An airborne Hall signal processing system suitable for long-distance strong interference environment

Abstract

The application provides an airborne Hall signal processing system suitable for long-distance strong interference environment, comprising: a surge protection unit for discharging lightning surge energy and overvoltage clamping protection of input three-phase Hall signals; an optoelectronic isolation unit for implementing electrical isolation of front and rear circuits; a low-pass filter unit for filtering high-frequency crosstalk noise carried in the three-phase Hall signals output by the optoelectronic isolation unit; a Schmitt trigger unit for hysteresis shaping of the three-phase Hall signals output by the low-pass filter unit; and a push-pull drive unit for power amplification of the three-phase Hall signals output by the Schmitt trigger unit, and for implementing transient interference suppression by using device characteristics. The application solves problems such as easy noise flooding of original Hall signals, signal distortion caused by long-line transmission ground loop common-mode interference, power line high-frequency coupling crosstalk intrusion into signal path, signal edge jitter and burr induced back-end circuit mis-triggering and the like.

Description

Technical Field

[0001] This invention belongs to the field of avionics technology, and specifically relates to an airborne Hall signal processing system suitable for long-distance, high-interference environments. Background Technology

[0002] Hall effect sensors, due to their non-contact and highly reliable characteristics, are widely used in aerospace control systems such as airborne electromechanical actuators and servo position feedback, providing core position signals for precise motor commutation and closed-loop rotor position control. However, in the complex electromagnetic environment of airborne systems, long-distance transmission of Hall effect signals faces multiple technical bottlenecks, directly restricting the stability of aerospace control systems: First, the dispersed layout of airborne equipment, with Hall signal transmission lines typically exceeding 15 meters in length, leads to signal attenuation, waveform distortion, and edge timing broadening, severely compromising signal integrity. Second, the co-laying of signal and power lines allows strong interference from the power circuit to easily crosstalk into the signal path through distributed capacitance coupling and electromagnetic induction. Third, the airborne environment is subject to strong electromagnetic disturbances such as lightning surges and ground loop common-mode interference. These long-distance, high-interference environments can easily cause rotor position misjudgments and motor commutation timing errors, resulting in electromechanical actuator malfunctions and starting failures, directly impacting the operational safety of airborne equipment.

[0003] Chinese patent [A cable connecting an aircraft electric brake controller and an electromechanical actuator, CN201410143797.0, authorized, published on August 13, 2014] addresses electromagnetic compatibility issues by optimizing the cable structure. It employs multi-layer shielding and group isolation to physically separate the force sensor core, Hall sensor core, and the three-phase motor core. However, this solution primarily relies on passive protection of the transmission medium. If the interference intensity exceeds the suppression capability of the shielding layer, signal quality cannot be guaranteed. Furthermore, the multi-layer shielding structure increases cable weight and manufacturing costs, contradicting the lightweight requirements of airborne equipment.

[0004] The core idea of ​​the Chinese patent [A Long-Distance Lossless Signal Transmission Device for Motors, CN202322287986.2, authorized, published on May 14, 2024] is to convert voltage signals into current signals for long-distance transmission, effectively reducing line voltage drop interference and improving signal attenuation resistance. However, this solution changes the original voltage signal transmission standard, resulting in high hardware modification complexity and poor compatibility; the 4mA basic bias current brings continuous static power consumption; and the cable loop inductance and parasitic capacitance form a natural low-pass filtering effect, resulting in limited signal transmission bandwidth and inability to adapt to the requirements of high-frequency Hall signal transmission. Summary of the Invention

[0005] The purpose of this invention is to overcome the above-mentioned shortcomings of the prior art and provide an airborne Hall signal processing system suitable for long-distance, high-interference environments. This system solves problems such as the original Hall signal being easily submerged by noise, signal distortion caused by common-mode interference in long-distance transmission loops, high-frequency coupling crosstalk of power lines intruding into the signal path, and signal edge jitter and glitches causing false triggering of back-end circuits. It provides high-fidelity signal support for stable commutation control of airborne motors.

[0006] The technical solution provided by this invention is as follows: An airborne Hall signal processing system suitable for long-distance, high-interference environments includes, in sequence, a surge protection unit, an opto-isolation unit, a low-pass filter unit, a Schmitt trigger shaping unit, and a push-pull drive unit along the Hall signal transmission direction. The surge protection unit is used to discharge lightning surge energy and provide overvoltage clamping protection for the input three-phase Hall signals HA, HB, and HC. It consists of a unidirectional TVS tube connected in parallel between the signal input terminal and the chassis ground. The cathode of the unidirectional TVS tube is connected to the signal input terminal, and the anode is connected to the chassis ground. An opto-isolation unit is used to implement electrical isolation between the preceding and following circuits. Preferably, the opto-isolation unit consists of high-frequency bypass capacitors C1-C3, a high-speed optocoupler U1, and its peripheral current-limiting resistors R1-R3 and pull-up resistors R4-R6. The three-phase Hall signals HA, HB, and HC are connected to the cathodes of the corresponding channels of the optocoupler U1 after passing through a surge protection unit, and high-frequency bypass capacitors C1-C3 are connected in parallel between the signal lines of the three-phase Hall signals HA, HB, and HC and the signal line GND. The anodes of each channel of the optocoupler U1 are connected to the power supply through current-limiting resistors R1, R2, and R3, respectively. The collectors of the output terminals of the optocoupler U1 are connected to the isolation power supply through pull-up resistors R4, R5, and R6, respectively, and the emitters are connected to the isolation ground GNDH, outputting three-phase isolation signals HAA, HBB, and HCC. A low-pass filter unit is used to filter out high-frequency crosstalk noise carried in the three-phase Hall signals output by the opto-isolation unit. Preferably, the low-pass filter unit is composed of three first-order RC low-pass filter networks. In each filter network, one end of the filter resistors R7, R8, and R9 is connected to the three-phase isolation signals HAA, HBB, and HCC output by the opto-isolation unit, respectively, and the other end outputs the filtered signals HAR, HBR, and HCR, and is connected to one end of the corresponding filter capacitors C4, C5, and C6. The other ends of the filter capacitors C4, C5, and C6 are connected to the isolation ground GNDH, forming three independent RC low-pass filter channels. The Schmitt trigger is used to hysteresis-shape the three-phase Hall signal output from the low-pass filter unit. Preferably, the Schmitt trigger integrates six independent Schmitt inverters, with each pair of Schmitt inverters forming a group to process one-phase Hall signal. The signals HAR, HBR, and HCR output from the low-pass filter unit are respectively connected to the input terminals of the first-stage Schmitt inverters in the corresponding group of U2. When the input signal level exceeds the Schmitt hysteresis window, the output of the first-stage Schmitt inverter immediately flips and locks, filtering out jitter and glitches at the signal edges. The first-stage output is connected to the input terminal of the second-stage Schmitt inverter in the same group. After being inverted and shaped again, it outputs clean pulse signals HAO, HBO, and HCO that are in phase with the original input signal, have steep edges, and are free from interference. A push-pull drive unit is used to amplify the power of the three-phase Hall signals output by the Schmitt trigger shaping unit and to suppress transient interference using device characteristics. Preferably, the push-pull drive unit includes three sets of push-pull drive sub-units, each set consisting of a dual NPN transistor array U3 and a pull-up resistor R10. In each set of push-pull drive sub-units, the HAO, HBO, and HCO signals output by the Schmitt trigger shaping unit are respectively connected to the base of the upper transistor in the dual NPN transistor array U3. The collector of the upper transistor is connected to the isolation power supply through the pull-up resistor R10 and is also connected to the base of the lower transistor. The emitters of the upper and lower transistors are connected to the isolation ground GNDH. The collector of the lower transistor serves as the output terminals HA1, HB1, and HC1 of the push-pull drive unit.

[0007] This invention employs a collaborative anti-interference architecture combining surge protection and high-speed optocoupler isolation. At the signal input, a TVS diode connected to the chassis ground discharges lightning surge energy, preventing surge current from flowing through the signal ground loop and causing ground potential rise. An electrical isolation link is constructed using high-speed optocouplers, cutting off long-line transmission ground loops at their source to suppress common-mode interference. The low-latency characteristics of the high-speed optocouplers ensure lossless signal transmission at the edges. These two elements form a collaborative protection-isolation architecture, simultaneously resisting multiple superimposed interferences from lightning surges, ground loop common-mode interference, and high-frequency coupling crosstalk from power lines, significantly improving the system's survivability and signal integrity in airborne, long-distance, high-interference environments.

[0008] This invention employs a cascaded conditioning structure combining frequency domain filtering and time domain shaping. A pre-amplified RC low-pass filter precisely removes kHz-level broadband noise generated by power line coupling, achieving frequency domain noise reduction. A post-amplified Schmitt trigger utilizes hysteresis to eliminate signal edge jitter and glitches, achieving time domain shaping. By connecting two inverters in series, the output remains in phase while leveraging the advantages of hysteresis shaping, completely solving the problem of false triggering of back-end circuits caused by signal distortion and edge jitter during long-distance transmission.

[0009] This invention employs a drive enhancement and intrinsic filtering design based on a dual NPN topology. A two-stage series push-pull power amplifier topology is constructed using dual NPN transistors, leveraging the high-current output characteristics of the transistors to enhance the terminal signal drive capacity. The two-stage symmetrical series architecture ensures distortion-free signal phase transmission. The inherent switching delay characteristics of the transistors are innovatively exploited to adaptively filter out high-frequency narrow spikes and glitches at the hardware level. As the terminal component of the signal processing system, it realizes the conversion of weak acquisition signals into highly reliable drive commands, strengthening the ability to suppress transient interference.

[0010] The airborne Hall signal processing system suitable for long-distance, high-interference environments provided by the present invention has the following advantages: (1) Significantly enhanced anti-interference and protection capabilities. The surge energy from lightning strikes is directly discharged to the chassis ground through a TVS diode, avoiding interference with the signal ground loop; at the same time, electrical isolation is achieved using a high-speed optocoupler, physically cutting off the ground loop interference path. This synergistic anti-interference architecture of surge protection and high-speed optocoupler isolation can simultaneously cope with surge impact, common-mode interference and high-frequency crosstalk, ensuring complete signal transmission in strong interference environments.

[0011] (2) Significantly improved signal quality and elimination of false triggering. A cascaded processing strategy of filtering followed by shaping is adopted. Low-frequency noise is effectively attenuated by the RC circuit, while edge jitter and glitches are completely eliminated by the Schmitt trigger. The overall conditioning link maintains output phase consistency while purifying the signal, solving the problem of false triggering of the back-end circuit caused by waveform distortion in long-distance transmission.

[0012] (3) Balancing driving capability and interference suppression. The push-pull output stage, based on dual NPN transistors, provides sufficient current driving capability to meet the terminal load requirements; at the same time, it cleverly utilizes the inherent switching delay of the transistors to form a time filtering window, which can filter out narrow pulse glitches without additional components, achieving highly reliable command conversion and adaptive suppression of transient interference. Attached Figure Description

[0013] Figure 1 Block diagram of an airborne Hall signal processing system suitable for long-distance, high-interference environments; Figure 2 This is a block diagram of the opto-isolation unit. Figure 3 This is a block diagram of a low-pass filter unit. Figure 4 This is a block diagram of the Schmidt shaping unit principle; Figure 5 This is a block diagram of the push-pull drive unit. Detailed Implementation

[0014] The features and advantages of the present invention will become clearer and more apparent from the following detailed description.

[0015] The term “exemplary” as used herein means “serving as an example, embodiment, or illustration.” Any embodiment illustrated herein as “exemplary” is not necessarily to be construed as superior to or better than other embodiments.

[0016] like Figure 1 As shown, the present invention provides an airborne Hall signal processing system suitable for long-distance, high-interference environments, comprising, in sequence along the Hall signal transmission direction, five parts: a surge protection unit, an opto-isolation unit, a low-pass filter unit, a Schmitt trigger shaping unit, and a push-pull drive unit.

[0017] The surge protection unit is used to discharge surge energy and clamp overvoltage for the input three-phase Hall signals HA, HB, and HC. It consists of a unidirectional TVS diode connected in parallel between the signal input terminal and the chassis ground. The cathode of the unidirectional TVS diode is connected to the signal input terminal, and the anode is connected to the chassis ground. The breakdown voltage parameter of the unidirectional TVS diode is matched and set according to the amplitude range of the output signal of the Hall sensor. When the airborne equipment encounters lightning surge interference, the unidirectional TVS diode quickly conducts with a picosecond response speed, directly discharging the surge energy to the chassis ground, while clamping the input signal voltage within a safe operating range to prevent high-voltage spike pulses from intruding into subsequent circuits and preventing damage to subsequent functional units due to overvoltage.

[0018] In a preferred embodiment, the Hall sensor is powered by 15V DC and its output signal amplitude ranges from 0 to 15V. Therefore, when a unidirectional TVS diode is selected as the protection device, the reverse turn-off voltage of the unidirectional TVS diode can be 16V, which is slightly higher than the maximum amplitude of the Hall sensor output signal. This ensures that the sensor is always in the cut-off state when it is working normally and will not affect the original signal transmission, thus achieving a balance between protection function and signal fidelity.

[0019] like Figure 2 As shown, the opto-isolation unit consists of high-frequency bypass capacitors C1~C3, a high-speed optocoupler U1, and its peripheral current-limiting resistors R1~R3 ​​and pull-up resistors R4~R6. The three-phase Hall signals HA, HB, and HC are connected to the cathodes of the corresponding channels of the optocoupler U1 after passing through the surge protection unit. High-frequency bypass capacitors C1~C3 are connected in parallel between the signal lines of the three-phase Hall signals HA, HB, and HC and the signal line GND. The anodes of each channel of the optocoupler U1 are connected to the +15V power supply terminal through current-limiting resistors R1 / R2 / R3. The collectors of the output terminals of the optocoupler U1 are connected to the isolation power supply +12VH through pull-up resistors R4 / R5 / R6, and the emitters are connected to the isolation ground GNDH, outputting three-phase isolation signals HAA, HBB, and HCC to achieve electrical isolation between the preceding and following circuits.

[0020] In a preferred embodiment, the high-speed optocoupler U1 is driven by either a low-level or high-level active mode. When the low-level active mode is used: when the Hall sensor outputs a low-level signal (0V), the corresponding channel's LED is forward-biased, driving the phototransistor into the conducting state, and the output terminal is pulled low; when the Hall sensor outputs a high-level signal (15V), the LED is reverse-biased and cut off, the phototransistor is synchronously turned off, and the output terminal is pulled high through a pull-up resistor.

[0021] The high-frequency bypass capacitors C1 to C3 are selected based on the principle of providing a low-impedance discharge path for high-frequency crosstalk noise without affecting the transmission of the valid Hall signal. In this embodiment, the high-frequency bypass capacitors C1 to C3 are 1nF.

[0022] The values ​​of the current-limiting resistors R1 to R3 must ensure that the input current of each channel's LED meets the conduction requirements when driven at a low level. In this embodiment, the typical forward voltage drop V of the LED is determined based on the 15V power supply on the optocoupler input side and the conduction characteristics of the LED. F Approximately 1.8V, from the formula R=(V CC -V F ) / I F Calculations show that the current-limiting resistors R1~R3 ​​should have a value of 1. The input current can be stabilized within the recommended range of 12~20mA to ensure reliable conduction of the LED. In the formula, V... CC The DC power supply voltage for the Hall sensor, I F R is the conduction current of the LED, and R is the resistance of the current-limiting resistor.

[0023] The values ​​of pull-up resistors R4 to R6 need to be matched and set in conjunction with the optocoupler's current transfer ratio (CTR) and the maximum sinking current capability of the output stage. Based on a high-speed optocoupler current transfer ratio (CTR) ≥ 15%, a channel peak output current of 16mA, and an output current I... O =I F ×CTR=2.4mA, pull-up resistors R4~R6 are 10 It can fully saturate the phototransistor, ensuring stable and reliable three-phase output levels.

[0024] like Figure 3As shown, the low-pass filter unit is used to filter out high-frequency crosstalk noise carried in the three-phase Hall signals output by the opto-isolation unit, and consists of three first-order RC low-pass filter networks. In each filter network, one end of the filter resistors R7 / R8 / R9 is connected to the three-phase isolation signals HAA / HBB / HCC output by the opto-isolation unit, respectively, and the other end outputs the filtered signals HAR / HBR / HCR and is connected to one end of the corresponding filter capacitors C4 / C5 / C6; the other end of the filter capacitors C4 / C5 / C6 is connected to the isolation ground GNDH, forming three independent RC low-pass filter channels.

[0025] The cutoff frequency of each filter is given by the formula f. c =1 / (2π×R×C) is used to determine the value of R, where R is the resistance of the resistors (R7 / R8 / R9) in each filter, and C is the farad value of the filter capacitors (C4 / C5 / C6) in each filter. The values ​​of R and C must simultaneously satisfy the following requirements: effectively filtering out high-frequency crosstalk noise introduced by distributed capacitance coupling and electromagnetic induction when power lines and signal lines are laid in the same bundle; and completely preserving the effective frequency components of the three-phase Hall signal to avoid attenuation or phase distortion of normal signals. In this embodiment, the values ​​of R7 / R8 / R9 are all 1.8. C4 / C5 / C6 all have values ​​of 1nF. Substituting these values ​​into the parameters of this embodiment, the cutoff frequency f is calculated. c At approximately 88.4kHz, which is higher than the effective operating frequency range of Hall signals, the effective signal can be transmitted without distortion while suppressing high-frequency interference.

[0026] like Figure 4 As shown, the Schmitt trigger shaping unit is used to perform hysteresis shaping on the three-phase Hall signal output by the low-pass filter unit, and is composed of Schmitt trigger U2.

[0027] In a preferred embodiment, the selected Schmitt trigger integrates six independent Schmitt inverters. Every two Schmitt inverters form a group for processing a single-phase Hall signal: the signals HAR, HBR, and HCR output from the low-pass filter unit are respectively connected to the input terminals of the first-stage Schmitt inverter in the corresponding group of U2; when the input signal level exceeds the Schmitt hysteresis window, the output of the first-stage Schmitt inverter immediately flips and locks, filtering out jitter and glitches at the signal edges; the first-stage output is connected to the input terminal of the second-stage Schmitt inverter in the same group, and after being inverted and shaped again, it outputs clean pulse signals HAO, HBO, and HCO that are in phase with the original input signal, have steep edges, and are free from interference.

[0028] like Figure 5 As shown, the push-pull drive unit is used to amplify the power of the three-phase Hall signal output from the Schmitt trigger shaping unit, enhancing the signal drive capacity, and simultaneously utilizing device characteristics to suppress transient interference. Figure 5Taking the A-phase (or B-phase, C-phase) signal channel shown as an example, this unit is composed of a dual NPN transistor array U3 and a pull-up resistor R10.

[0029] The HAO (HBO or HCO) signal output by the Schmitt trigger shaping unit is connected to the base of the upper transistor in the dual NPN transistor array U3. The collector of the upper transistor is connected to the isolation power supply +12VH through the pull-up resistor R10, and is also connected to the base of the lower transistor. The emitters of the upper and lower transistors are connected to the isolation ground GNDH. The collector of the lower transistor serves as the output terminal HA1 (HB1 or HC1) of the push-pull drive unit.

[0030] In a preferred embodiment, the typical turn-on and turn-off delay of the selected dual NPN transistor array is approximately tens of nanoseconds, and the continuous collector current of a single transistor can reach 600mA. The value of the pull-up resistor R10 at the collector of the upper transistor must ensure reliable saturation conduction of the transistor under the selected isolated power supply conditions; in this embodiment, the value is 3. .

[0031] When the signal HAO (HBO or HCO) is high, the base of the upper transistor is effectively driven and saturated, and its collector potential is pulled low to GNDH. The base of the lower transistor is then at a low level and cut off, and HA1 outputs a high level. When the signal HAO (HBO or HCO) is low, the upper transistor is cut off, and its collector potential is pulled high to +12VH through the pull-up resistor R10, which effectively drives the base of the lower transistor and saturates, and HA1 (HB1 or HC1) outputs a low level.

[0032] By alternating the conduction of the upper and lower transistors, this unit achieves inverted signal output and power amplification, significantly improving the signal's drive capability. At the same time, this structure can utilize the inherent switching delay of the transistors to suppress narrow pulse spike interference without additional components, thus enhancing the system's transient immunity.

[0033] The present invention has been described in detail above with reference to specific embodiments and exemplary examples; however, these descriptions should not be construed as limiting the present invention. Those skilled in the art will understand that various equivalent substitutions, modifications, or improvements can be made to the technical solutions and embodiments of the present invention without departing from the spirit and scope of the invention, and all such modifications and improvements fall within the scope of the present invention. The scope of protection of the present invention is defined by the appended claims.

[0034] The contents not described in detail in this specification are common knowledge to those skilled in the art.

Claims

1. An airborne Hall signal processing system suitable for long-distance, high-interference environments, characterized in that, It includes, in sequence, a surge protection unit along the Hall signal transmission direction, an opto-isolation unit, a low-pass filter unit, a Schmitt trigger shaping unit, and a push-pull drive unit; The surge protection unit is used to discharge lightning surge energy and provide overvoltage clamping protection for the input three-phase Hall signals HA, HB, and HC. It consists of a unidirectional TVS tube connected in parallel between the signal input terminal and the chassis ground. The cathode of the unidirectional TVS tube is connected to the signal input terminal, and the anode is connected to the chassis ground. The opto-isolation unit consists of high-frequency bypass capacitors C1-C3, a high-speed optocoupler U1, and its peripheral current-limiting resistors R1-R3 and pull-up resistors R4-R6. The three-phase Hall signals HA, HB, and HC are connected to the cathodes of the corresponding channels of the optocoupler U1 after passing through the surge protection unit. The high-frequency bypass capacitors C1-C3 are connected in parallel between the signal lines of the three-phase Hall signals HA, HB, and HC and the signal line GND. The anodes of each channel of the optocoupler U1 are connected to the power supply through current-limiting resistors R1, R2, and R3. The collectors of the output terminals of the optocoupler U1 are connected to the isolation power supply through pull-up resistors R4, R5, and R6, and the emitters are connected to the isolation ground GNDH. The three-phase isolation signals HAA, HBB, and HCC are output to implement electrical isolation between the preceding and following circuits. The low-pass filter unit is used to filter out high-frequency crosstalk noise carried in the three-phase Hall signal output by the opto-isolation unit; The Schmitt trigger shaping unit is used to perform hysteresis shaping on the three-phase Hall signal output from the low-pass filter unit. The push-pull drive unit is used to amplify the power of the three-phase Hall signal output by the Schmitt trigger shaping unit and to suppress transient interference using the device characteristics.

2. The airborne Hall signal processing system suitable for long-distance, high-interference environments according to claim 1, characterized in that, The reverse turn-off voltage of the unidirectional TVS diode in the surge protection unit is higher than the maximum amplitude of the Hall sensor output signal.

3. The airborne Hall signal processing system suitable for long-distance, high-interference environments according to claim 1, characterized in that, The high-frequency bypass capacitors C1~C3 in the opto-isolation unit are selected based on the following criteria: to provide a low-impedance discharge path for high-frequency crosstalk noise without affecting the transmission of the effective Hall signal. The values ​​of the current-limiting resistors R1 to R3 must ensure that the input current of each channel's LED meets the conduction requirement when driven at a low level; this is determined by the formula R = (V CC -V F ) / I F Calculate the resistance value of the current-limiting resistor, where V is in the formula. CC The DC power supply voltage for the Hall sensor, I F This is the on-state current of the LED; The values ​​of pull-up resistors R4 to R6 are determined by matching the current transfer ratio of the optocoupler and the maximum sinking current capability of the output stage.

4. The airborne Hall signal processing system suitable for long-distance, high-interference environments according to claim 1, characterized in that, The low-pass filter unit consists of three first-order RC low-pass filter networks. In each filter network, one end of the filter resistors R7, R8, and R9 is connected to the three-phase isolation signals HAA, HBB, and HCC output by the opto-isolation unit, respectively, and the other end outputs the filtered signals HAR, HBR, and HCR, and is connected to one end of the corresponding filter capacitors C4, C5, and C6. The other ends of the filter capacitors C4, C5, and C6 are connected to the isolation ground GNDH, forming three independent RC low-pass filter channels.

5. The airborne Hall signal processing system suitable for long-distance, high-interference environments according to claim 4, characterized in that, The cutoff frequency of each filter in the low-pass filter unit is given by formula f. c =1 / (2π×R×C) is used to determine the value of the resistor in each filter and the value of the filter capacitor in each filter. The values ​​of R and C must simultaneously meet the following requirements: filter out high-frequency crosstalk noise introduced by distributed capacitance coupling and electromagnetic induction when power lines and signal lines are laid in the same bundle; and fully retain the effective frequency components of the three-phase Hall signal to avoid attenuation or phase distortion of normal signals.

6. The airborne Hall signal processing system suitable for long-distance, high-interference environments according to claim 4, characterized in that, The Schmitt trigger integrates six independent Schmitt inverters, with each pair of Schmitt inverters forming a group to process a single-phase Hall signal. The signals HAR, HBR, and HCR output from the low-pass filter unit are respectively connected to the input terminals of the first-stage Schmitt inverters in the corresponding group of U2. When the input signal level exceeds the Schmitt hysteresis window, the output of the first-stage Schmitt inverter immediately flips and locks, filtering out jitter and glitches at the signal edges. The first-stage output is connected to the input terminal of the second-stage Schmitt inverter in the same group. After being inverted and shaped again, it outputs clean pulse signals HAO, HBO, and HCO that are in phase with the original input signal, have steep edges, and are free from interference.

7. The airborne Hall signal processing system suitable for long-distance, high-interference environments according to claim 6, characterized in that, The push-pull drive unit includes three sets of push-pull drive sub-units. Each set of push-pull drive sub-units consists of a dual NPN transistor array U3 and a pull-up resistor R10. In each set of push-pull drive sub-units, the HAO, HBO, and HCO signals output by the Schmitt trigger shaping unit are respectively connected to the base of the upper transistor in the dual NPN transistor array U3. The collector of the upper transistor is connected to the isolation power supply through the pull-up resistor R10 and is also connected to the base of the lower transistor. The emitters of the upper and lower transistors are connected to the isolation ground GNDH. The collector of the lower transistor serves as the output terminals HA1, HB1, and HC1 of the push-pull drive unit.

8. The airborne Hall signal processing system suitable for long-distance, high-interference environments according to claim 7, characterized in that, When signals HAO, HBO, or HCO are high, the base of the upper transistor is effectively driven and saturated, and its collector potential is pulled low to GNDH. The base of the lower transistor is then at a low level and cut off, and HA1 outputs a high level. When signals HAO, HBO, or HCO are low, the upper transistor is cut off, and its collector potential is pulled high to +12VH through the pull-up resistor R10, which effectively drives the base of the lower transistor and saturates, and HA1, HB1, or HC1 outputs a low level.

Images