CN100501421C - Fast frequency measuring system and method - Google Patents
Fast frequency measuring system and method Download PDFInfo
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- CN100501421C CN100501421C CNB2005101034858A CN200510103485A CN100501421C CN 100501421 C CN100501421 C CN 100501421C CN B2005101034858 A CNB2005101034858 A CN B2005101034858A CN 200510103485 A CN200510103485 A CN 200510103485A CN 100501421 C CN100501421 C CN 100501421C
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Abstract
The present invention relates to a quick frequency measurement system and its method, belonging to the field of communication technology. Said system includes frequency regulator, frequency measurer and control processor. Said invention utilizes the frequency regulator to regulate tested signal and reference signal, prolong testing time length of tested signal, raise frequency of reference signal so as to obtain high-frequency count pulse, then the frequency measurer can utilize the above-mentioned high-frequency count pulse to measure regulated tested signal.
Description
Technical field
The present invention relates to communication technical field, relate in particular to a kind of fast frequency measuring system and method.
Background technology
At present, the research of frequency measuring method more and more comes into one's own in TT﹠C system, because the frequency signal strong interference immunity, be easy to transmit, can reach higher measuring accuracy, therefore, the transducing signal of multiple non-frequency quantity all will be converted into frequency quantity and measure, and frequency measuring method commonly used has: synchronous frequency measurement method of direct frequency measurement method and multicycle.
Described direct frequency measurement method is the simplest frequency measuring method, inserts pulse exactly in given signal strobe, by the counter circuit of necessity, obtains the number of filler pulse, thereby calculates the frequency or the cycle of measured signal.
In measuring process, the size of basis signal frequency, measuring method are divided into two kinds:
When (1) measured signal frequency was higher: usually the selection standard frequency signal was as signal strobe, and with measured signal as filler pulse, establishing the measured signal count value is N, standard-frequency signal is f
0, its cycle is T
0, then the frequency measurement of this method of testing is f
x=N/T
0, since exist to the measured signal counting ± 1 word error, so the accuracy of measuring is Δ f
x=± 1/T
0
When (2) measured signal frequency is low: select for use measured signal as signal strobe usually, and with standard-frequency signal as filler pulse, the count value of the accurate frequency signal of bidding is N, frequency is f
0, the cycle is T
0, then the frequency measurement of this measuring method is fx=1/ (N*T
0), since exist standard-frequency signal counting ± 1 word error, so the accuracy of measuring is Δ f=± f
x 2/ f
0
The major defect of this direct frequency measurement method is: because the existence of ± 1 word error, be difficult to take into account the measurement that low frequency and high frequency are realized reciprocity accuracy, so measuring accuracy is lower.
Synchronous frequency measuring method of described multicycle is a kind of frequency measuring method that develops on the basis of direct frequency measurement method, in present frequency measurement system, be widely used, be not the value of fixing the gate time of synchronous frequency measurement counting multicycle, but the integral multiple in measured signal cycle, promptly synchronous with measured signal, therefore eliminated to the measured signal counting produce ± 1 word error, accuracy improves greatly, and reached whole measurement frequency range etc. accuracy measurement, the measuring principle waveform as shown in Figure 1, this multi-period synchronizing method frequency measurement principle is as described below:
At first, provide the gate opening signal by operation circuit, at this moment, counter does not begin counting, but the rising edge of measured signal by the time is when arriving, just really begin counting, then, two set of counters respectively to measured signal and the time main pulse counting, after operation circuit provides the closing gate signal, counter does not stop counting immediately, but by the time measured signal negative edge moment of coming just really finish counting, finish the one-shot measurement process.As can be seen, actual gate does not equate with the gate of setting is strict, but maximum difference is no more than the one-period of measured signal, and Measurement Resolution is:
Δf
x＝±1/(τ×f
0)，
Annotate: τ is actual gate time
As can be seen from the above equation, the size of Measurement Resolution and measured signal frequency is irrelevant, and is only relevant with gate and timebase frequency, promptly realized the accuracy measurement that waits in the tested frequency band.Gate time is long more, and timebase frequency is high more, and resolution is high more.
Under quick Testing requirement, in order to reach higher accuracy of measurement, need shorten gate time, so must adopt higher timebase frequency, so just may increase cost, simultaneously, the time main pulse frequency can not unconfinedly improve, so synchronous frequency measurement method of described multicycle can not be taken into account fast, the frequency measurement requirement of pin-point accuracy.
For this reason, high speed, high-precision frequency measurement requirement are satisfied in the measurement that need provide a kind of method can realize high-precision frequency accuracy.
Summary of the invention
In view of above-mentioned existing in prior technology problem, the object of the present invention is to provide a kind of fast frequency measuring system and method, it is handled measured signal and reference signal by frequency adjuster, the length of testing speech that prolongs measured signal improves the frequency of reference signal simultaneously, frequency tester utilizes the high-frequency count pulse that tested low frequency signal is measured, and realizes high precision, frequency measurement effect fast.
The objective of the invention is to be achieved through the following technical solutions:
The invention provides a kind of fast frequency measuring system, comprising: frequency adjuster, frequency tester and processor controls, wherein,
Frequency adjuster is used for that frequency division is carried out in measured signal and handles, and obtains tested low frequency signal; Reference signal is carried out process of frequency multiplication, obtain the high-frequency count pulse;
Frequency tester links to each other with frequency adjuster, is used to receive tested low frequency signal and high-frequency count pulse from frequency adjuster, utilizes described high-frequency count pulse that tested low frequency signal is measured, and obtains the frequency measurement data;
Processor controls links to each other with frequency tester, is used for to frequency tester output control signal, and the work of control frequency tester, and acquisition is from the frequency measurement data of frequency tester, according to this data computation frequency values.
Described frequency adjuster comprises:
Frequency divider is used for that the frequency division processing is carried out in measured signal and obtains tested low frequency signal; With
Frequency multiplier is used for that reference signal is carried out process of frequency multiplication and obtains the high-frequency count pulse.
Described frequency divider is realized by programmable logic device.
Described frequency tester comprises frequency measuring count-er, and it is used for:
Work under the control of processor controls, the number of accumulative total high-frequency count pulse is when the high-frequency count pulse comes, frequency measuring count-er just adds 1, when the rising edge of measured signal or negative edge arrive, to look-at-me of processor controls output, the count value in the frequency tester of output this moment.
The present invention also provides a kind of fast frequency measuring method, comprising:
A, frequency division is carried out in measured signal handle, obtain tested low frequency signal, reference signal is carried out process of frequency multiplication, obtain the high-frequency count pulse;
B, utilize described high-frequency count pulse that tested low frequency signal is measured, obtain the frequency measurement data, when the high-frequency count pulse comes, frequency measuring count-er just adds 1, when the rising edge of measured signal or negative edge arrive, export a look-at-me, the count value in the output frequency tester at this moment;
C, handle described frequency measurement data, obtain the measured signal frequency values according to look-at-me.
Described steps A specifically comprises:
Measured signal is carried out the frequency division processing and/or reference signal is carried out process of frequency multiplication.
Described step B specifically comprises:
B1, when the high-frequency count pulse comes, and the rising edge of tested low frequency signal or negative edge export a look-at-me to processor controls when arriving, and exports measurement data simultaneously.
Described step C comprises:
When C1, processor controls are whenever received a look-at-me, from frequency tester, read measurement data, calculate the short-term of primary measured signal and/or the value of long run frequency accuracy.
Rising and falling edges t interval time of described tested low frequency signal is: t (t=(N/ (2*f
x)),
Wherein:
f
xFrequency for measured signal;
N is the divide ratio of frequency divider.
Described step C1 comprises: when receiving a look-at-me, then obtain a test data X at every turn
iThe number of representing current count pulse, then twice break period count pulse at interval number be:
ΔX
i＝X
i-X
i-1。
The frequency values of the described measured signal of step C is:
f
x=((Δ X
(i-(M-1))+ ... ..+ Δ X
i) * (1/f
0))/((N/2) * M), wherein:
f
xThe frequency that calculates of expression measured signal;
f
0The frequency of expression count pulse;
N represents the divide ratio of frequency divider;
When M represents to calculate the measured signal frequency, the number of the gap periods t of use.
As seen from the above technical solution provided by the invention, the present invention has realized different frequency signals is carried out high precision, measures fast, make measuring accuracy only relevant with the length of testing speech of count pulse, frequency behind the frequency division of measuring speed and measured signal is relevant, and do not influence the precision of measurement, and cost is low, is easy to realize.
Description of drawings
Fig. 1 is a prior art multi-period synchronizing method measuring principle oscillogram;
Fig. 2 is a fast frequency measuring system configuration diagram of the present invention;
Fig. 3 is a frequency tester fundamental diagram of the present invention;
Fig. 4 is a signal flow graph of the present invention;
Fig. 5 is the operational flowchart of the method for the invention.
Embodiment
Core concept of the present invention provides a kind of fast frequency measuring system and method, it comprises frequency adjuster, frequency tester and processor controls, measured signal and reference signal are handled the length of testing speech that prolongs measured signal through frequency adjuster, improve the frequency of reference signal, utilize the high-frequency count pulse that tested low frequency signal is measured again, reach quick, high-precision frequency measurement purpose.
The invention provides a kind of fast frequency measuring system, with reference to Figure 2 shows that fast frequency measuring system configuration diagram of the present invention, this fast frequency measuring system comprises frequency adjuster 1, frequency tester 3 and processor controls 4; Wherein frequency adjuster 1 is used to adjust the frequency of measured signal and reference signal, the length of testing speech that prolongs measured signal improves the frequency of reference signal simultaneously, this frequency adjuster 1 can be frequency divider 10 and/or frequency multiplier 11, wherein frequency divider 10 is connected with frequency tester 3, being used for that frequency division is carried out in measured signal handles, send the tested low frequency signal that obtains after handling to frequency tester 3, described frequency divider 10 can adopt programmable logic device PLD or FPGA to realize, making the signal behind the frequency division all is as low frequency signals such as 1KHz, 1Hz; Described frequency multiplier 11 is connected with frequency tester 3, be used for that reference signal is carried out process of frequency multiplication and obtain the high-frequency count pulse, send frequency tester 3 to, described frequency multiplier 11 can adopt special frequency doubling device that the reference signal frequency multiplication is arrived higher frequency, the short-term accuracy that can be used to improve survey frequency; Frequency tester 3 is used to finish the measuring operation of frequency, frequency tester 3 also can adopt programmable logic device (PLD or FPGA) to realize, can with the public device of frequency divider, this frequency tester 3 comprises a frequency measuring count-er (not shown), is used for the number of accumulative total high-frequency count pulse; Processor controls 4 is connected with frequency tester 3, is used to control frequency tester 3 work, obtains the frequency measurement data, the calculated rate value.
The principle of work of frequency tester 3 is with reference to shown in Figure 3: processor controls 4 output control signals (Rst) make frequency tester 3 work, frequency tester 3 is tested measured signal (Sig) always, when high-frequency count pulse (Clk_b) comes, frequency measuring count-er just adds 1, when the rising edge of measured signal or negative edge arrive, export a look-at-me (Int_r), export the count value (Cnt_b) in the frequency tester 3 at this moment simultaneously, processor controls 4 is whenever received look-at-me one time, read the one-shot measurement data, can calculate the short-term of primary measured signal and/or the value of long run frequency accuracy, described measurement data is the count value of frequency measuring count-er.
With reference to Figure 4 shows that signal flow graph of the present invention, measured signal is sent to frequency division in the frequency divider 10, simultaneously reference signal is delivered to and carried out process of frequency multiplication in the frequency multiplier 11, the high-frequency count pulse that obtains after low frequency measured signal that obtains behind the frequency division and the frequency multiplication is delivered to and is carried out frequency measurement in the frequency tester 3, in frequency tester 3 test processs, processor controls 4 output control signals are given frequency tester 3, frequency tester 3 output look-at-mes are given processor controls 4, when receiving look-at-me, processor controls 4 from frequency tester 3, reads measurement data, whenever receive once and interrupt that processor controls 4 can be calculated the short-term of acquisition primary measured signal and/or the value of long run frequency accuracy.
The present invention also provides a kind of fast frequency measuring method, and with reference to shown in Figure 5, this method specifically comprises:
Step 10: frequency division and process of frequency multiplication are carried out in measured signal and reference signal, and the length of testing speech that prolongs measured signal improves the frequency of reference signal simultaneously, to improve the precision of short-term test;
Frequency division is carried out in measured signal handle and to handle by measured signal being transported to frequency divider 10, obtain tested low frequency signal afterwards; Reference signal is carried out process of frequency multiplication can be handled by reference signal being transported to frequency multiplier 11, obtains the high-frequency count pulse afterwards;
Step 11: frequency tester 3 utilizes the high-frequency count pulse that tested low frequency signal is carried out frequency measurement;
The high-frequency count pulse that obtains after the tested low frequency signal that obtains behind the above-mentioned frequency division and the frequency multiplication is transported in the frequency tester 3, frequency tester 3 output look-at-mes are given processor controls 4, when receiving look-at-me, processor controls 4 from frequency tester 3, reads measurement data, whenever receive once and interrupt that processor controls 4 is calculated the short-term of primary measured signal and/or the value of long run frequency accuracy;
Step 12: handle test data, obtain the current demand signal frequency values;
Because the look-at-me that receives of processor controls 4 is to be produced by the rising and falling edges behind the measured signal frequency division,, establishes the time interval and be so equate the interval time of this interruption:
t(t＝(N/(2＊f
x))，
f
xBe the frequency of measured signal, N is the divide ratio of frequency divider, and 2 expression rising edges and negative edge are all counted, and when each interruption arrived, processor controls 4 all can be received test data X one time
iThe number of the count pulse in this section time interval is:
ΔX
i＝X
i-X
i-1，
Because the figure place of frequency measuring count-er is limited, can count from zero after frequency measuring count-er reaches maximal value, so there is X
i＜X
I-1Situation, this moment X
iNeed add the maximal value (X that can write down of frequency measuring count-er
M) promptly:
ΔX
i＝(X
i+X
M)-X
i-1；
With the X that obtains
iWith Δ X
iPreserve for follow-up calculating, when the number of pulse is once calculated in every acquisition, can calculate the frequency values fx of current measured signal:
f
x＝((ΔX
(i-(M-1))+...+ΔX
i)＊(1/f
0))/((N/2)＊M)，
Wherein:
f
xThe frequency of expression measured signal;
f
0The frequency of expression count pulse;
N represents the divide ratio of frequency divider;
2 expression rising edges and negative edge are all counted;
When M represents calculated rate, the number of the gap periods t of use, just Δ X participates in the number of calculating.
In the process of whole measurement, frequency tester 3 is in effective state always, and longer when the duration of test, when promptly M was big, the error of ± 1 word just can be eliminated, and along with the increase of M, measuring accuracy can be high more.Because the frequency of count pulse is very high, measuring accuracy just can improve greatly, has saved the test duration (when arriving same precision, the M value is just less) simultaneously.Every a time interval t, will obtain new test data again, just obtain new frequency accuracy data through calculating; Because the time interval t time is shorter, the renewal rate of frequency accuracy is very fast like this, and this can adjust at interval as required during actual the use, like this measuring speed that can obtain to want.In calculation process, get different M values simultaneously, just can obtain the value of a plurality of frequency accuracies of measured signal, realize that short-term, the medium and long term frequency of measured signal accurately measured.
Following table is the complete list of measuring rate and accuracy of measurement, as can be seen from the table:
The precision of test is only relevant with count pulse and length of testing speech, and accuracy of test increases along with the increase of the increase of length of testing speech and count pulse;
Frequency behind the frequency division of measuring speed and measured signal is relevant, and measuring speed does not influence the precision of measurement.This point is very important in measuring at a high speed;
Low frequency and high-frequency signal have identical measuring accuracy and measuring speed under the length of testing speech condition identical with count pulse;
Under the situation of identical measuring speed, synchronization can calculate the frequency accuracy under the different M values, can realize the measurement to the frequency accuracy of short-term, medium and long term like this.
In sum, the present invention has realized the different frequency signals frequency is carried out high precision, measured fast, makes measuring accuracy only relevant with the length of testing speech of count pulse, and the frequency behind the frequency division of measuring speed and measured signal is relevant, and does not influence the precision of measurement.
The above; only for the preferable embodiment of the present invention, but protection scope of the present invention is not limited thereto, and anyly is familiar with those skilled in the art in the technical scope that the present invention discloses; the variation that can expect easily or replacement all should be encompassed within protection scope of the present invention.Therefore, protection scope of the present invention should be as the criterion with the protection domain of claim.
Claims (9)
1, a kind of fast frequency measuring system is characterized in that, comprising: frequency adjuster, frequency tester and processor controls, wherein,
Frequency adjuster is used for that frequency division is carried out in measured signal and handles, and obtains tested low frequency signal; Reference signal is carried out process of frequency multiplication, obtain the high-frequency count pulse;
Frequency tester links to each other with frequency adjuster, is used to receive tested low frequency signal and high-frequency count pulse from frequency adjuster, utilizes described high-frequency count pulse that tested low frequency signal is measured, and obtains the frequency measurement data;
Processor controls links to each other with frequency tester, is used for to frequency tester output control signal, and the work of control frequency tester, and acquisition is from the frequency measurement data of frequency tester, according to this data computation frequency values.
2, fast frequency measuring system as claimed in claim 1 is characterized in that, described frequency adjuster comprises:
Frequency divider is used for that the frequency division processing is carried out in measured signal and obtains tested low frequency signal; With
Frequency multiplier is used for that reference signal is carried out process of frequency multiplication and obtains the high-frequency count pulse.
3, fast frequency measuring system as claimed in claim 2 is characterized in that, described frequency divider is realized by programmable logic device.
4, fast frequency measuring system as claimed in claim 2 is characterized in that, described frequency tester comprises frequency measuring count-er, and it is used for:
Work under the control of processor controls, the number of accumulative total high-frequency count pulse is when the high-frequency count pulse comes, frequency measuring count-er just adds 1, when the rising edge of measured signal or negative edge arrive, to look-at-me of processor controls output, the count value in the frequency tester of output this moment.
5, a kind of fast frequency measuring method is characterized in that, comprising:
A, frequency division is carried out in measured signal handle, obtain tested low frequency signal, reference signal is carried out process of frequency multiplication, obtain the high-frequency count pulse;
B, utilize described high-frequency count pulse that tested low frequency signal is measured, obtain the frequency measurement data, when the high-frequency count pulse comes, frequency measuring count-er just adds 1, when the rising edge of measured signal or negative edge arrive, export a look-at-me, the count value in the output frequency tester at this moment;
C, handle described frequency measurement data, obtain the measured signal frequency values according to look-at-me.
6, fast frequency measuring method as claimed in claim 5 is characterized in that, described step C comprises:
When C1, processor controls are whenever received a look-at-me, from frequency tester, read measurement data, calculate the short-term of primary measured signal and/or the value of long run frequency accuracy.
7, fast frequency measuring method as claimed in claim 5 is characterized in that, rising and falling edges t interval time of described tested low frequency signal is: t (t=(N/ (2*f
x)),
Wherein:
f
xFrequency for measured signal;
N is the divide ratio of frequency divider.
8, as claim 5 or 6 described fast frequency measuring methods, it is characterized in that, described step C1 comprises: when receiving a look-at-me, then obtain the number that a test data Xi represents current count pulse at every turn, then twice break period count pulse at interval number be:
ΔX
i＝X
i-X
i-1。
9, fast frequency measuring method as claimed in claim 8 is characterized in that, the frequency values of the described measured signal of step C is:
f
x=((Δ X
(i-(M-1))+ ... ..+ Δ X
i) * (1/f
0))/((N/2) * M), wherein:
f
xThe frequency that calculates of expression measured signal;
f
0The frequency of expression count pulse;
N represents the divide ratio of frequency divider;
When M represents to calculate the measured signal frequency, the number of the gap periods t of use.
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|---|---|---|---|
| CNB2005101034858A CN100501421C (en) | 2005-09-19 | 2005-09-19 | Fast frequency measuring system and method |
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|---|---|---|---|
| CNB2005101034858A CN100501421C (en) | 2005-09-19 | 2005-09-19 | Fast frequency measuring system and method |
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|---|---|---|---|---|
| CN101026781B (en) * | 2007-01-23 | 2010-12-08 | 宁波大学 | Quasi full-synchronous high-precision rapid frequency measuring device and method |
| CN101871968B (en) * | 2009-04-24 | 2011-12-07 | 郑州威科姆科技股份有限公司 | Reliable time scale pulse measurement method and measurement device thereof |
| JP5517033B2 (en) * | 2009-05-22 | 2014-06-11 | セイコーエプソン株式会社 | Frequency measuring device |
| JP5815918B2 (en) | 2009-10-06 | 2015-11-17 | セイコーエプソン株式会社 | Frequency measuring method, frequency measuring apparatus, and apparatus provided with frequency measuring apparatus |
| CN101692107B (en) * | 2009-10-14 | 2011-05-18 | 张国鹏 | Method for producing high-speed frequency measurement chip |
| CN101819231B (en) * | 2010-03-18 | 2014-08-06 | 天津农学院 | High-resolution frequency measurement method with continuous counting interval marking |
| CN101881796B (en) * | 2010-06-30 | 2013-01-09 | 天津市德力电子仪器有限公司 | Frequency counting module and counting method and application |
| JP5883558B2 (en) | 2010-08-31 | 2016-03-15 | セイコーエプソン株式会社 | Frequency measuring device and electronic device |
| CN102495283B (en) * | 2011-12-09 | 2014-01-15 | 中国人民解放军第二炮兵计量站 | Self-adaptive equal-precision frequency measuring method |
| US10114053B2 (en) * | 2012-10-24 | 2018-10-30 | Abb Schweiz Ag | Pulse frequency measurement device and method and control system |
| CN102981052A (en) * | 2012-11-09 | 2013-03-20 | 苏州市职业大学 | Broadband electronic frequency meter |
| CN103235178A (en) * | 2013-04-26 | 2013-08-07 | 河南科技大学 | Double-button equal-precision frequency meter and calculating method thereof |
| CN103698602B (en) * | 2013-12-16 | 2016-05-18 | 北京自动化控制设备研究所 | A kind of large synchronous cline frequency measuring method of dynamic high precision |
| CN104020349B (en) * | 2014-06-20 | 2016-09-21 | 西南大学 | Based on period tracking method and the signal frequency measuring method of portable number of cycles method |
| CN105629062B (en) * | 2014-11-07 | 2019-05-03 | 北京北广科技股份有限公司 | A kind of frequency detecting method of variable frequency sine-wave |
| CN104931779A (en) * | 2015-05-08 | 2015-09-23 | 中国电子科技集团公司第四十一研究所 | Single-channel realized continuous frequency measure method |
| CN105866542A (en) * | 2016-05-23 | 2016-08-17 | 南京航空航天大学 | High-accuracy sliding frequency measurement method |
| CN106814249A (en) * | 2017-02-28 | 2017-06-09 | 中国科学院国家空间科学中心 | A kind of frequency measurement method for optical pumped magnetometer frequency meter |
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| CN110441597A (en) * | 2019-06-21 | 2019-11-12 | 武汉玉航科技有限公司 | A kind of instantaneous wideband High-accuracy frequency measurement system |
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