Standardized high-precision acquisition module for cold atom interferometer

Abstract

The invention relates to a standardized high-precision acquisition module for a cold atom interferometer, and the module is characterized in that a core processing module respectively drives a first analog-to-digital converter, a second analog-to-digital converter and a third analog-to-digital converter to acquire an atomic fluorescence signal, a laser power signal and a vibration signal generated by the interference of the cold atom interferometer; the first analog-to-digital converter, the second analog-to-digital converter and the third analog-to-digital converter respectively convert analog signals of the atomic fluorescence signal, the laser power signal and the vibration signal into digital signals and then upload the digital signals to the core processing module; the device can be universally used for acquisition modules of cold atom interference type gyroscopes, cold atom interference type gravimeters and cold atom interference type gravity gradiometers, has the functions of acquiring fluorescence collection signals, power-stable optical signals and high-precision vibration signals, and can ensure higher acquisition precision and lower acquisition noise.

Description

Technical Field

[0001] The invention relates to the field of quantum precision measurement, and in particular to a standardized high-precision acquisition module for a cold atom interferometer. Background Art

[0002] Cold atom interferometer is a new type of quantum measurement instrument that has developed rapidly in the past two decades. This type of instrument can measure by manipulating atomic interference. It has gained increasing attention due to its high sensitivity and measurement accuracy, and has gradually developed from laboratory research to practical instruments. Cold atom interferometer has extremely high application prospects in inertial quantity measurement, gravity measurement, gravity gradient measurement and magnetic measurement, and plays a very important role in geological exploration, inertial navigation, geophysics and other fields.

[0003] Cold atom interferometers also have many functions that require the acquisition of analog signals, such as the high-bandwidth, low-noise acquisition of atomic fluorescence signals, the high-precision acquisition of vibration signals, and the acquisition of optical power signals. Currently, there are relatively mature commercial acquisition modules, which are mostly used by major universities and research institutes at home and abroad. However, this type of module is not designed for cold atom interferometers, and when used, it often faces the disadvantages of redundant functions, large size, non-universal interfaces, poor synchronization, and poor environmental adaptability. Summary of the invention

[0004] In view of the technical problems existing in the prior art, the present invention provides a standardized high-precision acquisition module for cold atom interferometers, which can be generally used as acquisition modules of cold atom interferometric gyroscopes, cold atom interferometric gravimeters and cold atom interferometric gravity gradiometers, and has the functions of collecting fluorescence collection signals, power-stabilized optical signals and high-precision vibration signals, while ensuring high acquisition accuracy and low acquisition noise, and the module needs to be universal and applicable to most cold atom interferometers.

[0005] According to a first aspect of the present invention, there is provided a standardized high-precision acquisition module for a cold atom interferometer, comprising: an atomic fluorescence acquisition module, an optical power acquisition module, a vibration acquisition module and a core processing module; The atomic fluorescence acquisition module includes: a first analog-to-digital converter for acquiring atomic fluorescence signals; the optical power acquisition module includes: a second analog-to-digital converter for acquiring laser power signals; the vibration acquisition module includes: a third analog-to-digital converter for acquiring vibration signals; The core processing module respectively drives the first analog-to-digital converter, the second analog-to-digital converter and the third analog-to-digital converter to collect the atomic fluorescence signal, laser power signal and vibration signal generated by the interference of the cold atom interferometer. The first analog-to-digital converter, the second analog-to-digital converter and the third analog-to-digital converter respectively convert the analog signals of the atomic fluorescence signal, laser power signal and vibration signal into digital signals and upload them to the core processing module.

[0006] Based on the above technical solution, the present invention can also make the following improvements.

[0007] Optionally, the atomic fluorescence acquisition module further includes: a photoelectric converter, a second-order low-pass filter module, an operational amplifier scaler, a differential operational amplifier and a reference source; The photoelectric converter collects the atomic fluorescence signal, and the output voltage analog signal is sequentially passed through the second-order low-pass filter module, the operational amplifier scaling and the differential operational amplifier, and the single-ended voltage analog signal is converted into a differential signal, and then the differential signal is input into the first analog-to-digital conversion chip to be converted into a digital signal and transmitted to the core processing module; the operational amplifier scaling and the differential operational amplifier are used to realize the two-level adjustable amplification gain of the atomic fluorescence acquisition module; The reference source is used to provide a reference voltage for the first analog-to-digital conversion chip.

[0008] Optionally, the first analog-to-digital conversion chip uses an analog-to-digital converter AD9266-20, and the reference source includes: a reference voltage source LM399 and an inverse proportional amplifier; The positive and negative input terminals of the reference voltage source LM399 are connected to positive and negative 12V voltages respectively, the positive output terminal is grounded, and the negative output terminal outputs a negative voltage, which then passes through the reverse proportional amplifier to generate the reference voltage of the first analog-to-digital conversion chip.

[0009] Optionally, the second analog-to-digital conversion chip in the optical power collection module uses an analog-to-digital converter AD9266-20, and the gain of the optical power collection module is fixed.

[0010] Optionally, the vibration collection module further includes: a linear regulator, a differential amplifier module, a proportional amplifier module and a filter module; The three linear regulators are used to respectively collect analog signals of vibration signals in the three-axis directions of XYZ. The analog signals of the vibration signals pass through the differential amplifier module, the proportional amplifier module and the filtering module in sequence, and are then collected by the third analog-to-digital converter and converted into digital signals for transmission to the core processing module.

[0011] Optionally, the third analog-to-digital converter adopts an analog-to-digital converter LTC2500-32; and the resistors used in the differential amplifier module and the proportional amplifier module are banks of the LT5400 series.

[0012] Optionally, the connector includes: a communication interface, an analog signal interface and a power input interface; The communication interface is used to provide an interface for external communication, and the analog signal interface is used to receive analog signals sent externally; the analog signals include: atomic fluorescence signals, laser power signals and vibration signals; the power input interface is used to receive external input power.

[0013] Optionally, the acquisition module further includes: a power supply module; the power supply module includes: an isolated power supply, a high-frequency DC / DC module, a linear regulator and a multi-channel DC / DC module; The isolated power supply outputs two power supplies; one power supply output by the isolated power supply is converted into positive and negative electricity by the high-frequency DC / DC module, and then the positive and negative electricity are converted by the linear regulator to power the analog end; the other power supply output by the isolated power supply is converted by the multi-channel DC / DC module to power the digital end; the power supply module also provides a separate line of isolated power supply for the vibration collection module.

[0014] Optionally, the core processing module includes: a main control chip; the main control chip is a FMQL10S400 SOC chip; The main control chip is used to drive the atomic fluorescence acquisition module, optical power acquisition module and vibration acquisition module to collect signals, and upload each signal to the host computer after digital filtering; the main control chip is also used to drive each interface to control the information interaction and timing synchronization between the acquisition module and the outside.

[0015] Optionally, each module of the acquisition module is arranged on a 6U standard board, and the standard board separates the analog area, the digital area and the high-precision acquisition area.

[0016] The invention provides a standardized high-precision acquisition module for a cold atom interferometer, which integrates all analog model acquisition functions required by a cold atom interferometer system on a 6U board and is applicable to all cold atom interferometer systems. The high-precision acquisition module adopts a completely isolated design, which completely isolates a digital part from a high-precision acquisition part on the same circuit board, effectively reducing crosstalk between circuits, improving the acquisition accuracy of vibration signals, and improving the accuracy of vibration compensation of the cold atom interferometer. Different acquisition systems use different filtering designs and power supply designs, which reduces acquisition noise to the greatest extent and simplifies the design of the power supply module. The acquisition of analog signals of all different types, bandwidths, bit numbers, and sampling rates uses the same core processor, which can improve the timing synchronization between different acquisition signals, simplify the interconnection lines between different acquisition modules, and unify the external communication interfaces of different acquisition modules. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 A structural block diagram of a standardized high-precision acquisition module for a cold atom interferometer provided by the present invention; Figure 2 A schematic diagram of reverse connection of a reference source provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0018] The principles and features of the present invention are described below in conjunction with the accompanying drawings. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0019] Figure 1 The structural block diagram of an embodiment of a standardized high-precision acquisition module for cold atom interferometer provided by the present invention is as follows: Figure 1 As shown, the acquisition module includes: an atomic fluorescence acquisition module, an optical power acquisition module, a vibration acquisition module and a core processing module.

[0020] The atomic fluorescence acquisition module includes: a first analog-to-digital converter for acquiring atomic fluorescence signals; the optical power acquisition module includes: a second analog-to-digital converter for acquiring laser power signals; the vibration acquisition module includes: a third analog-to-digital converter for acquiring vibration signals.

[0021] The core processing module drives the first analog-to-digital converter, the second analog-to-digital converter and the third analog-to-digital converter to collect the atomic fluorescence signal, laser power signal and vibration signal generated by the cold atom interferometer interference. The first analog-to-digital converter, the second analog-to-digital converter and the third analog-to-digital converter convert the analog signals of the atomic fluorescence signal, the laser power signal and the vibration signal into digital signals and upload them to the core processing module.

[0022] In order to realize the miniaturization and field testing of cold atom interferometers, the present invention provides a standardized high-precision acquisition module for cold atom interferometers, which can be used as acquisition modules of cold atom interferometer gyroscopes, cold atom interferometer gravimeters and cold atom interferometer gravity gradiometers, and has the functions of collecting fluorescence collection signals, power-stabilized optical signals and high-precision vibration signals, while ensuring high acquisition accuracy and low acquisition noise, and the module needs to be universal and suitable for most cold atom interferometers.

[0023] Example 1 Embodiment 1 provided by the present invention is an embodiment of a standardized high-precision acquisition module for a cold atom interferometer provided by the present invention, combined with Figure 1 It can be seen that the embodiment of the acquisition module includes: an atomic fluorescence acquisition module, an optical power acquisition module, a vibration acquisition module and a core processing module.

[0024] The atomic fluorescence acquisition module includes: a first analog-to-digital converter for acquiring atomic fluorescence signals; the optical power acquisition module includes: a second analog-to-digital converter for acquiring laser power signals; the vibration acquisition module includes: a third analog-to-digital converter for acquiring vibration signals.

[0025] In a possible embodiment, the atomic fluorescence acquisition module further includes: a photoelectric converter, a second-order low-pass filter module, an operational amplifier scaler, a differential operational amplifier, and a reference source.

[0026] The photoelectric converter collects the atomic fluorescence signal, and the output voltage analog signal passes through the second-order low-pass filter module, the op amp scaling and the differential op amp in sequence, converting the single-ended voltage analog signal into a differential signal, and then inputting the differential signal into the first analog-to-digital conversion chip to convert it into a digital signal and transmit it to the core processing module; the op amp scaling and the differential op amp are used to realize the two-level adjustable amplification gain of the atomic fluorescence acquisition module. The reference source is used to provide a reference voltage for the first analog-to-digital conversion chip.

[0027] In specific implementation, the atomic fluorescence acquisition module collects the atomic fluorescence signal captured by the photoelectric converter, converts it into a digital signal and uploads it to the host computer or embedded system, which then calculates the relevant physical quantities measured by the cold atom interferometer.

[0028] Since the atomic fluorescence signal has the characteristics of weak signal and high sensitivity, a high-precision, low-noise sampling method with a bandwidth greater than 500KHz is required. The sampling signal is filtered through a second-order active low-pass filter, passed through a coefficient adjustable module, and finally converted into a differential signal and input into the analog-to-digital converter. Finally, it is processed by the core processing module or uploaded to the host computer to calculate the final measured physical quantity.

[0029] The second-order low-pass filter module is built by an operational amplifier, and the scaling factor of the fluorescence signal acquisition module can be selected through a multiplexer.

[0030] The first analog-to-digital conversion chip is the core chip, which uses the 16-bit analog-to-digital converter AD9266-20 produced by ADI. This chip is a parallel digital-to-analog conversion chip with a maximum sampling rate of 20Mbps. It has the characteristics of fast sampling rate, simple operation, and high sampling accuracy.

[0031] In a possible implementation manner, the first analog-to-digital conversion chip uses an analog-to-digital converter AD9266-20, and the reference source includes: a reference voltage source LM399 and an inverse proportional amplifier.

[0032] The positive and negative input terminals of the reference voltage source LM399 are connected to positive and negative 12V voltages respectively, the positive output terminal is grounded, and the negative output terminal outputs a negative voltage, which then passes through an inverse proportional amplifier to generate a reference voltage for the first analog-to-digital conversion chip.

[0033] As attached Figure 2 FIG. 1 is a schematic diagram of a reference source reverse connection provided by an embodiment of the present invention, combined with FIG. Figure 2 It can be seen that the reference source outputs a negative voltage, which is then passed through the reverse proportional amplifier to generate a 1V reference signal for the digital-to-analog converter. The reference source has a heating wire that can keep the temperature, making its temperature drift coefficient only 0.5ppm / ℃. If the reference source is not reversed, a positive voltage will be generated. When the op amp is used to scale the signal, the in-phase amplifier cannot reduce the signal. If a 1V voltage reference is required, a two-stage reverse amplifier is required. Therefore, the reverse reference source method can save 1 op amp and 3 resistors, making the reference source circuit simpler and effectively avoiding the risk of noise coupling.

[0034] In a possible implementation manner, the second analog-to-digital conversion chip in the optical power collection module uses an analog-to-digital converter AD9266-20, and the gain of the optical power collection module is fixed.

[0035] The fluorescence signal acquisition module mainly collects optical power signals. Its function is similar to that of an optical power meter, and it has a low-noise and low-bandwidth acquisition function. This module converts the collected analog signals into digital signals and uploads them to the core processing module. The fluorescence signal acquisition module is similar to the optical power stability signal acquisition module, with only one difference: the fluorescence signal acquisition module has an adjustable gain function, with 2-speed adjustable amplification gain, while the optical power stability signal acquisition module has a fixed gain.

[0036] In a possible implementation manner, the vibration collection module further includes: a linear regulator, a differential amplifier module, a proportional amplifier module and a filter module.

[0037] Three linear regulators are used to collect analog signals of vibration signals in the XYZ three-axis directions respectively. The analog signals of the vibration signals pass through the differential amplifier module, the proportional amplifier module and the filtering module in turn, and are collected by the third analog-to-digital converter and converted into digital signals for transmission to the core processing module.

[0038] In a possible implementation manner, the third analog-to-digital converter is an analog-to-digital converter LTC2500-32; the resistors used in the differential amplifier module and the proportional amplifier module are banks of the LT5400 series.

[0039] The vibration acquisition module adopts an isolated power supply solution to isolate all digital and analog signals from other parts of this circuit board. The digital-to-analog converter of the vibration acquisition module uses the 32-bit analog-to-digital converter LTC2500-32 produced by ADI. The chip has an SPI data interface and a maximum sampling rate of 250ksps for 32-bit sampling. It has the characteristics of high acquisition accuracy and easy operation of the output interface. The vibration signal input port is compatible with differential and single-ended inputs. In order to ensure the consistency of the circuit signal, the resistors used in the signal differential amplification and proportional amplification parts of the module are all selected from the LT5400 series, which guarantees the accuracy of the differential signal to the greatest extent. At the same time, the module has a 3rd-order active low-pass filter, which can effectively filter out the noise of the vibration sensor itself. The analog signal of the vibration acquisition module is finally acquired by the analog-to-digital converter after differential, amplification, and filtering, and converted into a digital signal for transmission to the core processor.

[0040] The vibration acquisition module mainly collects vibration information with high precision. The vibration information is generated by the accelerometer or microseismometer signal. The signal is low-frequency but requires extremely high acquisition accuracy, and the vibration signals in the three axes of XYZ must be collected synchronously. In order to ensure the acquisition accuracy of this part, this part is absolutely isolated from other parts of the circuit board. All digital signals are separated by high-isolation isolation chips, and the power supply part is isolated by an isolation power module. This part only forms a loop with the collected object. This method can effectively reduce the impact of other circuits in the system on the acquisition of vibration signals. When collecting channels, low-pass filtering is added. Each collection channel uses a separate high-PSRR linear regulator. At the same time, LC filtering is performed at the output end of the linear regulator to reduce power supply noise and achieve the purpose of reducing acquisition noise. A low-noise and low-drift voltage reference source is used to provide a voltage reference for the analog-to-digital conversion chip. The collected analog signal is converted into a digital signal by the digital-to-analog conversion chip, and then uploaded to the core processing chip through the isolation chip. The core processing chip then calculates the vibration information and compensates the vibration information to the final detected physical quantity.

[0041] The core processing module drives the first analog-to-digital converter, the second analog-to-digital converter and the third analog-to-digital converter to collect the atomic fluorescence signal, laser power signal and vibration signal generated by the cold atom interferometer interference. The first analog-to-digital converter, the second analog-to-digital converter and the third analog-to-digital converter convert the analog signals of the atomic fluorescence signal, the laser power signal and the vibration signal into digital signals and upload them to the core processing module.

[0042] In a possible embodiment, the connector includes: a communication interface, an analog signal interface, and a power input interface.

[0043] The communication interface is used to provide an interface for external communication, and the analog signal interface is used to receive analog signals sent externally; the analog signals include: atomic fluorescence signals, laser power signals and vibration signals; the power input interface is used to receive external input power.

[0044] In a specific implementation, the connector may be a PDS-105 connector.

[0045] In a possible implementation manner, the acquisition module further includes: a power supply module; the power supply module includes: an isolated power supply, a high-frequency DC / DC module, a linear regulator and a multi-channel DC / DC module.

[0046] The isolated power supply outputs two power supplies; one power supply output by the isolated power supply is converted into positive and negative electricity through a high-frequency DC / DC module, and then the positive and negative electricity are converted through a linear regulator to power the analog end; the other power supply output by the isolated power supply is converted through a multi-channel DC / DC module to power the digital end for use by the core processing chip; the power supply module also provides a separate line of isolated power supply for the vibration acquisition module.

[0047] The input power of the circuit board is 24V. The reverse connection protection circuit and surge protection circuit are designed at the power input end. The first-stage power conversion module uses the MGFS402412 isolated DC / DC conversion module produced by COSEL to convert the external input 24V power supply into 12V. The 12V is used as the total power supply of the circuit board to power the core chip, the fluorescence signal acquisition circuit and the optical power signal acquisition circuit. The power supply of the core chip is converted by the integrated high-frequency DC / DC module into 3.3VIO voltage, 1.0V core voltage and 1.8V auxiliary voltage. The fluorescence signal acquisition circuit and the optical signal acquisition circuit use the same power supply scheme, using LTC8049 to convert the input 12V signal into ±12V, and then using the linear regulator LT1963 and LT3015 to convert the voltage into ±10V and +5V to power the analog-to-digital converter and operational amplifier and other devices; the vibration signal acquisition circuit is powered by an isolation module. The vibration collection circuit is isolated from other circuits. The power supply required for the digital-to-analog converter and the power supply required for the operational amplifier are powered by the linear regulator LT3045 and LT3094 chips with high power supply rejection ratio according to the number of collected paths. The multi-level power supply solution enables the system to reduce the coupling of external interference and ensure low-noise power supply for the entire collection module.

[0048] In a possible implementation manner, the core processing module includes: a main control chip; the main control chip is a FMQL10S400 type SOC chip.

[0049] The main control chip is used to drive the atomic fluorescence acquisition module, optical power acquisition module and vibration acquisition module to collect signals, and upload each signal to the host computer after digital filtering; the main control chip is also used to drive each interface to control the information interaction and timing synchronization between the acquisition module and the outside.

[0050] The main function of processing the digital-to-analog converter is to collect data and drive the external interface, process the signals collected by each digital-to-analog converter, and perform corresponding digital filtering on the signal, and finally feed the digital signal back to the digital-to-analog converter or upload it to the host computer.

[0051] The main control chip is the FMQL10S400 SOC chip produced by Shanghai Fudan Microelectronics Co., Ltd., which drives 2 high-speed analog-to-digital converters with adjustable gain coefficients to collect the fluorescence signal of the cold atom interferometer, 2 high-speed analog-to-digital converters with fixed gain coefficients to collect the power-stable optical power signal of the cold atom interferometer, and 3 high-precision digital-to-analog converters to collect the vibration signal of the sensitive unit of the cold atom interferometer; at the same time, the SOC chip also drives serial ports, TTL converters and other interfaces to control information interaction and timing synchronization with the outside.

[0052] In a possible implementation manner, each module of the acquisition module is arranged on a 6U standard board, and the standard board separates the analog area, the digital area, and the high-precision acquisition area.

[0053] All the acquisition functions of the cold atom interferometer are integrated into a 6U standard board. The board is functionally partitioned to separate the analog area, digital area and high-precision acquisition area. The digital area is grounded nearby to ensure that the noise of the digital signal enters the ground first and does not affect the acquisition accuracy of the analog signal. This 6U board unifies all communication interfaces and strengthens all analog signal acquisition functions of the cold atom interferometer. All analog signal interfaces and communication interfaces are unified on the same PDS-105 connector. The module has strong versatility and high-precision clock synchronization.

[0054] A standardized high-precision acquisition module for a cold atom interferometer provided in an embodiment of the present invention integrates all analog model acquisition functions required by a cold atom interferometer system on a 6U board, and can be used in all cold atom interferometer systems; the high-precision acquisition module adopts a completely isolated design, and completely isolates the digital part from the high-precision acquisition part on the same circuit board, effectively reducing the crosstalk between the circuits, improving the acquisition accuracy of the vibration signal, and improving the accuracy of the vibration compensation of the cold atom interferometer; different acquisition systems use different filtering designs and power supply designs, which minimizes the acquisition noise and simplifies the design of the power supply module; all analog signal acquisitions of different types, bandwidths, bits, and sampling rates use the same core processor, which can improve the timing synchronization between different acquisition signals, simplify the interconnection lines between different acquisition modules, and unify the external communication interfaces of different acquisition modules.

[0055] It should be noted that in the above embodiments, the description of each embodiment has its own emphasis, and for parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0056] It will be appreciated by those skilled in the art that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0057] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded computer, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0058] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0059] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0060] Although the preferred embodiments of the present invention have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0061] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A standardized high-precision acquisition module for cold atom interferometer, characterized in that: The acquisition module includes: an atomic fluorescence acquisition module, an optical power acquisition module, a vibration acquisition module and a core processing module; The atomic fluorescence acquisition module includes: a first analog-to-digital converter for acquiring atomic fluorescence signals; the optical power acquisition module includes: a second analog-to-digital converter for acquiring laser power signals; the vibration acquisition module includes: a third analog-to-digital converter for acquiring vibration signals; The core processing module respectively drives the first analog-to-digital converter, the second analog-to-digital converter and the third analog-to-digital converter to collect the atomic fluorescence signal, laser power signal and vibration signal generated by the interference of the cold atom interferometer. The first analog-to-digital converter, the second analog-to-digital converter and the third analog-to-digital converter respectively convert the analog signals of the atomic fluorescence signal, laser power signal and vibration signal into digital signals and upload them to the core processing module.

2. The acquisition module according to claim 1, characterized in that: The atomic fluorescence acquisition module also includes: a photoelectric converter, a second-order low-pass filter module, an operational amplifier scaler, a differential operational amplifier and a reference source; The photoelectric converter collects the atomic fluorescence signal, and the output voltage analog signal is sequentially passed through the second-order low-pass filter module, the operational amplifier scaling and the differential operational amplifier, and the single-ended voltage analog signal is converted into a differential signal, and then the differential signal is input into the first analog-to-digital conversion chip to be converted into a digital signal and transmitted to the core processing module; the operational amplifier scaling and the differential operational amplifier are used to realize the two-level adjustable amplification gain of the atomic fluorescence acquisition module; The reference source is used to provide a reference voltage for the first analog-to-digital conversion chip.

3. The acquisition module according to claim 2, characterized in that: The first analog-to-digital conversion chip uses an analog-to-digital converter AD9266-20, and the reference source includes: a reference voltage source LM399 and an inverse proportional amplifier; The positive and negative input terminals of the reference voltage source LM399 are connected to positive and negative 12V voltages respectively, the positive output terminal is grounded, and the negative output terminal outputs a negative voltage, which then passes through the reverse proportional amplifier to generate the reference voltage of the first analog-to-digital conversion chip.

4. The acquisition module according to claim 1, characterized in that: The second analog-to-digital conversion chip in the optical power acquisition module adopts an analog-to-digital converter AD9266-20, and the gain of the optical power acquisition module is fixed.

5. The acquisition module according to claim 1, characterized in that: The vibration collection module also includes: a linear regulator, a differential amplifier module, a proportional amplifier module and a filter module; The three linear regulators are used to respectively collect analog signals of vibration signals in the three-axis directions of XYZ. The analog signals of the vibration signals pass through the differential amplifier module, the proportional amplifier module and the filtering module in sequence, and are then collected by the third analog-to-digital converter and converted into digital signals for transmission to the core processing module.

6. The acquisition module according to claim 5, characterized in that: The third analog-to-digital converter adopts the analog-to-digital converter LTC2500-32; the resistors used in the differential amplifier module and the proportional amplifier module are banks of the LT5400 series.

7. The acquisition module according to claim 1, characterized in that: The connector includes: a communication interface, an analog signal interface and a power input interface; The communication interface is used to provide an interface for external communication, and the analog signal interface is used to receive analog signals sent externally; the analog signals include: atomic fluorescence signals, laser power signals and vibration signals; the power input interface is used to receive external input power.

8. The acquisition module according to claim 1, characterized in that: The acquisition module also includes: a power supply module; the power supply module includes: an isolated power supply, a high-frequency DC / DC module, a linear regulator and a multi-channel DC / DC module; The isolated power supply outputs two power supplies; one power supply output by the isolated power supply is converted into positive and negative electricity by the high-frequency DC / DC module, and then the positive and negative electricity are converted by the linear regulator to power the analog end; the other power supply output by the isolated power supply is converted by the multi-channel DC / DC module to power the digital end; the power supply module also provides a separate line of isolated power supply for the vibration collection module.

9. The acquisition module according to claim 1, characterized in that: The core processing module includes: a main control chip; the main control chip is a FMQL10S400 SOC chip; The main control chip is used to drive the atomic fluorescence acquisition module, optical power acquisition module and vibration acquisition module to collect signals, and upload each signal to the host computer after digital filtering; the main control chip is also used to drive each interface to control the information interaction and timing synchronization between the acquisition module and the outside.

10. The acquisition module according to claim 1, characterized in that: Each module of the acquisition module is arranged on a 6U standard board, and the standard board separates the analog area, the digital area and the high-precision acquisition area.

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