequency of hertz is carried out K measurement continuously;
Wherein, described P, Q and K satisfy relation, and Q * (remainder of P * 1000-1)/P is 1/K.
2. measuring method according to claim 1 is characterized in that: described P megahertz and Q mhz frequencies clock are the low frequency clock that frequency is lower than 100 megahertzes.
3. active type measure device that utilizes low-frequency clock is characterized in that this measurement mechanism comprises:
Counting circuit, said counting circuit comprises programming device;
Processing unit, said processing unit control is with (P * 10
6)/(P * 1000-1) hertz is launched ultrasound wave K time, with the clock count of P megahertz to transmitting, obtains Q * K megahertz high-frequency count clock;
Said programming device is with the clock count of Q megahertz to reflected signal;
Wherein said P, Q and K satisfy relation, and Q * (remainder of P * 1000-1)/P is 1/K.
4. measurement mechanism according to claim 3; It is characterized in that: this measurement mechanism also comprises fuselage, display screen, keyboard, probe, receiver socket, emission socket and amplification integeral type circuit; Wherein the keyboard input instruction is given processing unit; Extremely pop one's head in excitation piezo chips emission active probe signal, the reflection of active probe signal testee through emission socket output electric pulse by processing unit control radiating circuit; Reflected probe signal is received by probe and is transformed into electric signal through piezo chips; After amplification integeral type circuit amplifies integer, be sent to counting circuit through receiver socket, read and be sent to processing unit after the measurement data in the counting circuit and handle, and export end product to display screen.
5. according to claim 3 or 4 described measurement mechanisms, it is characterized in that: this measurement mechanism is any in active laser stadimeter, active radar range finder or the pulse-echo reflectoscope.
6. according to claim 3 or 4 described measurement mechanisms, it is characterized in that: this measurement mechanism is an audiogage.
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|---|---|---|---|
| CN2007103084649A CN101470408B (en) | 2007-12-29 | 2007-12-29 | Active measuring method and apparatus employing low frequency clock |
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| CN2007103084649A CN101470408B (en) | 2007-12-29 | 2007-12-29 | Active measuring method and apparatus employing low frequency clock |
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| CN101470408B true CN101470408B (en) | 2012-01-11 |
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Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102073268B (en) * | 2009-11-24 | 2012-07-04 | 华东光电集成器件研究所 | High-precision pulse time interval measurement circuit |
| CN103175587B (en) * | 2013-03-01 | 2015-02-18 | 电子科技大学 | Guided wave radar liquid indicator |
| CN103488074B (en) * | 2013-09-13 | 2016-02-10 | 电子科技大学 | A kind of amplitude variation signal transit time measurement device |
| CN103913211B (en) * | 2014-04-14 | 2017-02-15 | 姜跃炜 | Time coefficient calibration method of ultrasonic water meter |
| CN104614028B (en) * | 2015-03-07 | 2019-02-12 | 姜跃炜 | Split-second precision calibration method for ultrasonic flowmeter |
| US9577684B1 (en) * | 2015-11-25 | 2017-02-21 | Intel IP Corporation | High frequency time interleaved digital to time converter (DTC) |
| CN105651213B (en) * | 2016-03-30 | 2018-08-14 | 上海云统信息科技有限公司 | Toothed plate of jaw crusher abrasion detection sensor and detection method |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1940777A (en) * | 2005-06-22 | 2007-04-04 | 阿米特克公司 | High resolution time interval measurement apparatus and method |
| US7379395B2 (en) * | 2004-06-30 | 2008-05-27 | Teradyne, Inc. | Precise time measurement apparatus and method |
| CN101194183A (en) * | 2005-06-10 | 2008-06-04 | 株式会社拓普康 | Time difference measuring apparatus, distance measuring apparatus, and distance measuring method |
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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7379395B2 (en) * | 2004-06-30 | 2008-05-27 | Teradyne, Inc. | Precise time measurement apparatus and method |
| CN101194183A (en) * | 2005-06-10 | 2008-06-04 | 株式会社拓普康 | Time difference measuring apparatus, distance measuring apparatus, and distance measuring method |
| CN1940777A (en) * | 2005-06-22 | 2007-04-04 | 阿米特克公司 | High resolution time interval measurement apparatus and method |
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Effective date of registration: 20151013 Address after: 100085, 28 West Road, Beijing, Haidian District, building 2313, room 3, 2 Patentee after: Beijing times peak Technology Co., Ltd. Address before: 100085, 28 West Road, Beijing, Haidian District, 1, two floor Patentee before: Beijing TIME High-technology Ltd. |
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Granted publication date: 20120111 Termination date: 20181229 |
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