CN115876181A - Digital-analog hybrid integrated system of fiber-optic gyroscope - Google Patents
Digital-analog hybrid integrated system of fiber-optic gyroscope Download PDFInfo
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- CN115876181A CN115876181A CN202211737702.9A CN202211737702A CN115876181A CN 115876181 A CN115876181 A CN 115876181A CN 202211737702 A CN202211737702 A CN 202211737702A CN 115876181 A CN115876181 A CN 115876181A
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Abstract
The invention discloses a digital-analog hybrid integration system of a fiber-optic gyroscope, which comprises a digital-analog hybrid integration module and a digital closed-loop fiber-optic gyroscope module, wherein the digital-analog hybrid integration module comprises an FPGA module, a PROM module, an AD module and a DA module, and the PROM module, the AD module and the DA module are electrically connected with the FPGA module. The invention forms a digital-analog hybrid integrated chip by relying on the mature FPGA module BQ2V1000, the PROM module BQ18V04, the 12-bit AD module B9235 and the 14-bit DA module B9764 and through a system-level packaging technology, and provides a miniaturization scheme for the optical fiber gyro signal processing circuit, the integrated chip adopts BGA plastic package, the number of pins is 256, the packaging size is 18mm multiplied by 18mm, the area is reduced by 33% compared with the original discrete device, the integrated chip shows excellent performance no matter the chip-level test or the optical fiber gyro system-level test, and the system-level packaging technology has the advantages of flexible design, good process compatibility and low research and development cost, can improve the coupling efficiency, and improves the environmental adaptability and reliability.
Description
Technical Field
The invention belongs to the technical field of fiber optic gyroscopes, and particularly relates to a digital-analog hybrid integrated system of a fiber optic gyroscope.
Background
The optical fiber gyroscope is an optical fiber angular velocity sensor, which is one of various optical fiber sensors with the most promising popularization and application. The fiber optic gyroscope has the same advantages as the annular laser gyroscope in that no mechanical moving part, no preheating time, insensitive acceleration, wide dynamic range, digital output, small size and the like, and in addition, the fiber optic gyroscope also overcomes the fatal defects of high cost, locking phenomenon and the like of the annular laser gyroscope;
with the development of the photoelectric technology, the integration of photoelectric hybrid integration, analog and digital circuits and the like in the fiber-optic gyroscope has become a development trend, and is also a key for the fiber-optic gyroscope to enter into practicality and batch production, the fiber-optic gyroscope needs to be produced in batch, and the detection circuit of the fiber-optic gyroscope is inevitably required to have the characteristics of high reliability, good consistency, easy integration and flexible application.
Disclosure of Invention
The invention aims to provide a digital-analog hybrid integrated system of a fiber-optic gyroscope, which aims to solve the problems that in the prior art, the size, the weight and the power consumption of a circuit are high, and each discrete component needs to be coupled with an optical fiber, so that the optical fiber has multiple fusion points, multiple and complex processes, low coupling efficiency, high possibility of failure, poor environmental adaptability and poor reliability.
In order to achieve the purpose, the invention adopts the following technical scheme:
a digital-analog hybrid integration system of a fiber-optic gyroscope comprises a digital-analog hybrid integration module and a digital closed-loop fiber-optic gyroscope module, wherein the digital-analog hybrid integration module comprises an FPGA module, a PROM module, an AD module and a DA module, and the PROM module, the AD module and the DA module are electrically connected with the FPGA module;
the digital closed-loop fiber optic gyroscope module comprises a detector, a wide-spectrum light source, a pre-amplification circuit module, an integrated digital circuit module, a driving circuit module, a coupler, a Y waveguide module and a fiber ring, wherein the wide-spectrum light source and the detector are connected with the coupler, the coupler is connected with the Y waveguide module, the Y waveguide module is connected with the fiber ring, the detector is further connected with the pre-amplification circuit module, the pre-amplification circuit module is connected with an AD module, the AD module is further connected with the integrated digital circuit module, the integrated digital circuit module is connected with a DA module, the DA module is further connected with the driving circuit module, and the driving circuit module is connected with the Y waveguide module.
Preferably, the model number of the AD module is B9235 and is used for inputting signals, the model number of the DA module is B9764 and is used for outputting signals, the model number of the FPGA module is BQ2V1000 and is used for connecting peripheral devices, and the model number of the PROM module is BQ18V04 and is used for controlling program downloading.
Preferably, the digital-analog hybrid integrated module is used for receiving analog signals, completing analog-to-digital conversion in the circuit, receiving digital signals, completing digital-to-analog conversion in the circuit, providing functions of gyroscope data acquisition, digital signal processing and the like, and realizing data interaction with peripheral devices or interfaces of the circuit through a large number of general I/Os.
Preferably, the wide-spectrum light source is used for providing a reference spectrum for the whole light path, the detector is used for converting output optical power of the interferometer into voltage, the coupler is used for connecting the wide-spectrum light source, the detector and the sensitive loop to realize the minimum reciprocity structure of the fiber-optic gyroscope, and the Y waveguide module is used for improving the detection sensitivity of the rotating speed signal and distinguishing the rotating speed direction.
Preferably, the digital-analog hybrid integrated module is connected to the module voltage to normally work, the FPGA code stream is programmed to connect the digital signal output end of the AD module with the digital signal input end of the DA module, the PROM module is downloaded and burned, analog signals are input from the VINA _ a and VINB _ a differential analog signal input ends of the AD module, signals of the IOUTA _ D and IOUTB _ D differential analog signal output ends of the DA module are obtained, and the hybrid integrated chip can be integrally verified.
Preferably, the FPGA module is connected to the module power supply, all other power supplies are disconnected, the test code stream is used for configuring the FPGA to be tested, then test excitation is applied, response is analyzed, the AD module, the DA module and the PROM module are respectively connected to the module power supply, all other power supplies are respectively disconnected, and the test of the AD module, the DA module and the PROM module is completed.
Preferably, the FPGA module, the PROM module, the AD module and the DA module form a digital-analog hybrid integrated chip through a system-in-package technology, and a miniaturization scheme is provided for the digital closed-loop fiber-optic gyroscope module, wherein the digital-analog hybrid integrated chip is plastically packaged by BGA, the number of pins is 256, the packaging size is 18mm multiplied by 18mm, and the area is reduced by 33% compared with that of an original discrete device.
Preferably, the voltage on the Y waveguide module is the sum of the modulation voltage and the feedback voltage, and is used for enabling the reset voltage to realize rapid 2 pi tracking.
The invention has the technical effects and advantages that: compared with the prior art, the digital-analog hybrid integrated system of the fiber-optic gyroscope provided by the invention has the following advantages:
the invention forms a digital-analog hybrid integrated chip by relying on the mature FPGA module BQ2V1000, the PROM module BQ18V04, the 12-bit AD module B9235 and the 14-bit DA module B9764 and through a system-level packaging technology, and provides a miniaturization scheme for the optical fiber gyro signal processing circuit, the integrated chip adopts BGA plastic package, the number of pins is 256, the packaging size is 18mm multiplied by 18mm, the area is reduced by 33% compared with the original discrete device, the integrated chip shows excellent performance no matter the chip-level test or the optical fiber gyro system-level test, and the system-level packaging technology has the advantages of flexible design, good process compatibility and low research and development cost, can improve the coupling efficiency, and improves the environmental adaptability and reliability.
Drawings
Fig. 1 is a block diagram of a digital-analog hybrid integrated system of a fiber-optic gyroscope according to the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. The specific embodiments described herein are merely illustrative of the invention and do not delimit the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The invention provides a digital-analog hybrid integration system of a fiber-optic gyroscope, which comprises a digital-analog hybrid integration module and a digital closed-loop fiber-optic gyroscope module, wherein the digital-analog hybrid integration module comprises an FPGA module, a PROM module, an AD module and a DA module, and the PROM module, the AD module and the DA module are electrically connected with the FPGA module.
Additionally, a hybrid integrated circuit is included, the circuit comprising: the device comprises an analog-digital conversion and pre-stage conditioning unit, a digital-analog conversion and post-stage driving unit, a programmable logic and configuration memory unit, a serial digital-analog conversion unit, a serial communication unit and an input gating unit; each unit is electrically connected through the substrate, and each unit works cooperatively to realize the signal processing of the fiber-optic gyroscope.
The analog-to-digital conversion and pre-stage conditioning unit comprises a high-speed differential operational amplifier and a high-speed analog-to-digital converter, the high-speed differential operational amplifier is connected with the high-speed analog-to-digital converter, the high-speed differential operational amplifier amplifies the acquired signal of the fiber-optic gyroscope detector, and the amplified signal is input into the high-speed analog-to-digital converter for digital-to-analog conversion to obtain a 14-bit digital signal.
The digital-to-analog conversion and rear-stage driving unit comprises a high-speed digital-to-analog converter and a rail-to-rail operational amplifier; the output end of the high-speed digital-to-analog converter is connected with the input end of the rail-to-rail operational amplifier; the digital-to-analog conversion and post-stage driving unit converts the 16-bit digital signal into a differential analog signal, and the converted analog signal is used for driving the y waveguide. 6. Preferably, the programmable logic and configuration memory unit comprises a programmable logic array and a flash memory chip; the programmable logic array is used for processing digital signals output by the analog-to-digital conversion and pre-stage conditioning unit, and the flash memory chip is used for storing programs and data in the programmable logic array. The serial digital-to-analog conversion unit is a 12-bit spi serial digital-to-analog converter. The serial port communication unit comprises a 1-path rs-485/422 interface receiving unit and a 1-path rs-485/422 interface sending unit and is used for data communication.
The digital closed-loop fiber optic gyroscope module comprises a detector, a wide-spectrum light source, a pre-amplification circuit module, an integrated digital circuit module, a driving circuit module, a coupler, a Y waveguide module and a fiber ring, wherein the wide-spectrum light source and the detector are connected with the coupler, the coupler is connected with the Y waveguide module, the Y waveguide module is connected with the fiber ring, the detector is further connected with the pre-amplification circuit module, the pre-amplification circuit module is connected with an AD module, the AD module is further connected with the integrated digital circuit module, the integrated digital circuit module is connected with a DA module, the DA module is further connected with the driving circuit module, and the driving circuit module is connected with the Y waveguide module.
As an optimization scheme of the invention, the model of the AD module is B9235 for inputting signals, the model of the DA module is B9764 for outputting signals, the model of the FPGA module is BQ2V1000 for connecting peripheral devices, the model of the PROM module is BQ18V04 for controlling program downloading and integrating the digital closed-loop fiber optic gyro module, and the integrated design is performed by combining the universality of the integrated chip and the process, size and cost of the integrated design according to the application characteristics of weak signal detection of the fiber optic gyro, and the occupied area of the 4 chips is almost one third of the whole circuit board, as shown in table 1, so that the AD module, the DA module, the FPGA module and the PROM module are integrated, the size of the circuit board can be reduced, the design difficulty of the circuit board is reduced, and the AD module, the DA module, the FPGA module and the PROM module are all imported industrial-grade devices, and the localization rate of electronic components of the fiber optic gyro detection circuit can be effectively improved, and the reliability of the circuit system is improved;
| device with a metal layer | AD | DA | FPGA | PROM | Total of |
| Size (mm) 2 ) | 9.7*8.4 | 10*9.8 | 17*17 | 6.5*6.8 | 482 |
TABLE 1
As an optimization scheme of the invention, the digital-analog hybrid integrated module is used for receiving analog signals, completing analog-digital conversion in a circuit, receiving digital signals, completing digital-analog conversion in the circuit, providing functions of gyroscope data acquisition, digital signal processing and the like, realizing data interaction with peripheral devices or interfaces of the circuit through a large number of general I/Os, facing a 3.3V application platform, having an internal signal connection line completely the same as that of a fiber-optic gyroscope digital closed-loop detection circuit, and realizing functions of general FPGA logic and the like;
as an optimized scheme of the invention, a wide-spectrum light source is used for providing a reference spectrum for a whole light path, a detector is used for converting the output light power of an interferometer into voltage, a coupler is used for connecting the wide-spectrum light source, the detector and a sensitive loop to realize the minimum reciprocity structure of the fiber-optic gyroscope, and a Y waveguide module is used for improving the detection sensitivity of a rotating speed signal and distinguishing rotating speed directions;
in the optical fiber gyroscope, in order to improve the detection sensitivity of a rotating speed signal and distinguish the rotating speed direction, the electro-optical modulation effect of a Y waveguide module is utilized, phase difference in the form of square waves is artificially added into the phase difference of two interference lights, and the time for the light to propagate in an optical fiber ring for one circle is set as the transition time tau loop The voltage applied to the Y-waveguide module is a voltage having a period of 2 tau loop The square wave form of (1). ByThe two main lights in the sensitive ring have the same modulating voltage and have the time difference tau loop With a period of 2 tau loop The modulated voltage square wave can make two main lights respectively produce the same phase phi and opposite phase phi (the phase difference is 180 DEG) with the square wave voltage m1 And phi m2 The phase difference between two beams of light generated by the modulated square wave is delta phi m The difference between the modulation phases of the two beams is in the form of square wave with the same shape as the modulation square wave, and the phase difference between the two beams of interference light is Sagnac phase difference delta phi which is proportional to the rotation speed s Modulating phase difference delta phi with square wave m Sum, square wave modulation phase difference Δ φ m Amplitude phi of m Generally referred to as modulation depth, and needs to be selected according to the precision level of the fiber-optic gyroscope, the application environment, the performance of the optical device, and the like.
The digital-analog hybrid integrated module is used for integrated packaging of various chips, and external test points are reserved for all internal interconnections, so that the system visibility and the performance control performance are improved. All four modules can be subjected to divide-and-conquer testing, when a certain module needs to be tested, the module can be tested independently only by electrifying the module and powering off the other three modules, and the testing method is as follows;
s1, a digital-analog hybrid integrated module is connected to a module voltage to normally work, an FPGA code stream is compiled to enable a digital signal output end of an AD module to be connected with a digital signal input end of a DA module, a PROM module is downloaded and burnt, analog signals are input from a VINA _ A and VINB _ A differential analog signal input ends of the AD module, signals of an IOUTA _ D and IOUTB _ D differential analog signal output ends of the DA module are obtained, and then the hybrid integrated chip can be integrally verified;
s2, the FPGA module is connected with the power supply of the module, all other power supplies are disconnected, test excitation is applied after the FPGA to be tested is configured by using a test code stream, response is analyzed, the AD module, the DA module and the PROM module are respectively connected with the power supply of the module, all other power supplies are respectively disconnected, and the test of the AD module, the DA module and the PROM module is completed;
as an optimization scheme of the invention, the FPGA module, the PROM module, the AD module and the DA module form a digital-analog hybrid integrated chip through a system-level packaging technology, and a miniaturization scheme is provided for the digital closed-loop fiber-optic gyroscope module, the digital-analog hybrid integrated chip adopts BGA plastic packaging, the number of pins is 256, the packaging size is 18mm multiplied by 18mm, and the area is reduced by 33% compared with the area of an original discrete device;
as an optimized scheme of the invention, the voltage on the Y waveguide module is the sum of the modulation voltage and the feedback voltage and is used for realizing the rapid 2 pi tracking of the reset voltage, and the Y waveguide module is added with a step height delta phi f (real-time tracking of. Delta. Phi.) s And is equal to delta phi s Equal reversal) with a step duration of τ loop The step wave voltage signal makes the phase difference generated between the two beams of light be delta phi f (except when reset). The phase difference delta phi between the two beams is not considered when the square wave modulation phase difference is not considered f +Δφ s Approximately equals to zero, closed-loop work is realized, and the step wave voltage signal can not be continuously increased, so that the step wave can generate delta phi at the reset moment f A greatly different reset phase difference. When the phase difference is reset and delta phi f Exactly by 2 pi (delta phi) r-e When =0, Δ φ r-e Reset error), no error will occur at the reset position due to the periodicity of the raised cosine interference function, and in order to ensure that the height of the step wave reset corresponds to an accurate 2 pi, a closed-loop control of 2 pi voltage is added on the basis of a rotating speed closed loop, which is also called as a second closed-loop control.
Finally, it should be noted that: although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that modifications may be made to the embodiments or portions thereof without departing from the spirit and scope of the invention.
Claims (8)
1. The utility model provides a mixed integrated system of optic fibre top digital analog, includes mixed integrated module of digital analog and digital closed loop optic fibre top module, its characterized in that: the digital-analog hybrid integrated module comprises an FPGA module, a PROM module, an AD module and a DA module, and the PROM module, the AD module and the DA module are electrically connected with the FPGA module;
the digital-analog hybrid integrated module is used for receiving analog signals, completing analog-digital conversion in the circuit, receiving digital signals, completing digital-analog conversion in the circuit, providing functions of gyroscope data acquisition, digital signal processing and the like, and realizing data interaction with peripheral devices or interfaces of the circuit through a large number of general I/O.
2. The fiber-optic gyroscope digital-analog hybrid integrated system according to claim 1, characterized in that: the model number of the AD module is B9235 and is used for inputting signals, the model number of the DA module is B9764 and is used for outputting signals, the model number of the FPGA module is BQ2V1000 and is used for connecting peripheral devices, and the model number of the PROM module is BQ18V04 and is used for controlling program downloading.
3. The digital-analog hybrid integrated system of the fiber-optic gyroscope of claim 3, wherein: the digital closed-loop fiber optic gyroscope module comprises a detector, a wide-spectrum light source, a pre-amplification circuit module, an integrated digital circuit module, a driving circuit module, a coupler, a Y waveguide module and a fiber ring, wherein the wide-spectrum light source and the detector are connected with the coupler, the coupler is connected with the Y waveguide module, the Y waveguide module is connected with the fiber ring, the detector is further connected with the pre-amplification circuit module, the pre-amplification circuit module is connected with an AD module, the AD module is further connected with the integrated digital circuit module, the integrated digital circuit module is connected with a DA module, the DA module is further connected with the driving circuit module, and the driving circuit module is connected with the Y waveguide module.
4. The digital-analog hybrid integrated system of the fiber-optic gyroscope of claim 3, wherein: the wide-spectrum light source is used for providing a reference spectrum for the whole light path, the detector is used for converting the output light power of the interferometer into voltage, the coupler is used for connecting the wide-spectrum light source, the detector and the sensitive loop to realize the minimum reciprocal structure of the fiber-optic gyroscope, and the Y waveguide module is used for improving the detection sensitivity of the rotating speed signal and distinguishing the rotating speed direction.
5. The digital-analog hybrid integrated system of the fiber-optic gyroscope of claim 4, wherein: the digital-analog hybrid integrated module is connected with the module voltage to enable the module to work normally, the FPGA code stream is compiled to enable the digital signal output end of the AD module to be connected with the digital signal input end of the DA module, the PROM module is downloaded and burnt, analog signals are input from the VINA _ A and VINB _ A differential analog signal input ends of the AD module, signals of the IOUTA _ D and IOUTB _ D differential analog signal output ends of the DA module are obtained, and therefore the hybrid integrated chip can be subjected to overall verification.
6. The digital-analog hybrid integrated system of the fiber-optic gyroscope of claim 5, wherein: the FPGA module is connected with the power supply of the module, all other power supplies are disconnected, test excitation is applied after the FPGA to be tested is configured by using the test code stream, response is analyzed, the AD module, the DA module and the PROM module are respectively connected with the power supply of the module, all other power supplies are disconnected, and the test of the AD module, the DA module and the PROM module is completed.
7. The digital-analog hybrid integrated system of the fiber-optic gyroscope of claim 6, wherein: the FPGA module, the PROM module, the AD module and the DA module form a digital-analog hybrid integrated chip through a system-level packaging technology, a miniaturization scheme is provided for the digital closed-loop fiber-optic gyroscope module, the digital-analog hybrid integrated chip adopts BGA plastic package, the number of pins is 256, the packaging size is 18mm multiplied by 18mm, and the area is reduced by 33% compared with that of an original discrete device.
8. The digital-analog hybrid integrated system of the fiber-optic gyroscope of claim 7, wherein: and the voltage on the Y waveguide module is the sum of the modulation voltage and the feedback voltage and is used for enabling the reset voltage to realize rapid 2 pi tracking.
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| CN116046022A (en) * | 2023-03-30 | 2023-05-02 | 中国船舶集团有限公司第七〇七研究所 | Simulation test method and system of fiber-optic gyroscope |
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| CN116046022A (en) * | 2023-03-30 | 2023-05-02 | 中国船舶集团有限公司第七〇七研究所 | Simulation test method and system of fiber-optic gyroscope |
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