CN112130003B - Device and method for removing electromagnetic interference signals in same frequency band - Google Patents
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- G—PHYSICS
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- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R29/00—Arrangements for measuring or indicating electric quantities not covered by groups G01R19/00 - G01R27/00
- G01R29/08—Measuring electromagnetic field characteristics
- G01R29/0864—Measuring electromagnetic field characteristics characterised by constructional or functional features
- G01R29/0871—Complete apparatus or systems; circuits, e.g. receivers or amplifiers
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R29/00—Arrangements for measuring or indicating electric quantities not covered by groups G01R19/00 - G01R27/00
- G01R29/08—Measuring electromagnetic field characteristics
- G01R29/0864—Measuring electromagnetic field characteristics characterised by constructional or functional features
- G01R29/0892—Details related to signal analysis or treatment; presenting results, e.g. displays; measuring specific signal features other than field strength, e.g. polarisation, field modes, phase, envelope, maximum value
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- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B19/00—Programme-control systems
- G05B19/02—Programme-control systems electric
- G05B19/04—Programme control other than numerical control, i.e. in sequence controllers or logic controllers
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Abstract
本发明公开了一种去除同频带电磁干扰信号的装置及方法，该装置包括干扰源电流变化检测电路模块、磁传感器信号调理与AD采集电路模块、微处理器、微处理器外围配置电路模块、电压变化与磁场强度数值转化模块、自适应滤波补偿模块和补偿系数标定模块；所述方法采用补偿方法和自适应滤波算法实现消除干扰的目的。本发明通过自适应滤波算法在片上对有用磁信号与干扰磁信号进行分离，有效解决了同频信号混入到传感器感应端后信号无法有效分离的问题，可以实现地磁传感器在较强电磁干扰环境下达到较高的测试精度。
The invention discloses a device and method for removing electromagnetic interference signals of the same frequency band. The device comprises an interference source current change detection circuit module, a magnetic sensor signal conditioning and AD acquisition circuit module, a microprocessor, a microprocessor peripheral configuration circuit module, A voltage change and magnetic field strength numerical conversion module, an adaptive filter compensation module and a compensation coefficient calibration module; the method adopts a compensation method and an adaptive filter algorithm to achieve the purpose of eliminating interference. The invention separates the useful magnetic signal and the interfering magnetic signal on the chip through the adaptive filtering algorithm, effectively solves the problem that the signal cannot be effectively separated after the same frequency signal is mixed into the sensor sensing end, and can realize the geomagnetic sensor in a strong electromagnetic interference environment. achieve high test accuracy.
Description
Technical Field
The invention relates to a test signal processing device and a test signal processing method, in particular to a device and a method for removing electromagnetic interference signals in the same frequency band.
Background
In the existing items such as projectile navigation and trajectory measurement, a multi-sensor fusion miniaturized measurement system is mostly adopted. When the magnetic sensor is used to measure the attitude information, the sensor measurement information is very susceptible to electromagnetic interference generated by a varying current when other circuit modules operate, and a very large error is generated. The circuit working current changes are mostly low-frequency near-zero frequency changes, electromagnetic interference is also low-frequency signals and is mixed with the magnetic signal frequency band containing rocket flight attitude information and transmitted into the sensor end together, the existing processing method for testing signals focuses on signal separation of different frequency bands or frequency points, interference signals are separated from frequency domain filtering, but the processing method cannot be used for processing frequency band mixed signals, and the interference signals are difficult to remove in later calibration. The blind signal separation technology has requirements on the number of sensors and the information source mixing mode, and has no good separation effect on the mixed signals of the same frequency band mixed from the same sensor induction end. And the traditional electromagnetic shielding technology can not effectively shield low-frequency electromagnetic signals and can not achieve the purpose of removing interference by shielding other circuit modules.
Disclosure of Invention
The invention aims to provide a device and a method for removing co-frequency band electromagnetic interference signals, which can inhibit co-frequency electromagnetic interference mixed in a magnetic sensor in combined measurement system application and reduce measurement errors.
The technical scheme for realizing the purpose of the invention is as follows:
a device for removing electromagnetic interference signals with the same frequency band comprises an interference source current change detection circuit module, a magnetic sensor signal conditioning and AD acquisition module, a microprocessor peripheral configuration circuit module and a compensation coefficient calibration module; the microprocessor comprises an AD acquisition interface, a voltage change and magnetic field intensity value conversion module and a self-adaptive filtering compensation module;
the microprocessor is used for operating the algorithms of the voltage change and magnetic field intensity numerical value conversion module and the self-adaptive filtering compensation module;
the interference source current change detection circuit module is used for detecting an interference source current change signal, converting the interference source current change signal into a voltage change signal and inputting the voltage change signal into an AD acquisition interface of the microprocessor;
the AD acquisition interface performs analog-to-digital conversion and sends the analog-to-digital conversion to the voltage change and magnetic field intensity value conversion module;
the compensation coefficient calibration module is used for calibrating a compensation coefficient K and inputting the compensation coefficient K into the voltage change and magnetic field intensity numerical value conversion module;
the voltage change and magnetic field intensity value conversion module outputs interference signals to the self-adaptive filtering compensation module;
the magnetic sensor signal conditioning and AD acquisition module is used for measuring an actual magnetic field intensity signal, performing analog-to-digital conversion on the actual magnetic field intensity signal and inputting the actual magnetic field intensity signal to the adaptive filtering compensation module;
the self-adaptive filtering compensation module removes interference signals in the input signals through a filtering algorithm;
the peripheral configuration circuit module of the microprocessor comprises a clock circuit module, a reset circuit module and a power management module and is used for providing power, reset signals and an external clock for the microprocessor.
Furthermore, the interference source current change detection circuit module comprises a power supply input, an interference power supply circuit module and a detection resistor RiAnd a subtraction circuit module; the power input is connected to the subtraction circuit module and the detection resistor RiOne end of (1), detecting the resistance RiThe other end is connected with the input ends of the subtraction circuit module and the interference source circuit module, the output end of the interference source circuit module is grounded, and the output of the subtraction circuit is a detection resistor RiThe voltage difference across them.
Further, the method can be used for preparing a novel materialThe subtraction circuit module comprises a first resistor R1A second resistor R2A third resistor R3A fourth resistor RfAnd operational amplifier a 1; a first resistor R1One end of the resistor is connected with the power supply input end, and the other end of the resistor is connected with the non-inverting input end of the operational amplifier A1 and the fourth resistor RfOne end connected to a fourth resistor RfThe other end is connected with the output end of the operational amplifier A1, and a second resistor R2One terminal and a detection resistor RiConnected to the other end of the resistor, and the inverting input terminal of the operational amplifier A1 and the third resistor R3Is connected to a third resistor R3And the other end thereof is commonly grounded to the ground terminal of the operational amplifier a 1.
Further, the detection resistor RiIs a1 omega resistance.
Further, the first resistor R1A second resistor R2A third resistor R3And a fourth resistor RfThe resistance values of the two are the same.
Furthermore, the magnetic sensor signal conditioning and the magnetic sensor measurement signal collected by the AD collection module are transmitted to the microprocessor in parallel through the bus.
Further, the microprocessor employs an STM32f4x chip.
A method for removing electromagnetic interference signals in the same frequency band adopts a compensation method and an adaptive filtering algorithm, and the method for removing the electromagnetic interference signals in the same frequency band specifically comprises the following steps:
the compensation coefficient calibration module obtains a compensation coefficient K through a calibration method;
the signal conditioning and AD acquisition module of the magnetic sensor outputs a quantized value V of the magnetic signal to be detected mixed with electromagnetic interference1；
The output of the interference source current change detection circuit module is subjected to AD conversion in the microprocessor to obtain an interference voltage AD sampling value V0；
Sampling value V0The compensation coefficient K is input into a voltage change and magnetic field intensity value conversion module, and the microprocessing is carried out by sampling a value V0Calculating with the compensation coefficient K to obtain the module interference signal E1CalculatingFormula E1＝V0×K；
V1And interference signal E1The signal is input to the adaptive filtering compensation module, and the signal without interference is output after being filtered by the adaptive filtering compensation module.
Further, the calibration method specifically comprises the following steps:
the device for removing the same-frequency electromagnetic interference signals is assembled and placed at a fixed position and posture;
initializing a compensation coefficient K to be 1;
the device works, a magnetic sensor signal conditioning and AD acquisition module acquires an original signal value M1 of a magnetic sensor, and an interference source current change detection module acquires an original value Vn of an interference signal;
fixing the magnetic field intensity to be measured under the standing condition, and storing a time domain waveform diagram of M1 and Vn;
obtaining delta M1 according to a time domain waveform diagram of M1, wherein delta M1 is a variation peak value of the electromagnetic interference signal; obtaining delta Vn according to a time domain oscillogram of Vn, wherein the delta Vn is a voltage change peak value of the electromagnetic interference source;
and calculating a compensation coefficient K of the two, wherein the calculation formula of K is as follows:
compared with the prior art, the invention has the beneficial effects that the invention adopts hardware design to collect and calibrate the output electromagnetic interference signal, separates the useful magnetic signal from the interference magnetic signal through the compensation method and the adaptive filtering algorithm, effectively solves the problem that the signal can not be effectively separated after the same frequency signal is mixed into the sensor induction end, and ensures the authenticity and the accuracy of the measurement result to the maximum extent.
Drawings
Fig. 1 is a schematic diagram of the overall framework of the device of the present invention.
Fig. 2 is a circuit diagram of a current variation detection circuit of an interference source according to the present invention.
FIG. 3 is a block diagram of a microprocessor and peripheral configuration circuitry according to the present invention.
FIG. 4 is a schematic diagram of the method for removing electromagnetic interference in the same frequency band of signals according to the present invention.
FIG. 5 is a schematic diagram of a calibration method of the compensation coefficient calibration module according to the present invention.
FIG. 6 is a waveform diagram of raw signal data of a magnetic sensor according to the present invention.
Fig. 7 is a waveform diagram of the magnetic sensor signal collected by the invention after interference is removed.
In the figure: 1. the device comprises an interference power supply circuit module, a detection resistor, a subtraction circuit module, a clock circuit module, a reset circuit module, a power supply management module, a microprocessor, a magnetic sensor signal conditioning and AD acquisition module, a power supply current change detection module, a power supply voltage and magnetic intensity value conversion module, an interference voltage and magnetic intensity value conversion module, a compensation coefficient K, a compensation coefficient AD, a clock circuit module, a reset circuit module, a power supply management module, a microprocessor, a power supply voltage and magnetic intensity value conversion module, a clock circuit module, a reset circuit module, a power supply management module, a clock circuit module, a microprocessor, a clock circuit module, a reset circuit module, a clock circuit module, a microprocessor, a clock circuit module, a clock circuit module, a clock module, a.
Detailed Description
The following describes an apparatus and a method for removing electromagnetic interference signals in the same frequency band in detail with reference to the drawings.
As shown in fig. 1, a device for removing electromagnetic interference signals with the same frequency band comprises an interference source current change detection circuit module, a magnetic sensor signal conditioning and AD acquisition module, a microprocessor peripheral configuration circuit module and a compensation coefficient calibration module; the microprocessor comprises an AD acquisition interface, a voltage change and magnetic field intensity value conversion module and a self-adaptive filtering compensation module;
the microprocessor is used for operating the algorithms of the voltage change and magnetic field intensity numerical value conversion module and the self-adaptive filtering compensation module; the interference source current change detection circuit module is used for detecting an interference source current change signal, converting the interference source current change signal into a voltage change signal, sending the voltage change signal into an AD acquisition interface of the microprocessor, carrying out analog-to-digital conversion by the AD acquisition module, sending the voltage change signal into the magnetic field intensity value conversion module, inputting the compensation coefficient calibration module into the voltage change and magnetic field intensity value conversion module according to a compensation coefficient K, and outputting the interference signal to the adaptive filtering compensation module by the voltage change and magnetic field intensity value conversion module; the magnetic sensor signal conditioning and AD acquisition interface is used for measuring an actual magnetic field intensity signal, performing analog-to-digital conversion on the actual magnetic field intensity signal and inputting the actual magnetic field intensity signal to the adaptive filtering compensation module. The adaptive filtering compensation module is used for outputting a signal for removing interference; the compensation coefficient calibration module is used for calculating a proportionality coefficient K in the voltage change and magnetic field intensity numerical value conversion module; the microprocessor peripheral configuration circuit module is used for providing power supply, reset signals and external clocks for the microprocessor.
The interference source current change detection circuit module comprises a power supply input, an interference power supply circuit module 1, a detection resistor 2 and a subtraction circuit module 3, wherein FIG. 2 is a circuit diagram of the interference source current change detection circuit module, and the detection resistor RiA1 omega resistor, one end of which is connected with the power input end of the circuit module with current change, and the other end of which is connected with a second resistor R2Connecting; a first resistor R1A second resistor R2A third resistor R3A fourth resistor RfAnd an operational amplifier A1 to form a subtraction circuit module 3, wherein R1、R2、R3And RfThe resistance values are the same; one end of R1 is connected with the power input end, and the other end is connected with the non-inverting input end of the operational amplifier A1 and the fourth resistor RfOne end connected to a fourth resistor RfThe other end is connected with the output end of the operational amplifier A1, and a second resistor R2One terminal and a detection resistor RiConnected to the other end of the resistor, and the inverting input terminal of the operational amplifier A1 and the third resistor R3One end connected to a third resistor R3Is commonly grounded with the ground terminal of the operational amplifier a1, and the output of the interference source current change detection circuit is Uout，UoutIs RiThe difference Δ V of the voltages at both ends; Δ V is linearly proportional to the change Δ I of the current of the interference source, i.e., Δ V ═ Rix.DELTA.I, and because of RiSince 1 Ω, Δ V is Δ I.
FIG. 3 is a schematic diagram of a microprocessor and a peripheral configuration circuit module of the microprocessor, wherein the peripheral configuration circuit module of the microprocessor includes a clock circuit module 4, a reset circuit module 5 and a power management module 6; after the signal conditioning and AD collecting module 8 of the magnetic sensor collects the signal measured by the magnetic sensor, the signal is transmitted to the microprocessor in parallel through the bus W1; the microprocessor 7 adopts an STM32f4x chip to disturb the source currentOutput signal U of change detection circuit module 9outThe analog signal input end of the 12-bit ADC of the STM32f4x is connected to complete analog-to-digital conversion;
based on the above device, a method for removing electromagnetic interference signals in the same frequency band adopts a compensation method and an adaptive filtering algorithm to achieve the purpose of eliminating interference, as shown in fig. 4, the method for removing electromagnetic interference signals in the same frequency band is as follows:
the compensation coefficient calibration module obtains a compensation coefficient K through a calibration method;
the magnetic sensor signal conditioning circuit and the AD acquisition module output a quantized value V of the magnetic signal to be detected mixed with electromagnetic interference1The waveforms of the original signals of the magnetic sensor collected by the signal conditioning circuit of the magnetic sensor and the AD collection module are shown in FIG. 6;
output U of interference source current change detection circuit moduleoutFinishing AD conversion in a microprocessor to obtain an interference voltage AD sampling value V0. Will V0The compensation coefficient K is input into a voltage change and magnetic field intensity value conversion module 10, and the microprocessing is carried out by sampling values V0Calculating with the compensation coefficient K to obtain the module interference signal E1。E1＝V0xK, where K is the compensation factor.
V1And interference signal E1The signal is input to the adaptive filtering compensation module 12, filtered by the adaptive filtering compensation module 12, and then the signal without interference is output, and a waveform diagram of the signal without interference is shown in fig. 7.
The calibration method of the compensation coefficient calibration module is shown in fig. 5, and specifically includes:
the device is assembled and stands still for a fixed position and posture, and the electromagnetic interference direction and the intensity change range generated by the interference module are fixed;
initializing a compensation coefficient K to be 1;
the device works, a magnetic sensor signal conditioning and AD acquisition module acquires an original value M1 of a magnetic sensor, and an interference source current change detection module acquires an original value Vn of an interference signal;
the magnetic field intensity to be measured is fixed under the standing condition, the change of M1 comes from an electromagnetic field generated by a circuit module with current change, and the time domain waveforms of M1 and Vn are observed, and the waveform changes in the same way, but the amplitude value is different or the direction is different.
Measuring and storing data of M1 and Vn under the standing condition, and obtaining delta M1 according to the waveform change of M1, wherein the delta M1 is the change peak value of the electromagnetic interference signal; Δ Vn is the peak of the voltage change of the electromagnetic interference source.
And calculating a compensation coefficient K of the two, wherein the calculation formula of K is as follows:
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| CN113252960A (en) * | 2021-04-30 | 2021-08-13 | 南京工程学院 | External magnetic field interference suppression method suitable for direct-current power distribution network current sensor |
| CN113341351A (en) * | 2021-06-08 | 2021-09-03 | 广东技术师范大学 | Omnidirectional magnetic induction intensity testing instrument calibration and time-frequency testing method and device |
| US20240364643A1 (en) | 2023-04-28 | 2024-10-31 | Intel Corporation | Technologies for processing packets on a network interface controller with high-bandwidth memory chiplets |
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Effective date of registration: 20230803 Address after: No. 68, Lane 6, Lincheng Industrial Park, Lincheng Street, Dinghai District, Zhoushan City, Zhejiang Province, 316021 Patentee after: ZHEJIANG ZHONGYU COMMUNICATION Co.,Ltd. Address before: 210094 No. 200, Xiaolingwei, Jiangsu, Nanjing Patentee before: NANJING University OF SCIENCE AND TECHNOLOGY |
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Denomination of invention: A device and method for removing electromagnetic interference signals in the same frequency band Granted publication date: 20211109 Pledgee: Bank of China Limited Zhoushan Putuo Branch Pledgor: ZHEJIANG ZHONGYU COMMUNICATION Co.,Ltd. Registration number: Y2024330001704 |