An adaptive low-energy particle detection system

Abstract

The application provides a self-adaptive low-energy particle detection system, comprising a low-energy ion analyzer and a low-energy electron analyzer, and both analyzers adopt a same FPGA control program; in the FPGA design, component grouping measurement is added, which is used for realizing multi-component detection in a unit measurement time; in the interface, an instrument number interface is added, which is used for reading the instrument number interface level; a number identification and control module is added, which is used for identifying a current instrument type, generating an instrument identification parameter, realizing collection of different path engineering parameters when the instrument type is the low-energy ion analyzer or the low-energy electron analyzer, controlling reception of an instruction of a device where a current FPGA configuration item is located, and further used for controlling output of a data packet of the device where the current FPGA configuration item is located. The system of the application burns and writes a same FPGA executable code on the low-energy ion analyzer and the low-energy electron analyzer, two different devices, and realizes FPGA configuration item self-adaptation.

Description

[0001] This application is a divisional application of the invention application No. 202510267018.6, with the title of "Multi-component charged particle detection system", and the application date of March 7, 2025. TECHNICAL FIELD

[0002] The present application belongs to the key technical field of space plasma detection, and specifically relates to a self-adaptive low-energy particle detection system. BACKGROUND

[0003] Charged particle analyzers are an important part of space environment detectors. With the development of technology, the requirements for detectors in deep space exploration are gradually increasing, and the charged particle analyzers are required to have a large field of view and multi-component detection function. A large field of view can be achieved by multiple detectors distributed in different positions of the satellite for synchronous detection; multi-component can be achieved by multiple detectors detecting different components, or a single device detecting different components at different times. The large field of view / multi-component detection has very high requirements for the FPGA design of the detector.

[0004] Low-energy ion analyzers and low-energy electron analyzers are important components of charged particle detectors, which can detect different components, and the main detection objects are low-energy ions and low-energy electrons. The low-energy ion analyzer is used to measure positively charged ions and distinguish different components of the ions, and the low-energy electron analyzer is used to measure negatively charged electrons. The charge polarities detected by the two are opposite, and the hardware circuit is required to generate high voltage with opposite polarity, so the low-energy ion analyzer and the low-energy electron analyzer hardware circuit cannot be combined, and two different single machines need to be designed to realize the detection of low-energy ions / low-energy electrons. The functions and performances of the FPGA configuration items of the low-energy ion analyzer and the low-energy electron analyzer are similar, and the external interfaces are different.

[0005] The current developed low-energy ion analyzer cannot distinguish the components of ions in space, and the FPGA configuration items of the low-energy ion analyzer and the low-energy electron analyzer are independent of each other, and two instruments are configured with: FPGA configuration item managers, designers, and testers. The design and testing of the FPGA configuration items of the instruments have poor consistency, and a large amount of manpower and development cost is consumed. SUMMARY

[0006] The purpose of the present application is to overcome the single detection component function of the existing low-energy ion analyzer and low-energy electron analyzer, and the independent development of the FPGA configuration items of each device, which causes the defect of excessive maintenance of the FPGA configuration items.

[0007] In order to achieve the above purpose, the present application provides a self-adaptive low-energy particle detection system, which comprises a low-energy ion analyzer and a low-energy electron analyzer.

[0008] The instrument number in the communication protocol between the low-energy ion analyzer and the low-energy electron analyzer and external equipment is different;

[0009] An instrument number interface is added in the interface of the FPGA of the low-energy ion analyzer and the low-energy electron analyzer, for reading the instrument number interface level;

[0010] An instrument number identification and control module is added in the FPGA of the low-energy ion analyzer and the low-energy electron analyzer, for obtaining the instrument number interface level from the instrument number interface, identifying the current instrument type, and generating an instrument identification parameter; for controlling an engineering parameter acquisition module to acquire different numbers of engineering parameters when the instrument type is a low-energy ion analyzer or a low-energy electron analyzer; for controlling a data receiving, analyzing and responding module to receive instructions conforming to the device in which the current FPGA configuration item is located, record errors and ignore the instructions when instructions of other instruments are received; and for controlling a data packaging and sending module to output data packets conforming to the device in which the current FPGA configuration item is located.

[0011] As an improvement of the above system, when the instrument type is a low-energy ion analyzer, 16 channels of engineering parameters are acquired, and when the instrument type is a low-energy electron analyzer, 12 channels of engineering parameters are acquired.

[0012] As an improvement of the above system, the system further comprises:

[0013] A timing control function is added in the scientific data acquisition module of the FPGA of the low-energy ion analyzer and the low-energy electron analyzer, the minimum detection time unit is divided into multiple component detection time units, and the length of time of the output gate high-voltage switch of the high-voltage circuit is controlled to be different in different time units, so that the detection of different components is realized.

[0014] As an improvement of the above system, the system further comprises:

[0015] The interface of the FPGA of the low-energy ion analyzer and the low-energy electron analyzer further comprises a crystal oscillator, an SRAM interface, an MRAM interface, a multi-channel switch interface, an AD conversion circuit interface, an asynchronous serial RS422 interface, a high-voltage power supply control interface, a DA conversion interface, a preamplifier interface and a time-of-flight measurement chip interface.

[0016] As an improvement of the above system, the system further comprises:

[0017] The modules of the FPGA of the low-energy ion analyzer and the low-energy electron analyzer further comprise a scientific data acquisition module, a scientific data processing module, a working parameter table reading and writing module, a high-voltage power supply control module, an adjustment preamplifier threshold module, an output preamplifier test signal module and a system time keeping and timing control module.

[0018] Compared with the prior art, the application has the following advantages:

[0019] 1、The application innovatively adds a time sequence control function, combines the principle that the switch gate length of the high-voltage circuit can control the entry of ions of a certain component, divides the minimum detection time unit into multiple component detection time units, controls the output gate high-voltage switch length of the high-voltage circuit to be different in different time units, and realizes the detection of different components.

[0020] 2、The application increases the instrument number identification and control function, cooperatively designs the hardware interface circuit and the FPGA configuration item, realizes the FPGA configuration item self-adaptation, the FPGA configuration item identifies the current single machine by reading the instrument number interface level, controls the "injection instruction receiving, analysis and response", "engineering parameter acquisition", "data packaging and sending" function modules to perform the related functions according to the device where the current FPGA configuration item is located. The application effectively avoids the waste of human resources, reduces the FPGA configuration item development cost, and improves the consistency of the operation of the FPGA configuration items of multiple devices. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 Fig. 1 shows the interface block diagram of the low-energy ion analyzer and the low-energy electron analyzer and the load management unit;

[0022] Figure 2 Fig. 2 shows the FPGA external interface block diagram for adaptive low-energy particle detection;

[0023] Figure 3 Fig. 3 shows the FPGA product function diagram for adaptive low-energy particle detection;

[0024] Figure 4 Fig. 4 shows the component detection time sequence diagram of the FPGA for adaptive low-energy particle detection. DETAILED DESCRIPTION

[0025] The technical solutions of the application will be described in detail below with reference to the drawings.

[0026] The adaptive low-energy particle detection system provided by the application is based on the improvement of the existing low-energy ion analyzer and low-energy electron analyzer, and the multiple device self-identification and execution function modules are added in the FPGA, which overcomes the problem that the FPGA configuration items of the current multiple charged particle analyzers are designed independently, resulting in poor design state consistency and waste of human resources. In the application, the low-energy ion analyzer and the low-energy electron analyzer hardware circuit are respectively designed with an instrument number ID interface. After the FPGA power reset is completed, the instrument number ID interface level is actively read, the current single machine is identified, the instrument number is generated, each function module is executed according to the FPGA requirement specification, and communication is performed according to the external communication protocol.

[0027] The improved FPGA is used in the low-energy ion analyzer and the low-energy electron analyzer in the adaptive low-energy particle detection system provided in the application. In ion detection, the original indistinguishable ion components are changed to distinguishable hydrogen ion (H+), helium ion (He++, He+), oxygen ion (O++) and other components. The low-energy ion analyzer and the low-energy electron analyzer share the FPGA configuration item, as shown in Table 1. The FPGA designers are changed from two to one, the ground inspection designers are changed from two to one, the single machine testers are changed from two to one, the design / test equipment is changed from two sets to one set, the FPGA configuration item third-party evaluation outsourcing cost is reduced to 1 / 2 of the original, not only the outsourcing cost and the design / test equipment are reduced, a large amount of manpower is saved, but also the internal functions, performances and interfaces of the two instruments are realized by the same FPGA program, and the two instruments have high consistency.

[0028] Table 1 Comparison of workloads before and after using the improved FPGA

[0029]

[0030]

[0031] In the embodiment, the low-energy ion analyzer is responsible for detecting the composition, energy, direction and flux of ions in the space environment, and the low-energy electron analyzer is responsible for detecting the energy, direction and flux of electrons in the space environment. The two instruments have independent functions and have independent interfaces with the payload management unit (PMU). The low-energy ion analyzer, the low-energy electron analyzer and the payload management unit are independent devices, and each device has one FPGA.

[0032] As shown in Figure 1 , the interfaces of the payload management unit with the low-energy ion analyzer and the low-energy electron analyzer each include a power supply interface, an analog telemetry interface and an asynchronous serial RS422 communication interface. The hardware interface circuit design states are completely consistent.

[0033] The payload management unit provides primary power for the low-energy ion analyzer and the low-energy electron analyzer through the power supply interface, respectively collects the analog telemetry input by the two instruments through the analog telemetry interface, and performs RS422 communication with the two devices through the asynchronous serial RS422 communication interface. In order to distinguish the two instruments, the instrument identifiers (instrument numbers) in the RS422 communication protocols of the PMU and the two instruments are different, and the functions of the two instruments are completely consistent. Table 2 shows a difference statistics table of the low-energy ion analyzer and the low-energy electron analyzer.

[0034] Table 2 Difference statistics table of the low-energy ion analyzer and the low-energy electron analyzer

[0035]

[0036] As Figure 2 shown, the external interface of the FPGA configuration item for adaptive low-energy particle detection includes: crystal oscillator, SRAM interface, MRAM interface, multiplexer interface, AD conversion circuit interface, asynchronous serial RS422 interface, high-voltage power supply control interface, DA conversion interface, preamplifier interface, time-of-flight measurement chip interface, and instrument number interface. The instrument number interface is a newly added interface of the present application, and the other interfaces are the interfaces of the original FPGA configuration item.

[0037] The FPGA configuration item for adaptive low-energy particle detection contains 11 functional modules, the functional module descriptions are shown in Table 3, and the top-level data flow modules are shown in Figure 3 .

[0038] Table 3 Functional description of 11 functional modules of FPGA configuration item

[0039]

[0040] The instrument number identification and control module is a newly added module of the present application, and the other modules are the modules of the original FPGA configuration item.

[0041] The power-on reset and initialization design, normal detection cycle operation design, and instruction receiving design of the FPGA configuration item for adaptive low-energy particle detection are as follows:

[0042] 1) Power-on reset and initialization

[0043] When the FPGA for adaptive low-energy particle detection starts to work, the instrument is powered on, and after the program is loaded, the FPGA will reset each module for 2s. The reset process is as follows: the reset signal becomes low, and each state machine and register completes the reset according to the FPGA program design.

[0044] In the FPGA configuration item for adaptive low-energy particle detection, an instrument number identification and control module is added. After the instrument is powered on and completes the power-on reset, the module actively reads the instrument number interface level, identifies the current instrument, and generates an "instrument identification" parameter. The "acquisition parameter" is used to control the engineering parameter acquisition module to realize the acquisition of 16 channels of engineering parameters by the low-energy ion analyzer and the acquisition of 12 channels of engineering parameters by the low-energy electron analyzer. The "instrument identification" is used to control the data receiving, analysis, and response module to receive instructions that conform to the device where the current FPGA configuration item is located, record errors when receiving instructions from other instruments, and ignore the instructions. The "instrument number / packet information" is used to control the data packet sending module to output data packets that conform to the device where the current FPGA configuration item is located.

[0045] 2) Normal detection cycle operation

[0046] The working cycle of FPGA for adaptive low-energy particle detection is 2s, and the scientific data acquisition instruction sent by PMU through RS422 starts the working cycle. After receiving, analyzing and responding to the scientific data acquisition instruction from PMU, the module opens a detection cycle, and controls the data packaging and sending module to send the scientific data and engineering parameters of the previous working cycle. In a detection cycle, the FPGA control working parameter table reading and writing module reads the data in the MRAM in turn, and updates the internal instrument control parameters (timing control parameters, high voltage parameters, data preprocessing parameters, compression flag). The system time keeping and timing control module controls the instrument running time according to the timing control parameters read from the MRAM, and realizes the time-sharing detection of different component ions / electrons; the high voltage power supply control module controls the high voltage circuit according to the high voltage parameters, and outputs the high voltage required by the sensor; the preamplifier threshold adjustment module configures the DA output preamplifier threshold according to the threshold parameter, and the scientific data acquisition module pre-processes the time-of-flight data collected according to the data preprocessing parameters, and outputs the data to the scientific data processing module after grouping by azimuth angle, mass component, energy channel and pitch angle; the scientific data processing module performs logarithmic and lossless compression on the scientific data according to the compression flag, and outputs the processed data to the data packaging and sending module, which stores the data in the external SRAM. In each working cycle, FPGA controls the engineering parameter acquisition module to collect analog engineering parameters according to the acquisition parameter information, and caches the engineering parameters in the FPGA internal RAM. After FPGA receives the scientific data acquisition instruction again, it starts a new working cycle, and at the same time, it caches the scientific data and engineering parameters of the previous working cycle according to the instrument number and data packaging protocol given by the instrument number identification and control module, and sends the data to PMU through RS422. The FPGA working process is sequentially cycled according to the above process. The FPGA receives the scientific data acquisition instruction sent by PMU for the first time after starting, does not send data, and only starts a cycle of work.

[0047] As Figure 4As shown, in the FPGA for adaptive low-energy particle detection, each detection cycle contains a plurality of minimum detection units, different pitch angle control high voltage and energy channel control high voltage are configured in each detection unit to realize scanning detection of pitch angle and energy channel. In the application, the minimum detection unit is further divided into different component detection units, and the principle of controlling and determining the entry of ions of different components by the switching door duration of the gate high voltage circuit is combined to realize the detection of different components. The specific implementation scheme is as follows: first, according to the principle of controlling and determining the entry of ions of different components by the switching door duration of the gate high voltage circuit, the time T1 required for ions of different components to pass through a gate control region of a fixed length and the time T2 of a fixed length free flight region are obtained through simulation calculation, and the simulation obtained time parameters (T1, T2) are written into the MRAM as high voltage parameters and data preprocessing parameters. The minimum detection time unit is divided into a plurality of component detection time units by the scientific data acquisition module, in each time unit, the high voltage power supply control module controls the opening time of the gate high voltage according to the high voltage parameters, that is, allows the target ions to enter the detection region, and the scientific data acquisition module measures the ions of the target mass group according to the data preprocessing parameters in different component detection time units, and transmits the detection data to the scientific data processing module in groups, and finally realizes multi-component detection.

[0048] 3) Instruction receiving

[0049] The scientific data acquisition instruction sent by the PMU is used to control the instrument to start a new working cycle, the working cycle of the instrument is 2s, when the interval of the scientific data acquisition instructions is greater than 2s, the FPGA starts a new working cycle according to the received scientific data acquisition instruction each time, and simultaneously sends a data packet, when the interval of the scientific data acquisition instructions is less than 2s, the FPGA ignores the received scientific data acquisition instructions within 2s.

[0050] The injection data instruction sent by the PMU can be received and analyzed by the FPGA at any time, and the response can be completed within a specified time, the correct instruction returns a correct response, and the incorrect instruction returns an error response. The FPGA can control the test signal output by receiving the injection data test signal parameter sent by the PMU, and can write the instrument control parameters (timing control parameters, high voltage parameters, data preprocessing parameters, compression flags) into the MRAM by receiving the injection data MRAM write parameter. When the FPGA works for the first time, the MRAM parameter writing should be completed before the scientific data acquisition instruction starts the working cycle, and the data in the MRAM will not be lost during power failure.

[0051] The instrument has an injection control working mode and a working parameter table control mode, in the working parameter table control mode, the high voltage circuit control and the preamplifier threshold control of the instrument are controlled by the parameters in the MRAM, and the FPGA only receives the high voltage enable setting and the threshold setting instruction without executing them.

[0052] The instrument works in injection control mode. When receiving the high voltage enable setting parameter of the injection data sent by the PMU, the high voltage circuit can output the set high voltage. When receiving the threshold setting parameter of the injection data sent by the PMU, the DA output preamplifier threshold voltage can be controlled.

[0053] The time code instruction sent by the PMU is not responded after being received by the FPGA, and is only used for updating the time information of the system time keeping and timing control module.

[0054] Finally, it should be noted that the above examples are only used to illustrate the technical solutions of the present application and are not limiting. Although the present application has been described in detail with reference to the examples, those skilled in the art should understand that modifications or equivalent replacements of the technical solutions of the present application do not deviate from the spirit and scope of the present application, and they should be covered in the scope of the claims of the present application.

Claims

1. An adaptive low-energy particle detection system comprising a low-energy ion analyzer, a low-energy electron analyzer and a load management unit; characterized in that, the instrument number in the communication protocol of the low-energy ion analyzer and the low-energy electron analyzer is different from that of external devices; an instrument number interface is added to the interface of the FPGA of the low-energy ion analyzer and the low-energy electron analyzer for reading the instrument number interface level; a number identification and control module is added to the FPGA of the low-energy ion analyzer and the low-energy electron analyzer for obtaining the instrument number interface level from the instrument number interface, identifying the current instrument type, generating an instrument identification parameter, controlling the engineering parameter acquisition module to acquire different numbers of engineering parameters when the instrument type is a low-energy ion analyzer or a low-energy electron analyzer, controlling the data receiving, analysis and response module to receive instructions conforming to the device in which the current FPGA configuration item is located, record errors and ignore the instructions when instructions of other instruments are received, and further controlling the data packet output module to output data packets conforming to the device in which the current FPGA configuration item is located; a timing control function is added to the scientific data acquisition module of the FPGA of the low-energy ion analyzer and the low-energy electron analyzer, the minimum detection time unit is divided into multiple component detection time units, and the output time of the gate high-voltage switch of the high-voltage circuit is controlled to be different in different time units, i.e. allowing target ions to enter the detection region, the scientific data acquisition module measures ions of a target mass group according to data preprocessing parameters in different component detection time units, and transmits the detection data to the scientific data processing module in groups to realize detection of different components; the FPGA of the low-energy ion analyzer and the low-energy electron analyzer further comprises a scientific data acquisition module, a scientific data processing module, a working parameter table read-write module, a high-voltage power supply control module, an adjustment preamplifier threshold module, an output preamplifier test signal module and a system time keeping and timing control module.

2. The adaptive low-energy particle detection system of claim 1, wherein, When the instrument type is a low-energy ion analyzer, 16 channels of engineering parameters are acquired, and when the instrument type is a low-energy electron analyzer, 12 channels of engineering parameters are acquired.

3. The adaptive low-energy particle detection system of claim 1, wherein, Further comprising: the interface of the FPGA of the low-energy ion analyzer and the low-energy electron analyzer further comprises a crystal oscillator, an SRAM interface, an MRAM interface, a multi-channel switch interface, an AD conversion circuit interface, an asynchronous serial RS422 interface, a high-voltage power supply control interface, a DA conversion interface, a preamplifier interface and a time-of-flight measurement chip interface.

Images