CN108417191A - A kind of fender using and measuring adjustmenting management system suitable for music score identification - Google Patents
A kind of fender using and measuring adjustmenting management system suitable for music score identification Download PDFInfo
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Classifications
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- G—PHYSICS
- G10—MUSICAL INSTRUMENTS; ACOUSTICS
- G10H—ELECTROPHONIC MUSICAL INSTRUMENTS; INSTRUMENTS IN WHICH THE TONES ARE GENERATED BY ELECTROMECHANICAL MEANS OR ELECTRONIC GENERATORS, OR IN WHICH THE TONES ARE SYNTHESISED FROM A DATA STORE
- G10H1/00—Details of electrophonic musical instruments
- G10H1/32—Constructional details
- G10H1/34—Switch arrangements, e.g. keyboards or mechanical switches specially adapted for electrophonic musical instruments
- G10H1/344—Structural association with individual keys
-
- G—PHYSICS
- G10—MUSICAL INSTRUMENTS; ACOUSTICS
- G10H—ELECTROPHONIC MUSICAL INSTRUMENTS; INSTRUMENTS IN WHICH THE TONES ARE GENERATED BY ELECTROMECHANICAL MEANS OR ELECTRONIC GENERATORS, OR IN WHICH THE TONES ARE SYNTHESISED FROM A DATA STORE
- G10H1/00—Details of electrophonic musical instruments
- G10H1/36—Accompaniment arrangements
-
- G—PHYSICS
- G10—MUSICAL INSTRUMENTS; ACOUSTICS
- G10H—ELECTROPHONIC MUSICAL INSTRUMENTS; INSTRUMENTS IN WHICH THE TONES ARE GENERATED BY ELECTROMECHANICAL MEANS OR ELECTRONIC GENERATORS, OR IN WHICH THE TONES ARE SYNTHESISED FROM A DATA STORE
- G10H1/00—Details of electrophonic musical instruments
- G10H1/44—Tuning means
Abstract
The invention belongs to fender technical fields, disclose a kind of fender using and measuring adjustmenting management system suitable for music score identification, including：Power module, induction module, main control module, timbre bank module, light emitting module, judgment module, display module.The present invention substitutes the contact switch of conductive rubber by induction module, avoids the defect of caused poor contact, malfunction and cleaning maintenance inconvenience in the case of wet environment, contact wear, crack dust and conductive rubber aging；Sound quality in learner is practiced on the piano by judgment module simultaneously sound quality and timbre bank module carries out comparison judgement automatically, identifies the difference in two kinds of sound quality convenient for learner, to achieve the effect that distinguish sound, improves the learning level of piano.
Description
Technical field
The invention belongs to fender technical field more particularly to a kind of fender using and measuring tune suitable for music score identification
With management system.
Background technology
Currently, the prior art commonly used in the trade is such：
The principle of sound of fender be form electrophoresis using keyboard as on-off switch, once press key, internal crystal oscillator
It starts to work, forms the waveform that pulse generates certain frequency, be then passed through the amplification of frequency divider, be sent into loud speaker sounding.Entirely
Voiced process is by simple frequency dividing analog circuit, so keyboard does not have dynamics and hits string feeling, also more machinery is dull for sound.
However, physical button (such as button made of silica gel) is used for a long time in existing fender, may in the case of contact wear and
Lead to the problem of damage；Over time or in wet condition, ageing of rubber can lead to poor contact to conductive rubber
Or the problem of malfunction；Existing fender is not supported to distinguish that sound is trained simultaneously, can not cultivate judgement of the learner to pitch.
An important factor for short-term frequency stability of signal is gauge signal quality, it directly affects the performance of system,
Phase noise is the important indicator for describing signal short-term frequency stability.Especially in application fields such as radar, communication, navigation,
Reducing phase noise becomes one of the key technology for improving system performance.For example, the direct shadow of phase noise in Doppler radar
Ring the moving-target detection performance of radar；In digital communication, especially phase-modulation communication system, phase noise is to error rate of system
It is all of great significance with the isolation of adjacent channel.Therefore, phase noise measurement has important in modern electronic technology
Using, it has also become one of the research hotspot of Current electronic fields of measurement.According to the Different Extraction Method of phase noise signal, currently
Phase noise measurement method be broadly divided into the methods of direct frequency spectrograph mensuration, Time-of-Flight, frequency-discrimination method, Phase Demodulation.
Directly frequency spectrograph method is a kind of simple and practicable phase noise measurement method, and source signal to be measured is directly inputted to frequency spectrograph by it
Input terminal tunes the carrier frequency of spectrum analyzer, by measuring the frequency spectrum of measured signal, by noise power and carrier power
Ratio simultaneously carries out necessary amendment to calculate the phase noise of measured signal.Frequency spectrograph mensuration is in the application by following factor
Restriction：Measurement result is restricted by frequency spectrograph local vibration source phase noise, cannot distinguish between phase noise and amplitude noise, is not easy to survey
Measure the phase noise at nearly carrier wave.Time-of-Flight is sent into the time after dividing measured source and reference source signal by frequency divider
Poor counter is used to measure the time difference between two signal zero-crossings, and the opposite ginseng of measured source is calculated with the time difference sequence of measurement
Examine the phase noise in source.The signal frequency for being reduced measured source and reference source in this method using frequency divider was improved between the time
Every the resolution ratio of counter measures time difference.The major advantage of this method is that system construction cost is low, is easily achieved；Its limitation
It is that this method is limited by system bandwidth, the phase noise of local oscillator limits measurement effect inside time-interval counter, separately
The outer length that also must be noted that cable and impedance matching.Frequency discrimination mensuration is also known as reference source-free method, it plays the frequency in source to be measured
Volt Δ f is transformed to voltage fluctuation Δ v by certain microwave discriminator, then the relief volume of the voltage is measured with baseband frequency spectrum analyzer,
To realize phase noise measurement.Common frequency discriminator has delay line/mixing type frequency discriminator, RF bridges/Delay line discriminator, cavity
Frequency discriminator, delay line frequency discriminator etc..Its operation principle is as follows：Tested source signal divides two-way through power splitter, prolongs all the way through broadband
Slow line delay, τd, frequency fluctuation is become into the phase fluctuation Δ π of φ=2 f0τd, another way signal is through adaptive-bandwidth phase shifter, adjusting
Phase shifter keeps two input signals orthogonal, is sent into phase discriminator and carries out orthogonal phase demodulation, phase noise is converted to voltage by phase discriminator and is made an uproar
Sound carries out the signal processings such as FFT and power Spectral Estimation after A/D is converted to digital signal, measures the phase noise of measured signal
Power spectrum Sφ(f) and output power single sideband phase noise L (f).The major advantage of frequency discrimination mensuration is without necessarily referring to signal source, to phase
Fluctuating larger measured source has good measurement effect；The disadvantage is that the measured source for different frequency needs to carry out frequency discriminator
It adjusts, be not easy to measure the phase noise at nearly carrier wave.Phase-detect measurement method is also referred to as double source measurement method or phaselocked loop measurement method.
This method is using a double balanced mixer as phase discriminator, by measured signal and a same frequency and orthogonal high stability
Two input signals of the reference source signal as phase discriminator, phase discriminator output is proportional to the phase fluctuation of measured signal
Low-frequency noise voltage is added on frequency spectrograph by low-pass filter and low-noise amplifier and measures different fmThe noise level at place,
The S in measured signal source is calculatedφ(f), it or by the phase detector output signal after low-pass filtering and low noise amplification samples
After transform to numeric field, the single-side belt power spectrum of measured signal is acquired using the method for Digital Signal Processing.Phase Demodulation it is main
Advantage is that measurement sensitivity is high, frequency resolution is high, reference frequency output is wide, has preferable rejection ability to amplitude noise；
The disadvantage is that reference source signal must be equal with measured signal frequency.There are one common features for above-mentioned phase noise measurement method
It is the phase information for being tested source signal to be extracted using special hardware circuit, and the single-side belt phase for analyzing with this measured source is made an uproar
Sound.
Existing phase noise measurement method is all that the phase information in measured signal source is extracted using special hardware circuit,
And the output power single sideband phase noise in measured signal source is analyzed with this, the extraction performance of such phase extraction circuits is largely determined
The performance of phase noise measurement is determined, and the frequency response of phase extraction circuits also can be to measurement result.
The rapid development of wireless communication and super-broadband tech needs very wide frequency band, this makes frequency spectrum more and more crowded.For
Limited spectrum resources are made full use of, there must be a variety of applications in certain frequency bandwidth, meet microwave circuit system to more
The demand of wave band multichannel frequency-selecting.Therefore the technologies such as frequency hopping, spread spectrum, dynamic frequency allocation are developed, and tunable filter is made
Great attention is received for the important devices of these technologies.According to research reports, the structure of tunable filter mainly has micro-strip, hangs root
Set the forms such as line, dielectric resonator, substrate integration wave-guide (SIW).Adjustable realization method mainly has varactor, PIN bis-
Pole pipe, RF MEMS technologies etc..It can be divided into according to the mode of tuning：1, mechanical tuning；2, electric tuning；3, acousto-optic tunable.According to tune
Humorous content can be divided into：1, regulable center frequency filter；2, bandwidth tunable filter；3, centre frequency and bandwidth are adjustable simultaneously
Filter.
Currently, having carried out a series of research work to tunable filter both at home and abroad, and achieve some achievements.But it reports
The filter that road comes out generally is faced with following some defects：
(1) tunable filter is due to generally by controlling the coupling between multistage resonator, being tuned bandwidth so that band
Broad tuning range very little cannot meet the requirement to bandwidth tuning range in practical application.
(2) tunable filter is due to generally using multistage resonator structure, and using coupling input way of output etc., makes
The insertion loss for obtaining filter is larger.
(3) absolute bandwidth of passband changes during centre frequency tunes, and cannot meet frequency in practical application
The requirement that electric timing absolute bandwidth is kept constant.
(4) during being tuned to centre frequency or bandwidth, stable filtering performance cannot be kept, is mainly manifested in
Small when big when return loss and insertion loss, passband ripple is uneven etc. affects the stability of system Whole Response.
There are Insertion Loss in adjustable process for existing variable band-pass filter greatly, absolute bandwidth changes, filtering characteristic is unstable
The problem of.
In conclusion problem of the existing technology is：
Physical button (such as button made of silica gel) is used for a long time in existing fender, may be in the case of contact wear
And lead to the problem of damage；Over time or in wet condition, ageing of rubber can lead to contact not to conductive rubber
The problem of good or malfunction；Existing fender is not supported to distinguish that sound is trained simultaneously, can not cultivate judgement of the learner to pitch；
Measurement result accuracy existing for frequency response of the existing phase noise measurement method using phase extraction circuits
It is relatively low；
There are Insertion Loss in adjustable process for existing variable band-pass filter greatly, absolute bandwidth changes, filtering characteristic is unstable.
Invention content
In view of the problems of the existing technology, the present invention provides a kind of fender using and measurings suitable for music score identification
Adjustmenting management system.
The invention is realized in this way a kind of fender using and measuring adjustmenting management system suitable for music score identification, is fitted
For music score identification fender using and measuring adjustmenting management system include：
Induction module is connect with main control module, is sent out for receiving the touch signal generated on fingerboard, and by the signal
It is sent to main control module and carries out processing analysis；
The induction module is by the Power Spectrum Model of oscillator signal, and using signal power spectral measurement data, use is non-
Linear least square carries out curve fitting, and obtains the initial parameter values in Power Spectrum Model, and writes canonical systems to parameter
It is modified, finally obtains the parameter for meeting given requirements；Further according to the pass of power spectrum signal and its phase noise power law model
The parameter acquired is substituted into phase noise power law model, and then obtains the phase noise measurement result of measured signal by system；
Main control module connects with power module, induction module, timbre bank module, light emitting module, judgment module, display module
It connects, for controlling scheduling modules work；
Timbre bank module is connect with main control module, for storing tamber data；
Judgment module is connect with main control module, and the pitch for choosing learner is carried out with the pitch that controller is chosen
It compares, if pitch is corresponding, judgment module is shown correctly by output device, if conversely, pitch does not correspond to, judgment module is logical
It crosses display module and shows mistake；
The oscillator is provided with by input microstrip line, input matching tuning network, resonator, output matching tuning net
Network, output microstrip line are sequentially connected the upper-layer micro-strip structure of composition；
By inputting microstrip line and exporting feed microstrip line to resonator, input matching tuning network and output input matching
Tuning network realizes the matching with resonator, meets required External Q, ensures that absolute bandwidth is constant, filters in adjustable process
Wave property is stablized；Input matching tuning network and output input matching tuning network are made of varactor, are separately connected defeated
Enter to export microstrip line and resonator；
Micro-strip resonantor, input microstrip line, output microstrip line are printed on the medium substrate of bandpass filter middle layer.
Further, input microstrip line and output microstrip line are 50 Ω microstrip lines；
Resonator is by half wave microstrip line load T-type open circuit minor matters, wherein half wave microstrip line both ends
The first varactor and the second varactor are loaded respectively；The both ends of the horizontal microstrip line of T-type open circuit minor matters load respectively
Third varactor and the 4th varactor；
Setting input matching tuning network between the input microstrip line resonator, input matching tuning network is by the
One varactor and the 5th varactor composition；
Setting output matching tuning network between the resonator and output microstrip line, output matching tuning network is by the
Two varactors and the 6th varactor composition；
First varactor, the second varactor, third varactor, the 4th varactor, the 5th
Varactor and the 6th varactor are respectively provided with biasing circuit；
The first capacitance and the 5th varactor are loaded respectively between input microstrip line and the resonator；It is described humorous
It shakes and loads the 6th varactor and the second capacitance respectively between device and output microstrip line；Five varactors and first every
Straight capacitance, the 6th varactor and the second capacitance are cascaded by the rectangular microband paste that the length of side is 0.7mm；
Half wave microstrip line and T-type the open circuit minor matters of resonator carry out certain bending, whole to reduce size
Axisymmetricly structure.
Further, it is specifically included using the method that nonlinear least square method determines initial parameter values：
According to formulaUsing nonlinear least square method, determines the initial value of parameter, take(β=0,1,2,3,4) needs to select aβInitial value, by formulaIt is expressed as
Matrix form：
FA=S；
Wherein：
A=[a0 a1 … a4]TS=[S0 S1 … S4]T；
Data point in matrix F is from N number of { (fi,Si) i=1, five Frequency points are chosen in 2 ..., N, are chosen
Numerical value should ensure that matrix F is that full rank is reversible；
Thus expression parameter a is obtainedβThe initial value of the matrix A of initial value is：
WithIt is iterated for initial value and the value of matrix A is estimated, l expressions change
Generation number, at this time l=0；
The error of parameter Estimationβ=0,1 ..., 4,It is estimated by following equation：
Wherein coefficientWithFor：
Wherein SkIndicate frequency fkThe power spectrum measurement value at place,Indicate frequency fkLocate corresponding power spectrum the l times changes
Generation value, i.e.,：
Noise model parameters estimation judgment method be：
JudgeError requirements are such as unsatisfactory for, are enabled：
L=l+1；
And it will be revisedWith corresponding power spectrum measurement dataIt substitutes into canonical systems to be solved, obtain each
The correction value of parameterβ=0,1 ... 4, it rejudgesUntil errorMeet measurement request or reaches changing for setting
Generation number.
Meet error requirements, then by parameter valueAsThe value of (β=0,1,2,3,4) substitutes into formulaIn to get to the phase noise of measured signal, and thus paint
Phase noise curve processed.
Further, the induction module includes：
Power spectrum data acquisition module, major function are the acquisitions completed to input signal power modal data, for follow-up ginseng
Number estimation provides data source.
Parameter calculating module, major function are estimated the parameter in input signal power spectrum model, finally obtain
Meet the parameter value of error requirements.
Phase noise measurement result-generation module, major function are by the way that finally obtained parameter substitution signal phase is made an uproar
The phase noise measurement result of tested oscillator signal is calculated in sound power law model.
Further, the fender using and measuring adjustmenting management system suitable for music score identification includes：
Power module is connect with main control module, for being powered to fender；
Light emitting module is connect with main control module, for calling corresponding sound after decoding touch signal according to main control module
Color sends out corresponding low level signal, prompts currently selected tone color；
Display module is connect with main control module, for showing judgment module judging result data information.
Further, induction module inducing method is as follows：
First, induction module receives the touch signal generated on fingerboard, and sends the signal to main control module；
Then, main control module calls corresponding tone color after decoding the touch signal received,
Finally, main control module scheduling light emitting module sends out corresponding low level signal, prompts currently selected tone color.
Advantages of the present invention and good effect are：
The present invention substitutes the contact switch of conductive rubber by induction module, avoid wet environment, contact wear,
The defect of caused poor contact, malfunction and cleaning maintenance inconvenience in the case of crack dust and conductive rubber aging；Together
When learner is practiced on the piano by judgment module sound quality and timbre bank module in sound quality carry out comparison judgement automatically, be convenient for
Learner identifies the difference in two kinds of sound quality, to achieve the effect that distinguish sound, improves the learning level of piano.
The present invention does not use the phase information of hardware phase noise extraction circuit extraction measured signal, but utilizes oscillation
The relationship of device power spectrum signal and its phase noise power law spectrum model realizes that parameter calculates by nonlinear least square method, from
And oscillator signal phase noise measurement is realized based on phase noise mathematical model.The method of the present invention is relative to existing phase
The main advantage of noise measuring method is the influence for having avoided hardware phase noise extraction circuit to measurement performance.The side of the present invention
Method is to have avoided hardware phase noise extraction circuit to measurement performance relative to the main advantage of existing phase noise measurement method
Influence.
The oscillator of induction module of the present invention, upper layer use microstrip structure；Using the transfiguration two for making T-type open circuit minor matters both ends
The symmetrically placed mode of pole pipe shares ground hole and biasing circuit, reduces DC control circuit, keeps its control simple；Resonator with
Constant capacitance between input-output line plays blocking；The half wave microstrip line and T-type minor matters of resonator are closed
Suitable bending, is reduced in size, and whole is in symmetrical structure；The complete adjustable of frequency and bandwidth is realized, in the frequency of wider range
Absolute bandwidth is kept constant in adjustable process, and centre frequency is kept constant in the bandwidth adjustable process of wider range, ensures frequency
Filtering characteristic is stablized in rate adjustable process.
Compared with prior art, the invention has the advantages that：
1. the present invention uses microstrip structure, compact to design, processing is simple, of low cost, is easily integrated.
2. the present invention is during bandwidth tuning, centre frequency remains unchanged, and absolute bandwidth adjustable range is 150MHz-
It is adjustable to realize wide scope bandwidth by 460MHz.
3. electrically tunable filter of the present invention is in wider centre frequency tuning range, filter characteristic is highly stable, inserts
Enter loss and be maintained at 0.85dB or so, return loss is maintained at 25dB or so.
4. the present invention is electrically tunable filter in wider centre frequency tuning range, absolute bandwidth can still be kept substantially
It is constant, meet for the constant requirement of absolute bandwidth.
5. the present invention uses the load input and output between resonator and input/output terminal to match tuning network, convenient, flexible
Tuning feeding network and resonator between impedance matching, provide tunable External Q, meeting frequency, bandwidth can timing pair
Matched requirement.
6. can according to actual demand carry out adaptive impovement, by change resonator length, varactor model come
Resonant operational frequency range is adjusted, meets the needs of different frequency range communication standard.
Description of the drawings
Fig. 1 is the fender using and measuring adjustmenting management system structure provided in an embodiment of the present invention suitable for music score identification
Block diagram.
In figure：1, power module；2, induction module；3, main control module；4, timbre bank module；5, light emitting module；6, judge
Module；7, display module.
Fig. 2 is that the experiment curv of measured signal power spectrum is illustrated with matched curve in embodiment provided in an embodiment of the present invention
Figure.
Fig. 3 is the measurement result of the method for the present invention measurement result and AV4036F in embodiment provided in an embodiment of the present invention
Comparison schematic diagram.
Fig. 4 is theory structure schematic diagram provided in an embodiment of the present invention.
Fig. 5 is matching tuning network schematic diagram provided in an embodiment of the present invention.
Fig. 6 is matching tuning network schematic equivalent circuit provided in an embodiment of the present invention.
Specific implementation mode
In order to further understand the content, features and effects of the present invention, the following examples are hereby given, and coordinate attached drawing
Detailed description are as follows.
Physical button (such as button made of silica gel) is used for a long time in existing fender, may be in the case of contact wear
And lead to the problem of damage；Over time or in wet condition, ageing of rubber can lead to contact not to conductive rubber
The problem of good or malfunction；Existing fender is not supported to distinguish that sound is trained simultaneously, can not cultivate judgement of the learner to pitch.
As shown in Figure 1, the fender using and measuring adjustmenting management system provided in an embodiment of the present invention suitable for music score identification
System includes：Power module 1, induction module 2, main control module 3, timbre bank module 4, light emitting module 5, judgment module 6, display module
7。
Power module 1 is connect with main control module 3, for being powered to fender；
Induction module 2 is connect with main control module 3, for receiving the touch signal generated on fingerboard, and by the signal
It is sent to main control module 3 and carries out processing analysis；
Main control module 3, with power module 1, induction module 2, timbre bank module 4, light emitting module 5, judgment module 6, display
Module 7 connects, for controlling scheduling modules work；
Timbre bank module 4 is connect with main control module 3, for storing tamber data；
Light emitting module 5 is connect with main control module 3, corresponding for being called after being decoded touch signal according to main control module 3
Tone color sends out corresponding low level signal, prompts currently selected tone color；
Judgment module 6 is connect with main control module 3, the pitch that the pitch for choosing learner and controller are chosen into
Row compares, if pitch is corresponding, judgment module is shown correctly by output device, if conversely, pitch does not correspond to, judgment module
Mistake is shown by display module 7；
Display module 7 is connect with main control module 3, for showing 6 judging result data information of judgment module.
2 inducing method of induction module provided by the invention is as follows：
First, induction module receives the touch signal generated on fingerboard, and sends the signal to main control module；
Then, main control module calls corresponding tone color after decoding the touch signal received,
Finally, main control module scheduling light emitting module sends out corresponding low level signal, prompts currently selected tone color.
The present invention is in use, be powered fender by power module 1；Then, piano is received by induction module 2
The touch signal generated on keyboard, and send the signal to main control module 3 and carry out processing analysis；Main control module 3 is from bank
Corresponding tone color is called after the decoding of 4 touch signal of module；And corresponding low level signal is sent out by light emitting module 5, prompt is worked as
Preceding selected tone color；The pitch that learner chooses is compared with the pitch that controller is chosen by judgment module 6, if sound
High corresponding, judgment module is shown correctly by output device, if conversely, pitch does not correspond to, judgment module is by showing mould
Block 7 shows mistake.
The induction module is by the Power Spectrum Model of oscillator signal, and using signal power spectral measurement data, use is non-
Linear least square carries out curve fitting, and obtains the initial parameter values in Power Spectrum Model, and writes canonical systems to parameter
It is modified, finally obtains the parameter for meeting given requirements；Further according to the pass of power spectrum signal and its phase noise power law model
The parameter acquired is substituted into phase noise power law model, and then obtains the phase noise measurement result of measured signal by system；
The oscillator is provided with by input microstrip line, input matching tuning network, resonator, output matching tuning net
Network, output microstrip line are sequentially connected the upper-layer micro-strip structure of composition；
By inputting microstrip line and exporting feed microstrip line to resonator, input matching tuning network and output input matching
Tuning network realizes the matching with resonator, meets required External Q, ensures that absolute bandwidth is constant, filters in adjustable process
Wave property is stablized；Input matching tuning network and output input matching tuning network are made of varactor, are separately connected defeated
Enter to export microstrip line and resonator；
Micro-strip resonantor, input microstrip line, output microstrip line are printed on the medium substrate of bandpass filter middle layer.
It is 50 Ω microstrip lines to input microstrip line and output microstrip line；
Resonator is by half wave microstrip line load T-type open circuit minor matters, wherein half wave microstrip line both ends
The first varactor and the second varactor are loaded respectively；The both ends of the horizontal microstrip line of T-type open circuit minor matters load respectively
Third varactor and the 4th varactor；
Setting input matching tuning network between the input microstrip line resonator, input matching tuning network is by the
One varactor and the 5th varactor composition；
Setting output matching tuning network between the resonator and output microstrip line, output matching tuning network is by the
Two varactors and the 6th varactor composition；
First varactor, the second varactor, third varactor, the 4th varactor, the 5th
Varactor and the 6th varactor are respectively provided with biasing circuit；
The first capacitance and the 5th varactor are loaded respectively between input microstrip line and the resonator；It is described humorous
It shakes and loads the 6th varactor and the second capacitance respectively between device and output microstrip line；Five varactors and first every
Straight capacitance, the 6th varactor and the second capacitance are cascaded by the rectangular microband paste that the length of side is 0.7mm；
Half wave microstrip line and T-type the open circuit minor matters of resonator carry out certain bending, whole to reduce size
Axisymmetricly structure.
It is specifically included using the method that nonlinear least square method determines initial parameter values：
According to formulaUsing nonlinear least square method, determines the initial value of parameter, take(β=0,1,2,3,4) needs to select aβInitial value, by formulaIt is expressed as
Matrix form：
FA=S；
Wherein：
A=[a0 a1 … a4]TS=[S0 S1 … S4]T；
Data point in matrix F is from N number of { (fi,Si) i=1, five Frequency points are chosen in 2 ..., N, are chosen
Numerical value should ensure that matrix F is that full rank is reversible；
Thus expression parameter a is obtainedβThe initial value of the matrix A of initial value is：
WithIt is iterated for initial value and the value of matrix A is estimated, l expressions change
Generation number, at this time l=0；
The error of parameter Estimationβ=0,1 ..., 4,It is estimated by following equation：
Wherein coefficientWithFor：
Wherein SkIndicate frequency fkThe power spectrum measurement value at place,Indicate frequency fkLocate corresponding power spectrum the l times changes
Generation value, i.e.,：
Noise model parameters estimation judgment method be：
JudgeError requirements are such as unsatisfactory for, are enabled：
L=l+1；
And it will be revisedWith corresponding power spectrum measurement dataIt substitutes into canonical systems to be solved, obtain each
The correction value of parameterβ=0,1 ... 4, it rejudgesUntil errorMeet measurement request or reaches changing for setting
Generation number.
Meet error requirements, then by parameter valueAsThe value of (β=0,1,2,3,4) substitutes into formulaIn to get to the phase noise of measured signal, and thus paint
Phase noise curve processed.
With reference to specific embodiment, the invention will be further described.
It applies in example, measured signal carrier frequency is 800MHz.The work(of measured signal is measured with spectrum analyzer AV4036F
Rate is composed, and is calculated the phase noise of measured signal according to the method for the present invention using the power spectrum data of measurement, is provided phase noise
Measurement result.And it is the phase noise measurement result of inventive algorithm and the phase noise measurement module of utilization AV4036F is direct
The result of measurement is compared, to illustrate the implementation process and validity of the method for the present invention.
Fig. 2 gives using the spectrum analyzer AV4036F measured signal power spectrum curves measured and utilizes the power spectrum
Measurement data carries out the result of Non-linear least-square curve fitting.The measured signal phase noise coefficient obtained by fitting result
For：
The parameter value that above-mentioned fitting is obtained, you can obtain the output power single sideband phase noise of measured signal.Fig. 3, which gives, utilizes this
The measured signal phase that the phase noise measurement module of measured signal phase noise and AV4036F that inventive method measures measures is made an uproar
The measurement result of sound compares.Table 1 lists the phase noise and frequency that the method for the present invention measures at some frequency deviations in the embodiment
The numerical value for the phase noise that spectrum analysis instrument AV4036F phase noise measurement modules measure compares and error.
The measurement result that the method for the invention obtains in following table embodiment is compared with the data of AV4036F measurement results
As shown in figure 4, the resonator of the present invention is half wave microstrip line load T-type open circuit detail.Y1, L1It indicates
The admittance of half wave microstrip line and physical length, both ends load varactor Cv1；Y2, L2Indicate the T-type branch of load
The admittance of the longitudinal microstrip line of section and physical length；Y3, L3Indicate admittance and the physical length of the T-type detail transverse direction microstrip line of load,
Both ends load varactor Cv2.Axisymmetricly structure, progress even and odd mode analysis can obtain parity mode admittance difference to the resonator
For：
Yin_odd, Yin_evenParity mode admittance is indicated respectively, wherein：
Ys=Y1tan(βL1){Y2[Y3-ωeventan(βL3)]-2Y3tan(βL2)[ωCv2+Y3tan(βL3)]} (4)
According to condition of resonance, parity mode resonant frequency can be expressed as：
It can be obtained by formula (5) (6), foddDepending on Cv1Variation, fevenDepending on Cv1And Cv2Variation, that is, tune
Cv1It can cause the variation of frequency and bandwidth simultaneously.If fixed Cv1, then foddAlso it will fix, fevenTuning only rely in
Cv2.This characteristic is applied to realize the tuning to bandwidth.
θ1=-tan-1[(2Y2/B')/(Y1/Y2-Y2/Y1-Y1Y2/B'2)] (9)
θ2=-tan-1[(2Y1/B')/(Y2/Y1-Y1/Y2-Y1Y2/B'2)] (10)
B'=(B-1/X) (11)
Qe=b/ (J01 2/Y0) (12)
Wherein, b is the Slope Parameters of resonator.
It can be obtained by (7)：In order to reach constant absolute bandwidth, external sort factor will increase with the increase of centre frequency
Greatly.As shown in figure 5, it is to pass through varactor that input and output microstrip line matches tuning network with the input and output between resonator
Cv1、CeCome what is realized, equivalent circuit diagram is as shown in fig. 6, varactor CeIt is Y to be equivalent to admittance1, electrical length θ1One
Section microstrip line series connection one variable susceptance jB, varactor Cv1It is Y to be equivalent to a variable reactance jX one section of admittance in parallel2、
Electrical length is θ2Microstrip line；Variable susceptance jB and variable reactance jX compositions can be changed susceptance jB', can be with according to formula (8) (12)
It obtains, the jB' of variation corresponds to the J of variation01, the Q to be changede, with external component prime factor during satisfaction tuning
It needs.θ can be obtained in conjunction with formula (9) (10)1And θ2Value, and electrical length be θ1And θ2Two sections of microstrip lines it is defeated respectively
Enter to export microstrip line resonator to be absorbed.After the frequency tuning range of resonator determines, so that it may to select suitable capacitance
Value, this tunable network can realize the external sort factor Q required by given bandwidthe。
The above is only the preferred embodiments of the present invention, and is not intended to limit the present invention in any form,
Every any simple modification made to the above embodiment according to the technical essence of the invention, equivalent variations and modification, belong to
In the range of technical solution of the present invention.
Claims (6)
1. a kind of fender using and measuring adjustmenting management system suitable for music score identification, which is characterized in that be suitable for music score and know
Other fender using and measuring adjustmenting management system includes：
Induction module is connect with main control module, for receiving the touch signal generated on fingerboard, and is sent the signal to
Main control module carries out processing analysis；
The induction module is by the Power Spectrum Model of oscillator signal, and using signal power spectral measurement data, use is non-linear
Least square method carries out curve fitting, and obtains the initial parameter values in Power Spectrum Model, and writes canonical systems and carried out to parameter
It corrects, finally obtains the parameter for meeting given requirements；It, will further according to the relationship of power spectrum signal and its phase noise power law model
The parameter acquired substitutes into phase noise power law model, and then obtains the phase noise measurement result of measured signal；
Main control module is connect with power module, induction module, timbre bank module, light emitting module, judgment module, display module, is used
In control scheduling modules work；
Timbre bank module is connect with main control module, for storing tamber data；
Judgment module is connect with main control module, and the pitch for choosing learner is compared with the pitch that controller is chosen,
If pitch is corresponding, judgment module is shown correctly by output device, if conversely, pitch does not correspond to, judgment module passes through aobvious
Show that module shows mistake；
The oscillator is provided with by input microstrip line, input matching tuning network, resonator, exports matching tuning network, defeated
Go out the upper-layer micro-strip structure that microstrip line is sequentially connected composition；
By inputting microstrip line and exporting feed microstrip line to resonator, input matching tuning network and output input matching tuning
The matching of real-time performance and resonator meets required External Q, ensures that absolute bandwidth is constant, filtering is special in adjustable process
Property stablize；Input matching tuning network and output input matching tuning network are made of varactor, and it is defeated to be separately connected input
Go out microstrip line and resonator；
Micro-strip resonantor, input microstrip line, output microstrip line are printed on the medium substrate of bandpass filter middle layer.
2. the fender using and measuring adjustmenting management system suitable for music score identification as described in claim 1, which is characterized in that defeated
It is 50 Ω microstrip lines to enter microstrip line and output microstrip line；
Resonator by half wave microstrip line load T-type open circuit minor matters, distinguish by wherein half wave microstrip line both ends
Load the first varactor and the second varactor；The both ends of the horizontal microstrip line of T-type open circuit minor matters load third respectively
Varactor and the 4th varactor；
Setting input matching tuning network between the input microstrip line resonator, input matching tuning network is become by first
Hold diode and the 5th varactor composition；
Setting output matching tuning network between the resonator and output microstrip line, output matching tuning network is become by second
Hold diode and the 6th varactor composition；
First varactor, the second varactor, third varactor, the 4th varactor, the 5th transfiguration
Diode and the 6th varactor are respectively provided with biasing circuit；
The first capacitance and the 5th varactor are loaded respectively between input microstrip line and the resonator；The resonator
The 6th varactor and the second capacitance are loaded respectively between output microstrip line；Five varactors and the first blocking electricity
Hold, the 6th varactor and the second capacitance are cascaded by the rectangular microband paste that the length of side is 0.7mm；
Half wave microstrip line and T-type the open circuit minor matters of resonator carry out certain bending, and to reduce size, whole is in axis
Symmetrical structure.
3. the fender using and measuring adjustmenting management system suitable for music score identification as described in claim 1, which is characterized in that adopt
It is specifically included with the method that nonlinear least square method determines initial parameter values：
According to formulaUsing nonlinear least square method, determines the initial value of parameter, takeIt needs to select aβInitial value, by formulaIt is expressed as
Matrix form：
FA=S；
Wherein：
A=[a0 a1 … a4]TS=[S0 S1 … S4]T；
Data point in matrix F is from N number of { (fi,Si) i=1, five Frequency points, the number of selection are chosen in 2 ..., N
Value should ensure that matrix F is that full rank is reversible；
Thus expression parameter a is obtainedβThe initial value of the matrix A of initial value is：
WithIt is iterated for initial value and the value of matrix A is estimated, l indicates iteration time
It counts, at this time l=0；
The error of parameter Estimation It is estimated by following equation：
Wherein coefficientWithFor：
Wherein SkIndicate frequency fkThe power spectrum measurement value at place,Indicate frequency fkLocate the l times iterative value of corresponding power spectrum,
I.e.：
Noise model parameters estimation judgment method be：
JudgeError requirements are such as unsatisfactory for, are enabled：
L=l+1；
And it will be revisedWith corresponding power spectrum measurement dataIt substitutes into canonical systems to be solved, obtains each parameter
Correction valueIt rejudgesUntil errorMeet measurement request or reaches the iteration time of setting
Number.
Meet error requirements, then by parameter valueAsValue substitute into formulaIn to get to the phase noise of measured signal, and thus paint
Phase noise curve processed.
4. the fender using and measuring adjustmenting management system suitable for music score identification as described in claim 1, which is characterized in that institute
Stating induction module includes：
Power spectrum data acquisition module, major function are to complete to the acquisition of input signal power modal data, are estimated for subsequent parameter
Meter provides data source.
Parameter calculating module, major function are estimated the parameter in input signal power spectrum model, and satisfaction is finally obtained
The parameter value of error requirements.
Phase noise measurement result-generation module, major function are by the way that finally obtained parameter is substituted into signal phase noise power
The phase noise measurement result of tested oscillator signal is calculated in rule model.
5. the fender using and measuring adjustmenting management system suitable for music score identification as described in claim 1, which is characterized in that institute
It states and includes suitable for the fender using and measuring adjustmenting management system of music score identification：
Power module is connect with main control module, for being powered to fender；
Light emitting module is connect with main control module, for calling corresponding tone color after decoding touch signal according to main control module, is sent out
Go out corresponding low level signal, prompts currently selected tone color；
Display module is connect with main control module, for showing judgment module judging result data information.
6. the fender using and measuring adjustmenting management system suitable for music score identification as described in claim 1, which is characterized in that sense
Answer module inducing method as follows：
First, induction module receives the touch signal generated on fingerboard, and sends the signal to main control module；
Then, main control module calls corresponding tone color after decoding the touch signal received,
Finally, main control module scheduling light emitting module sends out corresponding low level signal, prompts currently selected tone color.
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN109490228A (en) * | 2018-11-09 | 2019-03-19 | 广东水利电力职业技术学院（广东省水利电力技工学校） | A kind of server cabinet control system and control method |
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Application publication date: 20180817 Assignee: Yiyang Sunshine Music Center Assignor: Hunan City University Contract record no.: X2023980043236 Denomination of invention: An impromptu accompaniment allocation management system for electric piano suitable for music score recognition Granted publication date: 20220405 License type: Exclusive License Record date: 20231016 |