CN101614545A - Resonance type optical fiber gyro signal detecting device based on coordinate rotation digital computer algorithm - Google Patents

Abstract

The invention discloses a kind of resonance type optical fiber gyro signal detecting device based on coordinate rotation digital computer algorithm.Detection method comprises the generation of modulation signal and the demodulation method of signal, all adopts based on the phase/amplitude modular converter of coordinate rotation digital computer algorithm and realizes.Pick-up unit comprises laser instrument, coupling mechanism, phase-modulator, optical fiber circulator, photodetector, field programmable gate array chip, D/A, A/D converter, signal sampling passage, feedback circuit, signal output channels.The present invention uses coordinate rotation digital computer algorithm, by the monolithic field programmable gate array chip realize the two-way modulation signal generation, separate the mediation signal Processing, the amplitude of programmable configuration modulation signal, phase place and frequency, be beneficial to the stable and integrated of detection system, arithmetic accuracy is by iterations and data word length decision; The employing optical fiber circulator is avoided the light wave return laser light device in the fiber optic loop, influences laser stability.

Description

Resonance type optical fiber gyro signal detecting device based on coordinate rotation digital computer algorithm

Technical field

The present invention relates to a kind of resonance type optical fiber gyro signal detecting device based on coordinate rotation digital computer algorithm.

Background technology

(Resonator Fiber Optic Gyro is to utilize optics Sagnac effect to realize a kind of high-precision inertia sensing device that detects rotating R-FOG) to resonant cavity optical fiber gyroscope.Because the Sagnac effect is a kind of very faint effect, signal modulation and detection technique have important status in the system.Testing circuit commonly used is made up of modulation signal generator and analogue demodulated signal.With respect to the analog detection system, high, the flexible design of digital detection system stability can effectively suppress the drift noise that 1/f noise and temperature etc. cause.

Direct Digital frequency synthesis (Direct Digital Frequency Synthesis, DDS) key of technology is the phase/amplitude conversion portion, method commonly used has storer (Read-Only Memory, ROM) look-up table, Taylor series method, CORDIC (Coordinate Rotation Digital Computer, CORDIC) algorithm etc.The required ROM of ROM look-up table table capacity is exponential increase with the raising of accuracy requirement, and (Field Programmable Gate Array realizes in FPGA) to be not easy at the scene programmable gate array chip.Along with the raising of integrated circuit level, high-precision frequency synthesis technique can replace the ROM look-up table configuration with real-time calculating.The Taylor series method also is not easy to realize in FPGA owing to using a large amount of multiplyings.Coordinate rotation digital computer algorithm was proposed by J.Volder in nineteen fifty-nine, by add/subtract, shift operation can finish the conversion of high-precision phase-magnitude, be highly suitable among the FPGA and realize.

At the R-FOG system, the method based on the digital input of coordinate rotation digital computer algorithm has been proposed.Can realize the generation of modulation signal, the synchronous demodulation and the digital signal processing of signal simultaneously by the monolithic field programmable gate array chip, make the R-FOG detection system stable more, flexible.

Summary of the invention

The purpose of this invention is to provide a kind of resonance type optical fiber gyro signal detecting device based on coordinate rotation digital computer algorithm.

Be connected with first coupling mechanism, first phase-modulator, first optical fiber circulator, second coupling mechanism, second optical fiber circulator, second phase-modulator, first coupling mechanism based on the laser instrument in the signal supervisory instrument of the resonance type optical fiber gyro of coordinate rotation digital computer algorithm; First phase-modulator is connected with first D/A; Second phase-modulator is connected with second D/A; First optical fiber circulator is connected with first photodetector, the first signal sampling passage, first A/D converter; Second optical fiber circulator is connected with second photodetector, secondary signal sampling channel, second A/D converter; Second coupling mechanism is connected with fiber loop; The 3rd D/A is connected with feedback circuit, laser instrument; The 4th D/A is connected with the gyro signal output channel; Field programmable gate array chip is connected with first D/A, second D/A, the 3rd D/A, the 4th D/A, first A/D converter, second A/D converter respectively.

The circuit of described signal sampling passage is: the positive input terminal of first operational amplifier is as signal input part, the negative input end of first operational amplifier is connected with the output terminal of first operational amplifier, and the output terminal of first operational amplifier is connected with an end of first electric capacity; The other end of first electric capacity is connected with an end of first resistance, second resistance, the other end ground connection of first resistance; The positive input terminal of second operational amplifier is connected with the other end of second resistance, the negative input end of second operational amplifier is connected with an end of the 3rd resistance, the 4th resistance, the output terminal of second operational amplifier is connected the other end ground connection of the 3rd resistance with the other end of the 4th resistance, an end of second electric capacity; The other end of second electric capacity is connected with an end of the 5th resistance, an end of the 3rd electric capacity, and the other end of the 3rd electric capacity is connected the other end ground connection of the 6th resistance with an end of the 6th resistance, the positive input terminal of the 3rd operational amplifier; The negative input end of the 3rd operational amplifier is connected with an end of the 7th resistance, an end of the 8th resistance, the output terminal of the 3rd operational amplifier is connected the other end ground connection of the 7th resistance with the other end of the 5th resistance, the other end of the 8th resistance, an end of the 9th resistance; The other end of the 9th resistance is connected with an end of the tenth resistance, an end of the 4th electric capacity; The positive input terminal of four-operational amplifier is connected with the other end of the tenth resistance, an end of the 5th electric capacity, the negative input end of four-operational amplifier is connected with an end of the 11 resistance, an end of the 12 resistance, the output terminal of four-operational amplifier is connected with the other end of the 4th electric capacity, the other end of the 12 resistance, the other end ground connection of the other end of the 11 resistance, the 5th electric capacity.

The circuit of described feedback circuit is: an end of the 13 resistance is as input end, and the other end of the 13 resistance is connected with an end of the 6th electric capacity, an end of the 14 resistance; The positive input terminal of the 5th operational amplifier is connected with an end of the other end of the 14 resistance, the 7th electric capacity, the negative input end of the 5th operational amplifier is connected with an end of the 15 resistance, an end of the 16 resistance, the output terminal of the 5th operational amplifier is connected the other end ground connection of the other end of the 15 resistance, the 7th electric capacity with the other end of the 6th electric capacity, the other end of the 16 resistance, an end of the 17 resistance; The positive input terminal of the 6th operational amplifier is connected with an end of the 18 resistance, the negative input end of the 6th operational amplifier is connected with the other end of the 17 resistance, an end of the 19 resistance, the output terminal of the 6th operational amplifier is connected with the other end of the 19 resistance, an end of the 22 resistance, the other end ground connection of the 18 resistance; The positive input terminal of the 7th operational amplifier is connected with an end of the 21 resistance, the negative input end of the 7th operational amplifier is connected with the other end of the 22 resistance, an end of the 23 resistance, an end of the 25 resistance, the output terminal of the 7th operational amplifier is connected with the other end of the 25 resistance, the other end ground connection of the 21 resistance; The other end of the 23 resistance is connected with an end of the 20 resistance, an end of the 24 resistance, and the other end of the 20 resistance is connected with power supply, the other end ground connection of the 24 resistance.

The circuit of described gyro signal output channel is: an end of the 26 resistance is as input end, and the other end of the 26 resistance is connected with an end of the 8th electric capacity, an end of the 27 resistance; The positive input terminal of the 8th operational amplifier is connected with an end of the other end of the 27 resistance, the 9th electric capacity, the negative input end of the 8th operational amplifier is connected with an end of the 28 resistance, an end of the 29 resistance, the output terminal of the 8th operational amplifier is connected with the other end of the 8th electric capacity, the other end of the 29 resistance, the other end of the 9th electric capacity, the other end ground connection of the 28 resistance.

The beneficial effect that the present invention has:

1 the present invention uses based on coordinate rotation digital computer algorithm, and by the generation and the synchronous demodulation of field programmable gate array chip realization sinewave modulation signal, system accuracy can be realized high precision by iterations in the algorithm and data word length decision;

2) invent at the scene in the programmable gate array chip amplitude, phase place and frequency that can online flexible configuration modulation signal;

3) the present invention realizes generation, synchronous demodulation and the signal Processing of two-way modulation signal by the monolithic field programmable gate array chip, helps the stable and integrated of resonance type optical fiber gyro detection system;

4) this bright employing optical fiber circulator can be avoided the light wave return laser light device in the fiber annular resonant cavity, thereby the stability of laser instrument is exerted an influence.

Description of drawings

Fig. 1 is based on the resonance type optical fiber gyro system and device structural drawing of coordinate rotation digital computer algorithm;

Fig. 2 is the principle schematic of coordinate rotation digital computer algorithm;

Fig. 3 is counterclockwise optical path signal modulation, demodulating system block diagram;

Fig. 4 is a signal sampling passage block diagram;

Fig. 5 is the feedback circuit block diagram of tuned laser output light frequency;

Fig. 6 is a gyro signal output channel block diagram;

Among the figure: laser instrument 1, feedback circuit 2, first coupling mechanism 3, first phase-modulator 4, first D/A 5, second digital to analog converter 6, second phase-modulator 7, the 3rd D/A 8, field programmable gate array chip 9, the 4th D/A 10, first A/D converter 11, second A/D converter 12, gyro signal output channel 13, the first signal sampling passage 14, secondary signal sampling channel 15, first optical fiber circulator 16, first photodetector 17, second photodetector 18, second optical fiber circulator 19, second coupling mechanism 20, fiber loop 21.

Embodiment

Shown in Figure 1, be connected with first coupling mechanism 3, first phase-modulator 4, first optical fiber circulator 16, second coupling mechanism 20, second optical fiber circulator 19, second phase-modulator 7, first coupling mechanism 3 based on the laser instrument 1 in the signal supervisory instrument of the resonance type optical fiber gyro of coordinate rotation digital computer algorithm; First phase-modulator 4 is connected with first D/A 5; Second phase-modulator 7 is connected with second D/A 6; First optical fiber circulator 16 is connected with first photodetector 17, the first signal sampling passage 14, first A/D converter 11; Second optical fiber circulator 19 is connected with second photodetector 18, secondary signal sampling channel 15, second A/D converter 12; Second coupling mechanism 20 is connected with fiber loop 21; The 3rd D/A 8 is connected with feedback circuit 2, laser instrument 1; The 4th D/A 10 is connected with gyro signal output channel 13; Field programmable gate array chip 9 is connected with first D/A 5, second D/A 6, the 3rd D/A 8, the 4th D/A 10, first A/D converter 11, second A/D converter 12 respectively.

The laser that is sent by laser instrument 1 is divided into two bundles through 50% coupling mechanism 3, this two bundles laser passes through phase-modulator (Phase Modulator respectively, PM) 4 and 7 modulate, be coupled into fiber loop (Fiber ring resonator by fiber coupler 20 again, FRR), (Counter Clockwise is CCW) with clockwise (Clockwise counterclockwise in formation, CW) two resonance light beams are coupled to photodetector 18 and 17 by optical fiber circulator 19 and 16 respectively; Send into field programmable gate array chip 9 through signal sampling passage 15 backs by high speed A device 12 from the signal that photodetector 18 comes out, extract the resonance frequency deviation by the field programmable gate array chip demodulation, in order to control laser instrument output light frequency, thereby make laser frequency lock at CCW light path tuning-points; Send into field programmable gate array chip 9 through signal sampling passage 14 backs by high speed A device 11 from the signal that photodetector 17 comes out, by after the field programmable gate array chip demodulation through after high speed D/A 10 and the gyro signal output channel 13, provide gyro open loop angular velocity signal.

Based on the resonance type optical fiber gyro signal detecting method of coordinate rotation digital computer algorithm, comprise the production method of modulation signal and demodulation method two parts of modulation signal:

Fig. 2 has provided counterclockwise optical path signal modulation, demodulating system block diagram.Dotted line block representation fpga chip produces sinewave modulation signal, by driving phase-modulator light wave is carried out phase modulation (PM), carries out synchronous demodulation by the output signal to photodetector simultaneously.

The production method of modulation signal is: sine wave signal is produced by the phase/amplitude modular converter of a totalizer and a cordic algorithm.Under clock control, and a frequency control word in the field programmable gate array chip (Frequency Control Word, FCW) register controlled produces sinusoidal wave frequency; The frequency control register is as the input of a phase accumulator, and the phase value of phase accumulator output is as the input phase amount z of a phase/amplitude modular converter ₀, z ₀It is the phase mass that needs to calculate trigonometric function value; The input initial vector coordinate figure x of phase/amplitude modular converter ₀Be set to certain value, y ₀Be set to 0, at this moment the output x of phase/amplitude modular converter _NAnd y _NProvide input phase amount z respectively ₀The sine and cosine functions value, output x _NProduce the sine voltage signal as modulation signal by a D/A;

The demodulation method of modulation signal is: under clock control, and a phase control words in the field programmable gate array chip (Phase Control Word, PCW) register controlled modulation signal and by the phase differential between the restituted signal; The output of the phase accumulator in phase control register and the modulation signal production method is as two input signals of a totalizer, and the phase value of totalizer output is as the input phase amount z of a phase/amplitude modular converter ₀, z ₀It is the phase mass that needs to calculate trigonometric function value; By an A/D converter signal that contains the frequency modulating signal component is sampled, its sampled value is as the input initial vector coordinate figure x of phase/amplitude modular converter ₀, y ₀Be set to 0; The output x of phase/amplitude modular converter _N(Low Pass Filter LPF), provides sinusoidal wave amplitude demodulation signal value synchronously, obtains the voltage restituted signal through a D/A again by a low-pass filter.With the voltage restituted signal, (Feedback Circuit, FBC) tuned laser output light frequency makes laser frequency lock on the resonance frequency of CCW light path by feedback circuit.

Described phase/amplitude modular converter is: the process of phase/amplitude conversion is that the iteration by a series of sub-angle rotary manipulation realizes; The input parameter of phase/amplitude modular converter is phase mass z ₀, initial vector coordinate figure x ₀And y ₀With y ₀Be set to 0, when its sub-angle rotary manipulation iterations N is tending towards infinite, the output x of phase/amplitude modular converter _NAnd y _NBe tending towards x respectively ₀Sin (z ₀) and x ₀Cos (z ₀), z _NBe tending towards 0.Thereby realize the conversion of phase/amplitude.

The iteration of described a series of sub-angle rotary manipulation is:

Coordinate rotation digital computer algorithm has rotation and directed two kinds of patterns.The key concept of rotary mode is by a series of sub-angle rotation θ with the vector of unit length on the x axle _j(j is an integer) rotates on the predetermined angle.Sub-angle rotary manipulation through N time can obtain sine value sin θ and cosine value cos θ, and wherein θ is all sub-angle θ _jSum.

Figure 3 shows that the principle schematic of coordinate rotation digital computer algorithm, vectorial V _j(x _j, y _j) through sub-angle θ _jRotary manipulation obtains vectorial V _J+1(x _J+1, y _J+1), its relation can be expressed as:

$\left\{\begin{array}{c}{x}_{j+1}=(x_j-y_j\·\tan {\mathrm{\θ}}_j)\·\cos {\mathrm{\θ}}_j\\ y_{j+1}=(y_j+x_j\·\tan {\mathrm{\θ}}_j)\·\cos {\mathrm{\θ}}_j\end{array}\right.---\left(1\right)$

In order to be easy in FPGA by the computing that simply adds/subtract, shift operation realizes following formula gyrator angle θ _jBe made as:

$\left\{\begin{array}{c}{\mathrm{\θ}}_j={\mathrm{\δ}}_j\·\arctan \left(2^{-j}\right)\\ K_j=\cos {\mathrm{\θ}}_j=\sqrt{\frac{1}{1+2^{-2j}}}\end{array}\right.---\left(2\right)$

Wherein, δ _jGet+1 or-1.Through the rotation of N second son angle, correction factor K is defined as:

$K=\underset{j=0}{\overset{N-1}{\mathrm{\Π}}}{K}_i=\underset{j=0}{\overset{N-1}{\mathrm{\Π}}}\sqrt{\frac{1}{1+2^{-2j}}}---\left(3\right)$

Is V by K with initial vector of unit length precorrection ₀(K, 0) can avoid the amplitude amplification factor cos θ in each sub-angle rotary manipulation in (1) formula _jTherefore the sub-angle rotary manipulation of cordic algorithm is expressed as:

$\left\{\begin{array}{c}{x}_{j+1}=x_j-{\mathrm{\δ}}_j\·y_j\·2^{-j}\\ y_{j+1}=y_j+{\mathrm{\δ}}_j\·x_j\·2^{-j}\\ z_{j+1}{=z}_j-{\mathrm{\δ}}_j\·\arctan \left(2^{-j}\right)\end{array}\right.---\left(4\right)$

Wherein, x ₀=K, y ₀=0, z ₀Be the predetermined angle θ that will calculate sine value and cosine value, work as z _j＞0 or z _j＜0 o'clock, δ _jBe taken as respectively+1 and-1.When group angle rotary manipulation times N is infinitely great, x _NAnd y _NEqual cos (θ) and sin (θ) respectively, thereby realized the conversion of phase/amplitude.According to (2) formula, the maximal value of sub-anglec of rotation sum can be expressed as:

For the scope Φ that makes the cordic algorithm angle calculation covers ± 180 °, can increase by the sub-angle rotary manipulation of twice j=0.Revised cordic algorithm phase/amplitude conversion operations can be described as:

(6)

$\left\{\begin{array}{cc}\begin{array}{c}{x}_{j+1}=x_j-{\mathrm{\δ}}_j\·y_j\·2^{-j+2}\\ y_{j+1}=y_j+{\mathrm{\δ}}_j\·x_j\·2^{-j+2}\\ z_{j+1}=z_j-{\mathrm{\δ}}_j\·\arctan \left(2^{-j+2}\right)\end{array}& j>2\end{array}\right.$

Because increased by the sub-angle rotary manipulation of twice j=0, N is the total degree of iterative operation, correction factor K is modified to:

$K={K_0}^2\·\underset{j=0}{\overset{N-3}{\mathrm{\Π}}}{K}_j=\frac{1}{2}\·\underset{j=0}{\overset{N-3}{\mathrm{\Π}}}\sqrt{\frac{1}{1+2^{-2j}}}---\left(7\right)$

Therefore, the x in (6) formula _j, y _jAnd z _jAs the input variable of sub-angle rotary manipulation, x _J+1, y _J+1And z _J+1Be the output variable of sub-angle rotary manipulation, (6) formula at the scene in the programmable gate array chip by add/subtract, shift operation realizes; x ₀=K, y ₀=0, z ₀Input be the angle value that will calculate trigonometric function value; The order of a series of sub-angle rotary manipulation iteration is j=0,1,2, and 3.......

If total iterations is N, the error based on the phase/amplitude modular converter of cordic algorithm that (6) formula is described can be expressed as:

$\left\{\begin{array}{c}{\cos z}_0-x_N\≤2^{-(N-3)}\\ {\sin z}_0-y_N\≤2^{-(N-3)}\end{array}\right.---\left(8\right)$

By (8) formula as can be seen, the precision of algorithm is by the decision of the figure place of the data register in iterations and the arithmetic operation, and precision that therefore can online adjustment algorithm can reach very high precision.

Shown in Figure 4, the circuit of described signal sampling passage is: the positive input terminal of first operational amplifier 1 is as signal input part, the negative input end of first operational amplifier 1 is connected with the output terminal of first operational amplifier 1, the output terminal of first operational amplifier 1 and first capacitor C ₁An end be connected; First capacitor C ₁The other end and first resistance R ₁, second resistance R ₂An end be connected first resistance R ₁Other end ground connection; The positive input terminal of second operational amplifier and second resistance R ₂The other end be connected the negative input end of second operational amplifier and the 3rd resistance R ₃, the 4th resistance R ₄An end be connected the output terminal of second operational amplifier and the 4th resistance R ₄The other end, second capacitor C ₂An end be connected the 3rd resistance R ₃Other end ground connection; Second capacitor C ₂The other end and the 5th resistance R ₅An end, the 3rd capacitor C ₃An end be connected the 3rd capacitor C ₃The other end and the 6th resistance R ₆An end, the positive input terminal of the 3rd operational amplifier be connected the 6th resistance R ₆Other end ground connection; The negative input end of the 3rd operational amplifier and the 7th resistance R ₇An end, the 8th resistance R ₈An end be connected the output terminal of the 3rd operational amplifier and the 5th resistance R ₅The other end, the 8th resistance R ₈The other end, the 9th resistance R ₉An end be connected the 7th resistance R ₇Other end ground connection; The 9th resistance R ₉The other end and the tenth resistance R ₁₀An end, the 4th capacitor C ₄An end be connected; The positive input terminal of four-operational amplifier and the tenth resistance R ₁₀The other end, the 5th capacitor C ₅An end be connected the negative input end of four-operational amplifier and the 11 resistance R ₁₁An end, the 12 resistance R ₁₂An end be connected the output terminal of four-operational amplifier and the 4th capacitor C ₄The other end, the 12 resistance R ₁₂The other end be connected the 11 resistance R ₁₁The other end, the 5th capacitor C ₅Other end ground connection.

The signal sampling passage is connected and forms with voltage follower, RC Hi-pass filter, amplifier, bandpass filter, A/D converter by photodetector.The signal sampling passage carries out filtering and pre-processing and amplifying to the output signal of photodetector.Because detected weak output signal, and noise is relatively large, therefore require the prime amplifier of signalling channel to possess low noise, high-gain and big dynamic range, the output impedance that need satisfy simultaneously with photodetector is complementary, has higher common-mode rejection ratio, to reach best squelch performance.

Fig. 4 is a signal sampling passage block diagram.Bandpass filter (Band Pass Filter, BFP), by low-pass filter (Low Pass Filter, LPF) and Hi-pass filter (High Pass Filter HPF) combines, to being carried out frequency-selecting by restituted signal.LPF and HPF all adopt active second order structure, and photodetector links to each other with a follower and carries out impedance matching.Follower is made up of first operational amplifier; First capacitor C ₁With first resistance R ₁Form partiting dc circuit; Amplifying circuit is by second operational amplifier and second resistance R ₂, the 3rd resistance R ₃, the 4th resistance R ₄Form; Hi-pass filter is by the 3rd operational amplifier and second capacitor C ₂, the 3rd capacitor C ₃, the 5th resistance R ₅, the 6th resistance R ₆, the 7th resistance R ₇, the 8th resistance R ₈Form; Low-pass filter is by four-operational amplifier and the 4th capacitor C ₄, the 5th capacitor C ₅, the 9th resistance R ₉, the tenth resistance R ₁₀, the 11 resistance R ₁₁, the 12 resistance R ₁₂Form.

The control signal passage of tuned laser output light frequency is joined by D/A, feedback circuit, laser instrument and forms.

Figure 5 shows that the circuit block diagram of described feedback circuit 2: the 13 resistance R ₁₃An end as input end, the 13 resistance R ₁₃The other end and the 6th capacitor C ₆An end, the 14 resistance R ₁₄An end be connected; The positive input terminal of the 5th operational amplifier and the 14 resistance R ₁₄The other end, the 7th capacitor C ₇An end be connected the negative input end of the 5th operational amplifier and the 15 resistance R ₁₅An end, the 16 resistance R ₁₆An end be connected the output terminal of the 5th operational amplifier and the 6th capacitor C ₆The other end, the 16 resistance R ₁₆The other end, the 17 resistance R ₁₇An end be connected the 15 resistance R ₁₅The other end, the 7th capacitor C ₇Other end ground connection; The positive input terminal of the 6th operational amplifier and the 18 resistance R ₁₈An end be connected the negative input end of the 6th operational amplifier and the 17 resistance R ₁₇The other end, the 19 resistance R ₁₉An end be connected the output terminal of the 6th operational amplifier and the 19 resistance R ₁₉The other end, the 22 resistance R ₂₂An end be connected the 18 resistance R ₁₈Other end ground connection; The positive input terminal of the 7th operational amplifier and the 21 resistance R ₂₁An end be connected the negative input end of the 7th operational amplifier and the 22 resistance R ₂₂The other end, the 23 resistance R ₂₃An end, the 25 resistance R ₂₅An end be connected the output terminal of the 7th operational amplifier and the 25 resistance R ₂₅The other end be connected the 21 resistance R ₂₁Other end ground connection; The 23 resistance R ₂₃The other end and the 20 resistance R ₂₀An end, the 24 resistance R ₂₄An end be connected the 20 resistance R ₂₀The other end be connected the 24 resistance R with power supply ₂₄Other end ground connection.

Feedback circuit is made up of low-pass filter, inverting amplifier, anti-phase totalizer.Because the tuning end of laser frequency can not add negative voltage, therefore need totalizer as level shift circuit.Low-pass filter is by the 5th operational amplifier and the 13 resistance R ₁₃, the 14 resistance R ₁₄, the 15 resistance R ₁₅, the 16 resistance R ₁₆, the 6th capacitor C ₆, the 7th capacitor C ₇Form; Inverting amplifier is by the 6th operational amplifier and the 17 resistance R ₁₇, the 18 resistance R ₁₈, the 19 resistance R ₁₉Form; The 20 resistance R ₂₀, the 24 resistance R ₂₄A direct current translation level is provided; Anti-phase totalizer is by the 7th operational amplifier and the 21 resistance R ₂₁, the 22 resistance R ₂₂, the 23 resistance R ₂₃, the 25 resistance R ₂₅Form.

The signal demodulation value that FPGA calculates, by D/A, low-pass filter output, this signal is the gyro turn signal.

Figure 6 shows that the circuit block diagram of described gyro signal output channel 13: the 26 resistance R ₂₆An end as input end, the 26 resistance R ₂₆The other end and the 8th capacitor C ₈An end, the 27 resistance R ₂₇An end be connected; The positive input terminal of the 8th operational amplifier and the 27 resistance R ₂₇The other end, the 9th capacitor C ₉An end be connected the negative input end of the 8th operational amplifier and the 28 resistance R ₂₈An end, the 29 resistance R ₂₉An end be connected the output terminal of the 8th operational amplifier and the 8th capacitor C ₈The other end, the 29 resistance R ₂₉The other end be connected the 9th capacitor C ₉The other end, the 28 resistance R ₂₈Other end ground connection.

Low-pass filter adopts active second-order low-pass filter, by the 8th operational amplifier and the 26 resistance R ₂₆, the 27 resistance R ₂₇, the 28 resistance R ₂₈, the 29 resistance R ₂₉, the 8th capacitor C ₈, the 9th capacitor C ₉Form.

Claims (4)

1. signal supervisory instrument based on the resonance type optical fiber gyro of coordinate rotation digital computer algorithm, it is characterized in that: laser instrument (1) is connected with first coupling mechanism (3), first phase-modulator (4), first optical fiber circulator (16), second coupling mechanism (20), second optical fiber circulator (19), second phase-modulator (7), first coupling mechanism (3); First phase-modulator (4) is connected with first D/A (5); Second phase-modulator (7) is connected with second D/A (6); First optical fiber circulator (16) is connected with first photodetector (17), the first signal sampling passage (14), first A/D converter (11); Second optical fiber circulator (19) is connected with second photodetector (18), secondary signal sampling channel (15), second A/D converter (12); Second coupling mechanism (20) is connected with fiber loop (21); The 3rd D/A (8) is connected with feedback circuit (2), laser instrument (1); The 4th D/A (10) is connected with gyro signal output channel (13); Field programmable gate array chip (9) is connected with first D/A (5), second D/A (6), the 3rd D/A (8), the 4th D/A (10), first A/D converter (11), second A/D converter (12) respectively.

2. a kind of resonance type optical fiber gyro signal detecting device according to claim 1 based on coordinate rotation digital computer algorithm, the circuit that it is characterized in that described first, second signal sampling passage is: the positive input terminal of first operational amplifier is as signal input part, the negative input end of first operational amplifier is connected with the output terminal of first operational amplifier, the output terminal of first operational amplifier and the first electric capacity (C ₁) an end be connected; First electric capacity (the C ₁) the other end and the first resistance (R ₁), the second resistance (R ₂) an end be connected the first resistance (R ₁) other end ground connection; The positive input terminal of second operational amplifier and the second resistance (R ₂) the other end be connected the negative input end of second operational amplifier and the 3rd resistance (R ₃), the 4th resistance (R ₄) an end be connected the output terminal of second operational amplifier and the 4th resistance (R ₄The other end, the second electric capacity (C ₂An end be connected the 3rd resistance (R ₃Other end ground connection; Second electric capacity (the C ₂The other end and the 5th resistance (R ₅) an end, the 3rd electric capacity (C ₃) an end be connected the 3rd electric capacity (C ₃) the other end and the 6th resistance (R ₆) an end, the positive input terminal of the 3rd operational amplifier be connected the 6th resistance (R ₆) other end ground connection; The negative input end of the 3rd operational amplifier and the 7th resistance (R ₇) an end, the 8th resistance (R ₈) an end be connected the output terminal of the 3rd operational amplifier and the 5th resistance (R ₅) the other end, the 8th resistance (R ₈) the other end, the 9th resistance (R ₉) an end be connected the 7th resistance (R ₇) other end ground connection; The 9th resistance (R ₉) the other end and the tenth resistance (R ₁₀) an end, the 4th electric capacity (C ₄) an end be connected; The positive input terminal of four-operational amplifier and the tenth resistance (R ₁₀) the other end, the 5th electric capacity (C ₅) an end be connected the negative input end of four-operational amplifier and the 11 resistance (R ₁₁) an end, the 12 resistance (R ₁₂) an end be connected the output terminal of four-operational amplifier and the 4th electric capacity (C ₄) the other end, the 12 resistance (R ₁₂) the other end be connected the 11 resistance (R ₁₁) the other end, the 5th electric capacity (C ₅) other end ground connection.

3. a kind of resonance type optical fiber gyro signal detecting device based on coordinate rotation digital computer algorithm according to claim 1 is characterized in that the circuit of described feedback circuit (2) is: the 13 resistance (R ₁₃) an end as input end, the 13 resistance (R ₁₃) the other end and the 6th electric capacity (C ₆) an end, the 14 resistance (R ₁₄) an end be connected; The positive input terminal of the 5th operational amplifier and the 14 resistance (R ₁₄) the other end, the 7th electric capacity (C ₇) an end be connected the negative input end of the 5th operational amplifier and the 15 resistance (R ₁₅) an end, the 16 resistance (R ₁₆) an end be connected the output terminal of the 5th operational amplifier and the 6th electric capacity (C ₆) the other end, the 16 resistance (R ₁₆) the other end, the 17 resistance (R ₁₇) an end be connected the 15 resistance (R ₁₅) the other end, the 7th electric capacity (C ₇) other end ground connection; The positive input terminal of the 6th operational amplifier and the 18 resistance (R ₁₈) an end be connected the negative input end of the 6th operational amplifier and the 17 resistance (R ₁₇) the other end, the 19 resistance (R ₁₉) an end be connected the output terminal of the 6th operational amplifier and the 19 resistance (R ₁₉) the other end, the 22 resistance (R ₂₂) an end be connected the 18 resistance (R ₁₈) other end ground connection; The positive input terminal of the 7th operational amplifier and the 21 resistance (R ₂₁) an end be connected the negative input end of the 7th operational amplifier and the 22 resistance (R ₂₂) the other end, the 23 resistance (R ₂₃) an end, the 25 resistance (R ₂₅) an end be connected the output terminal of the 7th operational amplifier and the 25 resistance (R ₂₅) the other end be connected the 21 resistance (R ₂₁) other end ground connection; The 23 resistance (R ₂₃) the other end and the 20 resistance (R ₂₀) an end, the 24 resistance (R ₂₄) an end be connected the 20 resistance (R ₂₀) the other end be connected the 24 resistance (R with power supply ₂₄Other end ground connection.

4. a kind of resonance type optical fiber gyro signal detecting device based on coordinate rotation digital computer algorithm according to claim 1 is characterized in that the circuit of described gyro signal output channel (13) is: the 26 resistance (R ₂₆) an end as input end, the 26 resistance (R ₂₆) the other end and the 8th electric capacity (C ₈) an end, the 27 resistance (R ₂₇) an end be connected; The positive input terminal of the 8th operational amplifier and the 27 resistance (R ₂₇) the other end, the 9th electric capacity (C ₉) an end be connected the negative input end of the 8th operational amplifier and the 28 resistance (R ₂₈) an end, the 29 resistance (R ₂₉) an end be connected the output terminal of the 8th operational amplifier and the 8th electric capacity (C ₈) the other end, the 29 resistance (R ₂₉) the other end be connected the 9th electric capacity (C ₉) the other end, the 28 resistance (R ₂₈) other end ground connection.

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