A near space sounding balloon with a rope cutter and a data processing splicing method

Abstract

The application discloses a near-space sounding instrument with a rope cutter and a data processing splicing method, and relates to the technical field of sounding instruments. The near-space sounding instrument comprises a parachute, a parachute rope, a sounding instrument and a rope cutter. The parachute is connected with the sounding instrument through the parachute rope. The sounding instrument comprises a shell, a lithium battery, a digital transmitter, an air pressure sensor, a data acquisition circuit, a high dynamic satellite navigation positioning module, a wireless remote control module, a mechanical switch and a temperature sensor which are arranged in the shell. The rope cutter is arranged in a cavity in the shell. The data processing splicing method comprises data analysis, quality control, correction and splicing processes. The near-space sounding data from the ground to a height of 60km can be generated. The sounding instrument can be quickly landed on the ground, the data acquisition rate is improved, and the data accuracy, consistency and integrity are ensured.

Description

Technical Field

[0001] This invention belongs to the field of instrumentation technology, specifically relating to a near-space radiosonde with a built-in rope cutter and a data processing and splicing method. Background Technology

[0002] Near space refers to the airspace between 20 and 100 km, which is between the flight altitudes of traditional aircraft and spacecraft. It is characterized by thin air and a stable environment. Using meteorological rockets for detection is the only in-situ measurement method at this altitude.

[0003] Due to the extremely low atmospheric density at this altitude, the parachute area must be increased to enhance drag and ensure successful parachute deployment. The descent speed during parachute-sonde separation is approximately 200 m / s. This rapid descent causes the sonometer to cone-shaped at the parachute's lower end, easily leading to abnormal ground-to-ground data communication and data packet loss. Consequently, the data acquisition rate of related sonometers both domestically and internationally is only around 80-90%, severely impacting data quality. Furthermore, as the sonometer descends, atmospheric density increases, the descent speed slows, and the loiter time reaches 3-4 hours. If crosswinds are present, the impact area is large, affecting not only the normal flight of other aircraft but also potentially causing it to drift out of the planned airspace. Due to the parachute's descent speed, to improve the timeliness of detection operations, a sounding balloon carrying a BeiDou satellite navigation sonometer is typically used to assist in measuring atmospheric parameters from the ground to an altitude of approximately 20 km. This results in discontinuities in the two sets of data measurements near this altitude. Summary of the Invention

[0004] The purpose of this invention is to provide a near-space radiosonde with a built-in rope cutter and a data processing and splicing method, which aims to reduce problems such as long parachute-radiosonde loiter time, large landing area, and data packet loss during downlink, so as to achieve rapid landing of the radiosonde and significantly improve the data acquisition rate, while ensuring the accuracy, consistency and integrity of the detection data from the ground to a near-space altitude of 60km.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0006] A near-space radiosonde with a built-in rope cutter includes a parachute, parachute lines, and a radiosonde, wherein the parachute is connected to the radiosonde via the parachute lines.

[0007] The radiosonde includes a housing and, installed within the housing, a lithium battery, a digital transmitter, a barometric pressure sensor, a data acquisition circuit, a high-dynamic satellite navigation and positioning module, a wireless remote control module, a mechanical switch, and a temperature sensor. The lithium battery powers the entire radiosonde. The high-dynamic satellite navigation and positioning module, the barometric pressure sensor, and the temperature sensor are respectively connected to the data acquisition circuit. The data acquisition circuit is connected to the digital transmitter. The digital transmitter is connected to a ground-based satellite navigation radiosonde receiver via a ground-to-ground antenna. The wireless remote control module is signal-connected to both the wireless remote control device and the data acquisition circuit.

[0008] It also includes a rope cutter. The housing has a threading hole through which the paracord passes and connects to the radiosonde. A cavity communicating with the threading hole is provided on one side of the threading hole. The rope cutter is installed in the cavity. The rope cutter includes a shearing pin, a pyrotechnic gas generating device, and a cutter. The cutter is fixed in the cavity by the shearing pin. The pyrotechnic gas generating device is fixed on the inner wall of the cavity and located between the back force-bearing surface of the cutter and the bottom of the cavity. The pyrotechnic gas generating device contains combustible gas and is connected to a data acquisition circuit. When the radiosonde falls to a predetermined height or exceeds the landing area, the radiosonde issues a rope-cutting command. The data acquisition circuit outputs an ignition current, and the pyrotechnic gas generating device releases combustible gas, generating a thrust in the cavity, which acts on the back force-bearing surface of the cutter.

[0009] As a preferred technical solution of the present invention: the wireless remote control module includes a wireless data transmission module and a controllable voltage regulator. The wireless data transmission module is connected to the wireless remote control device and the data acquisition circuit respectively. The controllable voltage regulator is connected to the lithium battery. The wireless data transmission module receives the ground equipment remote control command issued by the wireless remote control device, controls the voltage regulator to start and stop, realizes the control of the lithium battery switch, and at the same time receives the command to modify the radiosonde frequency fed back by the data acquisition circuit.

[0010] As a preferred technical solution of the present invention: the pressure sensor adopts a silicon piezoresistive pressure sensor, which transmits the collected pressure signal to the data acquisition circuit.

[0011] As a preferred technical solution of the present invention: the temperature sensor is composed of two bead-shaped thermistors, and the collected ambient temperature signal is transmitted to the data acquisition circuit through a conversion circuit.

[0012] As a preferred technical solution of the present invention: the high dynamic satellite navigation and positioning module includes a satellite receiving antenna and a dual-system satellite positioning receiver. The satellite receiving antenna is signal-connected to the dual-system satellite positioning receiver. The satellite receiving antenna transmits the received BeiDou satellite radio frequency signals to the dual-system satellite positioning receiver. The dual-system satellite positioning receiver is connected to a data acquisition circuit.

[0013] As a preferred technical solution of the present invention: the data acquisition circuit adopts 5Hz high-frequency sampling to collect and compress the information from the barometric pressure sensor, temperature sensor, lithium battery, and radiosonde, and transmit it to the digital transmitter.

[0014] As a preferred technical solution of the present invention: the digital transmitter includes a wireless transmission chip and a linear power amplifier. The wireless transmission chip is connected to the data acquisition circuit, modulates and outputs the detection data of the radiosonde, amplifies it after being amplified by the linear power amplifier, and then transmits it to the ground satellite navigation radiosonde receiver through the ground antenna using a data combination delay repetition transmission mechanism.

[0015] As a preferred embodiment of the present invention, the interior of the shell is filled with thermal insulation material.

[0016] The data processing and splicing method includes the following steps:

[0017] S1. Determine if the radiosonde has descended to an altitude of 18km. If H n If the distance is ≥18km, then continue the evaluation. If H n If the altitude is ≤18km, then extract the detection data at altitudes of 18 to 60km;

[0018] S2, Analysis includes temperature T n air pressure P n Radiosonde location data lat n lon n H n 3D velocity data v from the radiosonde x v y v z If the temperature sensor data T n1 T n2 If both are normal, the average of the two values ​​is taken as the actual measurement value; otherwise, the temperature sensor measurement value with the lower value is taken as the actual measurement value, based on the radiosonde's axial velocity v. z Data is used to determine whether the radiosonde landed normally. If the v value is above 60km at various altitudes... z If all exceed 200m / s, the detection is considered a failure and data processing is terminated.

[0019] S3. If step S2 is normal, then perform quality control on the altitude data from 18 to 60 km.

[0020] S4. The three-dimensional velocity data v from the radiosonde. x v y v z Spectral analysis was performed to determine the oscillation frequency range of the radiosonde, and the three-dimensional velocity data v was analyzed. x v y v z Perform smoothing and filtering;

[0021] S5. Using polynomial fitting method based on three-dimensional velocity data v x v y v z Calculate three-dimensional acceleration data a x a y a z ;

[0022] S6. Using three-dimensional acceleration data a x a y a z Substituting the following wind field correction formula, for wind speed u s v s Make corrections:

[0023] (1);

[0024] (2);

[0025] S7. Based on the corrected speed information, substitute it into the wind speed and direction calculation formulas to synthesize the horizontal wind speed V and wind direction D:

[0026] (3);

[0027] (4);

[0028] S8. Based on the temperature sensor structure design, solve the optimized temperature correction equation given by the World Meteorological Organization to obtain the actual atmospheric temperature detection value T. ∞ :

[0029] (5);

[0030] Among them, T f For measuring temperature values ​​using a thermistor, For pneumatic heating correction, r is the temperature recovery coefficient of the airflow over the thermistor surface, and v r C represents the relative velocity between the airflow and the thermistor. p The specific pressure heat capacity of air is taken as 1004 J / (kg·K). For the lag effect correction term, m T C is the heat capacity of the thermistor, A is the surface area of ​​the thermistor, and h is the surface area of ​​the thermistor. cs The coefficient of convective heat exchange between the thermistor surface and the air. The rate of temperature change of the thermistor over time is taken as 0.0028℃; For the correction term of solar radiation emitted from the ground and clouds, A m ρ is the effective area of ​​the thermistor affected by solar radiation reflected from the ground and clouds. m α is the combined reflectance coefficient of the ground and clouds.s Let J be the absorptivity of the thermistor to solar radiation, and J be the solar constant, which is 1367 J / (s·m2). W is the correction term for the thermal loss of the measurement circuit. f To measure the heat generated by the Joule effect of electric current;

[0031] S9. Using the air pressure at an altitude of 20km as the initial value P0, based on the detection altitude H... n and the corrected temperature measurement value T ∞ Calculate the air pressure value P at each altitude using the static pressure formula:

[0032] (6);

[0033] Where H is the potential height at the desired altitude, H0 is the initial potential height (taken as 20000 m), and M is the average atmospheric molecular weight at altitude H (g). H Let H be the gravitational acceleration at height H, and R be the universal gas constant, taken as 8.314 J / (mol·K).

[0034] S10. Based on the air pressure value P and temperature detection value T at each altitude. ∞ Calculate the air density ρ at each altitude using the following formula:

[0035] (7);

[0036] S11. Iteratively calculate the temperature value, compare the temperature detection values ​​of two adjacent iterations, if the maximum difference is less than 0.01℃, stop the iteration, obtain the final temperature, air pressure, atmospheric density, and wind field measurement values ​​and proceed to step S12; otherwise, bring the temperature, air pressure, and density values ​​back into step S8 for iterative calculation.

[0037] S12. Synchronize temperature, air pressure, density, wind speed, and wind direction measurement data at the same time.

[0038] S13. Read data from the ground to a height of 20km using a sounding balloon;

[0039] S14. Compare the temperature difference between the weather balloon data and the near-space radiosonde data in the overlapping altitude segment. Take the altitude with the smallest difference between 18km and 20km as the splicing altitude. Take the near-space radiosonde data for 20 seconds above the splicing altitude and the weather balloon data for 20 seconds below the splicing altitude. Use polynomial fitting to smoothly connect the two data segments. Take the air pressure at the splicing point as P0 and recalculate the upward altitude to 60km according to the method in step S9. Calculate the atmospheric density according to the method in step S10.

[0040] S15. Store the data before and after processing into the database according to the prescribed format;

[0041] S16. Display the processed and spliced ​​data;

[0042] S17. Output data according to requirements.

[0043] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0044] 1. Short detection time and high efficiency:

[0045] The time from parachute deployment to descent to an altitude of approximately 18km is within 30 minutes, which is significantly shorter than the previous 3 to 4 hours, thus avoiding prolonged airspace occupation and preventing flight safety accidents.

[0046] 2. High data acquisition rate, high data accuracy, consistency, and completeness:

[0047] The ground-based antenna employs a dipole antenna deformation technique, avoiding data packet loss issues caused by the radiosonde flying too high overhead or too far. Through high-frequency sampling, data combination, and delayed retransmission techniques, the ground-based satellite navigation radiosonde receiver achieves a data acquisition rate exceeding 99.9% for the radiosonde's downlink data, which is more than 5% higher than that of mainstream domestic rocket radiosondes. Simultaneously, scientifically sound and feasible data processing and stitching methods are used to improve the accuracy, consistency, and completeness of the probe data.

[0048] 3. The radiosonde has strong environmental adaptability:

[0049] The layout of all components takes into full account the impact of environmental changes. The radiosonde can operate normally at high temperatures of +60℃ and low temperatures of -40℃. The battery is a low-temperature rechargeable lithium battery, which fully meets the low-temperature adaptability requirements of near-space.

[0050] 4. The radiosonde has high reliability:

[0051] BeiDou offers high positioning accuracy, fast satellite acquisition speed, and short reacquisition time. Its navigation and positioning module receiver is small in size, low in power consumption, and highly resistant to shock. Multiple ground tests and high-altitude sounding experiments have demonstrated that the radiosonde provides accurate data acquisition, has a high data transmission rate, and the shearer functions normally, meeting the design objectives.

[0052] 5. High-quality temperature detection data:

[0053] The selection of radiosonde components, structural design, and data processing fully consider the influence of the working environment and atmospheric environment. It adopts dual thermistors, selects lower measurement values ​​for data processing, and uses a lead wire structure and resistance wire with a diameter of less than 0.05mm with silver plating to make a radiation protection layer. This can effectively reduce solar shortwave radiation and environmental longwave radiation, while reducing radiation to the environment and heat conduction from the bracket to the thermistor. It can ignore solar radiation, environmental longwave radiation, radiation from the sensor to the environment, and heat conduction from the bracket to the thermistor. Attached Figure Description

[0054] Figure 1 This is a schematic diagram of the detection process of the radiosonde in this invention;

[0055] Figure 2 This is a block diagram of the radiosonde components in this invention;

[0056] Figure 3 This is a schematic diagram of the radiosonde structure in this invention;

[0057] Figure 4 This is a schematic diagram of the shear structure in this invention;

[0058] Figure 5 This is a flowchart of the rope-cutting control method in this invention;

[0059] Figure 6 This is a flowchart of the data processing and splicing process in this invention;

[0060] Figure 7 This is a detection result from one instance in this invention.

[0061] List of reference numerals in the attached diagram:

[0062] 1. Parachute; 2. Parachute lines; 3. Radiosonde; 4. Lithium battery; 5. Digital transmitter; 6. Barometric pressure sensor; 7. Data acquisition circuit; 8. Rope cutter; 9. High dynamic satellite navigation and positioning module; 10. Housing; 11. Wireless remote control module; 12. Mechanical switch; 13. Temperature sensor; 14. Shear pin; 15. Cavity; 16. Pyrotechnic gas generator; 17. Cutter. Detailed Implementation

[0063] The present invention will be further illustrated below with reference to the accompanying drawings and specific embodiments. It should be understood that the following specific embodiments are for illustrative purposes only and are not intended to limit the scope of the invention.

[0064] like Figure 1-4 As shown, the present invention proposes a near-space radiosonde with a built-in rope cutter, which includes a parachute 1, parachute ropes 2 and a radiosonde 3. The parachute 1 is connected to the radiosonde 3 through the parachute ropes 2, and the radiosonde 3 is connected to a wireless remote control device and a ground satellite navigation radiosonde receiver.

[0065] The radiosonde 3 includes a housing 10 and a lithium battery 4, a digital transmitter 5, a barometric pressure sensor 6, a data acquisition circuit 7, a high-dynamic satellite navigation and positioning module 9, a wireless remote control module 11, a mechanical switch 12, and a temperature sensor 13 installed inside the housing 10. The lithium battery 4 powers the entire radiosonde 3. The high-dynamic satellite navigation and positioning module 9, the barometric pressure sensor 6, and the temperature sensor 13 are respectively connected to the data acquisition circuit 7. The data acquisition circuit 7 is connected to the digital transmitter 5. The digital transmitter 5 is connected to a ground satellite navigation radiosonde receiver through a ground-to-ground antenna. The wireless remote control module 11 is connected to both the wireless remote control device and the data acquisition circuit 7.

[0066] The wireless remote control module 11 includes a wireless data transmission module and a controllable voltage regulator. The wireless data transmission module is connected to the wireless remote control device and the data acquisition circuit 7 respectively. The controllable voltage regulator is connected to the lithium battery 4. The wireless data transmission module receives the ground equipment remote control command issued by the wireless remote control device, controls the voltage regulator to start and stop, and realizes the control of the lithium battery 4. At the same time, it receives the command from the data acquisition circuit 7 to modify the frequency of the radiosonde 3.

[0067] The pressure sensor 6 is a silicon piezoresistive pressure sensor that transmits the collected pressure signal to the data acquisition circuit 7.

[0068] The temperature sensor 13 consists of two beaded thermistors, which transmit the collected ambient temperature signal to the data acquisition circuit 7 through a conversion circuit.

[0069] The high-dynamic satellite navigation and positioning module 9 includes a satellite receiving antenna and a dual-system satellite positioning receiver. The satellite receiving antenna is signal-connected to the dual-system satellite positioning receiver. The satellite receiving antenna transmits the received BeiDou satellite radio frequency signals to the dual-system satellite positioning receiver. The dual-system satellite positioning receiver is connected to the data acquisition circuit 7.

[0070] The data acquisition circuit 7 uses 5Hz high-frequency sampling to compress and transmit the information collected from the barometric pressure sensor 6, temperature sensor 13, lithium battery 4, and radiosonde 3 to the digital transmitter 5.

[0071] The digital transmitter 5 includes a wireless transmission chip and a linear power amplifier. The wireless transmission chip is connected to the data acquisition circuit 7, modulates and outputs the detection data of the radiosonde 3, amplifies it after being amplified by the linear power amplifier, and then transmits it to the ground satellite navigation radiosonde receiver via the ground antenna using a data combination delay repetition transmission mechanism.

[0072] The interior of the shell 10 is filled with thermal insulation material.

[0073] It also includes a rope cutter 8. A threading hole is provided on the housing 10. The paracord 2 passes through the threading hole and is connected to the radiosonde 3. A cavity 15 communicating with the threading hole is provided on one side. The rope cutter 8 is installed in the cavity 15. The rope cutter 8 includes a shearing pin 14, a pyrotechnic gas generating device 16, and a cutter 17. The cutter 17 is fixed in the cavity 15 by the shearing pin 14. The pyrotechnic gas generating device 16 is fixed on the inner wall of the cavity 15 and is located between the back force-bearing surface of the cutter 17 and the bottom of the cavity 15. The pyrotechnic gas generating device 16 contains combustible gas. The pyrotechnic gas generating device 16 is connected to the data acquisition circuit 7. When the radiosonde 3 falls to a predetermined height or exceeds the fall area, the radiosonde 3 issues a rope-cutting command. The data acquisition circuit 7 outputs an ignition current, and the pyrotechnic gas generating device 16 releases combustible gas, generating a pushing force in the cavity 15, which acts on the back force-bearing surface of the cutter 17.

[0074] This application employs a meteorological rocket to launch a radiosonde at an altitude of approximately 70km. Under atmospheric drag, the parachute 1 deploys and decelerates the radiosonde 3 during its descent. During the descent of the radiosonde 3, parameters such as atmospheric temperature, air pressure, and the radiosonde 3's position are measured in an area from 60km to 20km. To improve the data reporting rate, high-resolution sampling and data combination delay repetitive transmission techniques are used to package the collected data. The data is then transmitted in real time to a ground-based satellite navigation radiosonde receiver via a digital transmitter 5. The receiver calculates and generates parameters such as temperature, air pressure, atmospheric density, wind direction, wind speed, and the radiosonde 3's latitude, longitude, and altitude.

[0075] To address the data transmission packet loss issues caused by the radiosonde 3 passing overhead and at long distances, the ground-pointing antenna of the digital transmitter 5 employs a dipole antenna deformation, resulting in a near-omnidirectional radiation direction. To resolve issues such as prolonged airspace occupation affecting the flight safety of other aircraft, a rope cutter module 8 is added. When the radiosonde 3 descends to an altitude of approximately 18km or exceeds the planned airspace, the cutter, based on the ambient air pressure, altitude, and latitude / longitude information provided by the radiosonde 3, cuts the parachute ropes 2 of parachute 1. This allows the radiosonde 3 to descend rapidly without the deceleration provided by parachute 1, while simultaneously, without the gravitational pull of the radiosonde 3, parachute 1 gradually deforms and lands quickly.

[0076] The specific implementation method of the radiosonde 3 is as follows:

[0077] Currently, domestic radiosondes have a data sampling rate of 1Hz or 2Hz and only transmit data once to the ground-based satellite navigation radiosonde receiver. During near-space environment exploration, considering that the radiosonde's violent swaying under the parachute can easily lead to abnormal or interrupted data communication with the ground, the data acquisition rate will significantly decrease. Therefore, this invention increases the data sampling frequency of the radiosonde 3 to 5Hz and employs a data combination delay retransmission mechanism. During the exploration process, the digital acquisition circuit 7 stores the measurement data 4 seconds before the current time T0, and packages the data from T0-2 and T0-4 seconds with the exploration data at time T0 for real-time transmission to improve the data acquisition rate of the ground-based satellite navigation radiosonde receiver.

[0078] In this application, the radiosonde 3 operates in the 400–406 MHz frequency band, with a data transmission frequency of 5 Hz. It utilizes the BeiDou satellite navigation and positioning system. Temperature and air pressure are directly measured by sensors, while wind direction and speed are calculated inversely based on the radiosonde 3's drifting and positioning information. The implementation of each component of the radiosonde 3 is as follows:

[0079] High Dynamic Satellite Navigation and Positioning Module 9:

[0080] This module consists of a satellite receiving antenna and a dual-system satellite positioning receiver. It receives satellite signals through the satellite guidance antenna, performs positioning calculations in the radio frequency section of the satellite guidance device, and outputs positioning information such as the position and velocity of the radiosonde 3 after the calculations are completed. The dual-system satellite positioning receiver uses BeiDou satellite positioning and can receive the BDS-B1 frequency point with an accuracy of 50ns per 1PPS. The receiving antenna is a GNSS airborne antenna that can receive BeiDou-2 B1 frequency signals. This module is installed on the upper part of the radiosonde 3, with the GNSS airborne antenna located below the shearer to ensure optimal satellite signal reception during the detection process. This module employs high-overload resistant hardware design and high-dynamic signal processing algorithms to ensure normal operation even under 40g acceleration, guaranteeing that the radiosonde 3 does not lose lock-on during the high-overload and high-speed flight conditions of the meteorological rocket launch phase.

[0081] Temperature sensor 13:

[0082] A dual-bead thermistor sensor is employed to achieve backup and complementarity during the detection process. The temperature sensor 13 bracket uses a lead wire structure and resistance wire with a diameter of less than 0.05mm, with a silver-plated radiation shielding layer. The dual temperature sensors 13 are arranged at the bottom of the radiosonde 3, parallel to the centerline, and at the same height. This ensures that the airflow passes through the temperature sensor 13 first during descent, while also eliminating the influence of the housing 10 or other components on the airflow to avoid measurement deviations and promote the consistency of the data collected by the temperature sensor 13.

[0083] Barometric pressure sensor 6:

[0084] A silicon piezoresistive sensor is used, with an integrated temperature sensor 13 for easy temperature compensation during air pressure measurement. The air pressure sensor 6 is located inside the housing 10 on the data acquisition circuit 7, and is externally insulated to reduce the impact of temperature changes. The data acquisition circuit 7 also generates heat to maintain the normal operating temperature.

[0085] Data acquisition circuit 7:

[0086] The data acquisition circuit 7 is installed in the middle of the radiosonde 3. Data acquisition and control primarily utilize a Cortex-M3 architecture processor with a maximum clock frequency of 24MHz, 128K Flash, and 32K SRAM. It includes two serial ports, three UART ports, one AD port, two SPI ports, and multiple timers. The serial ports are used for communication between the wireless receiving module and the satellite navigation and positioning module; the AD port is used to acquire battery voltage; the SPI port is used for communication between the barometric pressure sensor 6 and the transmitting module; the UART port is used for communication with the temperature sensor 13; and the timer ports are used to acquire the oscillation period of the temperature sensor 13. It can acquire data from one barometric pressure sensor 6, two temperature sensors 13, the lithium battery 4 voltage, and the navigation and positioning module. While meeting sensor resolution requirements, the data sampling frequency of the radiosonde 3 is set to 5Hz. By increasing the processor's clock frequency, the frequency measurement resolution is improved, enabling the processor to process one frame of measurement data within 0.2 seconds. The Cortex-M3 architecture processor has a larger memory capacity, facilitating the storage of high-frequency sampling data. After data acquisition is completed, the data is packaged according to the designed data protocol, output to digital transmitter 5, and then transmitted to the ground satellite navigation sounding receiver in real time.

[0087] Digital Transmitter 5:

[0088] Composed of a wireless transmitter chip and a linear power amplifier, it is installed in the upper part of the radiosonde 3 and connected to the data acquisition circuit 7. The MCU (microcontroller unit) controls the output power, transmission frequency, modulation mode, and other parameters of the transmitter chip, and serially sends the detection data to the transmitter chip. The transmitter chip modulates the data, amplifies it through a subsequent amplifier, and transmits it wirelessly through the antenna to the ground satellite navigation radiosonde receiver, achieving data transmission within a slant range of 200km.

[0089] Among them, the ground-to-ground antenna of digital transmitter 5 adopts a modified dipole antenna with a gain of 0dBi and a near-omnidirectional radiation direction. When the radiosonde 3 is used under extreme conditions such as passing over the top of the ground satellite navigation radiosonde receiver or flying too far away, this type of antenna design satisfies the following link budget formula with the sensitivity of the ground satellite navigation radiosonde receiver:

[0090] Pr = Pt + Gt + Gr - Lfs - Lother;

[0091] Where: Pr is the signal power received by the receiver, Pt is the transmit power of radiosonde 3, Gt and Gr are the transmit and receive antenna gains, Lfs is the free space path loss, Lfs=32.44+20lg(f)+20lg(d), where f is the frequency (MHz), d is the distance (km), 32.44 is the free space path loss constant, and Lother is other losses.

[0092] When the antenna passes overhead, the distance to the ground data receiver is 100km. Pt is taken as 25dBm, D as 100km, f as 403MHz, and Gt as the gain of the omnidirectional antenna passing overhead (4dBi). Lother considers the oscillation and polarization loss of radiosonde 3 as 6dBm and the axial antenna radiation gain of radiosonde 3 as -10dBm, resulting in a loss of 16dBm. The calculated Pr at overhead is -111.5dBm, which is less than the sensitivity of the ground satellite navigation radiosonde receiver (-117dBm), leaving a margin of 5.5dBm. When the descent slant distance of radiosonde 3 is 200km, D is taken as 200km, Gt as the gain of the omnidirectional antenna (5dBi), and Lother only considers the oscillation and polarization loss of radiosonde 3 as 6dBm. The calculated Pr at 200km is -106.5dBm, which is less than the sensitivity of the ground satellite navigation radiosonde receiver (-117dBm), leaving a margin of 10.5dBm, sufficient for use under extreme conditions.

[0093] During data transmission, a cyclic redundancy check (CRC) function was added, which can detect 100% of all odd-numbered random errors and burst errors of length ≤ k (where k is the order of the generator polynomial). To avoid data communication anomalies or interruptions caused by the radiosonde 3's swing or excessive descent speed, a data delay and repetitive transmission technique was adopted. Each transmission transmits not only the data at the current time T0, but also the detection data at T0-2 and T0-4 seconds. If the current signal quality is poor, resulting in missing data, it can be recovered after receiving subsequent transmissions, thereby solving the problem of unstable data reception and significantly improving the data acquisition rate. Due to the increase in sampling frequency, the amount of wireless data transmitted increases. To meet data transmission requirements and not affect receiver sensitivity, the data is compressed and packaged for transmission.

[0094] Wireless remote control module 11:

[0095] Composed of a wireless data transmission module, a self-contained power supply, a switch, diodes, and a controllable voltage regulator, it is installed in the lower part of the radiosonde 3. After receiving the operation commands and information from the ground wireless remote control equipment, the wireless remote control module 11 controls the power supply of the lithium battery 4 to cut off or turn on through the MCU. At the same time, it can also output to the digital transmitter 5 through the MCU of the wireless data transmission module to change the center carrier frequency.

[0096] Lithium battery 4:

[0097] The radiosonde 3 is powered by a low-temperature rechargeable lithium battery 4. The lithium battery 4 is connected to the mechanical switch 12 and the wireless remote control module 11 respectively. The working voltage is output through the voltage regulator module to power the digital transmitter 5, the data acquisition circuit 7, the high dynamic satellite navigation and positioning module 9 and the wireless remote control module 11.

[0098] Mechanical switch 12:

[0099] A mechanical DIP switch is provided on the outside of the housing 10 to facilitate power-off of the sounding instrument 3.

[0100] Casing 10:

[0101] The shell 10 is made of ABS material, which has high structural strength and good temperature resistance. The shell 10 is filled with thermal insulation foam material, which serves to insulate and absorb shock.

[0102] Currently, domestic radiosondes are generally carried by radiosonde balloons or parachutes. They detect atmospheric environmental parameters during the ascent or descent phase. As radiosonde balloons ascend, the ambient air pressure decreases significantly; after the balloon expands and bursts, the radiosonde falls to the ground. During parachute descent, the descent speed decreases as atmospheric density increases, occupying airspace and affecting flight safety. This invention adds a parachute line cutter to the radiosonde 3. Based on the radiosonde 3's position, air pressure, and other information, it determines whether the radiosonde 3 has fallen to a predetermined altitude or exceeded the landing area, automatically issuing a line-cutting command to sever the parachute lines. This allows the radiosonde to descend rapidly without the parachute's deceleration, and the parachute, without the radiosonde's gravitational pull, will also land quickly, achieving a rapid landing of the parachute-radiosonde target.

[0103] The specific implementation method of the rope cutter 8 is as follows:

[0104] The rope cutter 8 is fixed to the top of the radiosonde 3. The parachute rope 2 passes through the threading hole and is connected to the radiosonde 3. The cutter 17 is embedded in the groove of the housing 10 to ensure that it moves in the specified direction when under force, so that the rope cutter 8 can cut the parachute rope 2 after it works, so that the parachute 1 is separated from the radiosonde 3.

[0105] The ignition command for the rope cutter 8 is autonomously determined by the electrical signal input from the radiosonde 3. The radiosonde 3 has a built-in navigation and positioning module, which uses position information, speed information, and information collected by the air pressure sensor 6 to jointly determine whether the radiosonde 3 has fallen to the predetermined height or exceeded the landing area. When it falls to the predetermined height or exceeds the landing area, the radiosonde 3 issues a rope-cutting command.

[0106] The pyrotechnic gas generating device 16 is activated by the ignition current. After the radiosonde 3 provides the ignition current, the pyrotechnic gas generating device 16 works and generates a large amount of gas, which acts on the back of the cutter 17. As the thrust increases, when the thrust on the two shear pins 14 exceeds their own shear strength, the shear pins 14 break, and the cutter 17 moves forward under the thrust. The cutter 17 cuts the parachute rope 2 of the parachute 1.

[0107] like Figure 5 The following is the control procedure for cutting the rope on the radiosonde 3:

[0108] S1: Before using the radiosonde 3, set the minimum detection altitude H0=18000m, air pressure P0=75hPa, maximum landing area radius R0=200km, and the center position of the landing area (lat0, lon0) to the radiosonde 3.

[0109] S2: Before the meteorological rocket launch, the radiosonde 3 is turned on. The high-precision satellite navigation and positioning module, temperature sensor 13, air pressure sensor 6 and other components inside the radiosonde 3 begin to continuously detect data such as spatial position, speed, temperature, air pressure, wind speed and wind direction.

[0110] S3: The radiosonde 3 acquires data such as spatial position (latn, lonn, Hn), velocity (Vn), air pressure (Pn), temperature (Tn), and time (tn) from the detection data;

[0111] S4: Determine if the weather rocket has been launched: The sounding instrument 3, based on the change in velocity (Vn), if the acceleration (V... n -V n-1 ) / (t n -t n-1 ≥10g (g is the acceleration due to gravity, taken as 9.8m / s²) 2 If the duration is ≥3s, then the weather rocket has been launched;

[0112] S5: Determine if radiosonde 3 has exited the chamber: Based on the changes in the collected temperature data, if T... n -T n-1 ≥10℃, P n -P n-1 If the pressure is ≥10hPa, then the temperature and pressure data show a sudden change, indicating that the radiosonde 3 has been released from the meteorological rocket body to the outside of the rocket body;

[0113] S6: Determine if the descent has reached the predetermined altitude: After S4 and S5 are normal, the radiosonde 3 continuously judges the change in altitude (Hn) based on the spatial position information (latn, lonn, Hn). When Hn... n -H0≤0 and H n-1 When -H0≥0, the air pressure P nIf ≥P0, it is determined that the radiosonde 3 has fallen to the predetermined height;

[0114] S7: Determine if the impact area is outside the landing zone: After S4 and S5 are normal, the radiosonde 3 continuously determines the horizontal distance Rn between its horizontal position (latn, lonn) and the center of the landing zone (lat0, lon0) based on the spatial position information (latn, lonn, Hn). The calculation process for Rn is as follows:

[0115] R n =a×c;a=sin 2 [(lat n -lat0)×π / 180 / 2)]+cos(lat0×π / 180)×cos(lat n (×π / 180)×sin 2 [(lon n -lon0)×π / 180 / 2)]; c=2×atan2( , );

[0116] If R n -R0≥0 and R n-1 If -R0≤0, then radiosonde 3 is determined to be outside the impact zone.

[0117] S8: Issue a command to cut the sounding rope: When the sounding instrument 3 falls to the predetermined height or the position of the sounding instrument 3 exceeds the landing area, the sounding instrument 3 outputs a cut rope command to the rope cutter 8 to cut the sounding rope.

[0118] S9: Determine the landing location of radiosonde 3: Longitude of the location of radiosonde 3 (lat) n =lat n-1 ), latitude (lon) n =lon n-1 ), height (H) n =H n-1 If the sounding device 3 lands, then the sounding device 3 will land.

[0119] Currently, domestic sounding equipment is categorized by its detection altitude. For example, meteorological bureaus commonly use upper-air meteorological systems, whose detection altitude is significantly affected by balloon bursts, typically around 25km. Rocket-based sounding systems generally detect altitudes between 20 and 60km. Due to parachute descent speed limitations, operationally, sounding balloons carrying BeiDou radiosondes are often used to assist in measuring atmospheric parameters from the ground to an altitude of 20km. This results in discontinuities in the two sets of data measurements near 20km. Furthermore, the measured values ​​require correction due to the radiosonde's descent speed and various forms of thermal radiation. This invention proposes a data processing and stitching method. Based on corrected measurements, it weights and fuses data from the 18-20km altitude range to form ground-to-60km detection data, ensuring data accuracy, consistency, and completeness.

[0120] like Figure 6 As shown, the data processing and splicing method includes the following steps:

[0121] S1. Determine if radiosonde 3 has descended to an altitude of 18km. If H n If the distance is ≥18km, then continue the evaluation. If H n If the altitude is ≤18km, then extract the detection data at altitudes of 18 to 60km;

[0122] S2, Analysis includes temperature T n air pressure P n 3. Location data of the radiosonde. n lon n H n 3D velocity data from the radiosonde v x v y v z If the temperature sensor 13 data T n1 T n2 Both are normal. Take the average of the two values ​​as the actual measurement value. Otherwise, take the lower value measured by temperature sensor 13 as the actual measurement value, based on the axial velocity v of the radiosonde 3. z Data is used to determine whether radiosonde 3 landed normally. If the data is above 60km at various altitudes, v z If all exceed 200m / s, the detection is considered a failure and data processing is terminated.

[0123] S3. If step S2 is normal, then perform quality control on the altitude data from 18 to 60 km.

[0124] S4, The three-dimensional velocity data v from the radiosonde. x v y v z Spectral analysis was performed to determine the oscillation frequency range of radiosonde 3, and the three-dimensional velocity data v was analyzed. x v y v zPerform smoothing and filtering;

[0125] S5. Using polynomial fitting method based on three-dimensional velocity data v x v y v z Calculate three-dimensional acceleration data a x a y a z ;

[0126] S6. Using three-dimensional acceleration data a x a y a z Substituting the following wind field correction formula, for wind speed u s v s Make corrections:

[0127] (1);

[0128] (2);

[0129] S7. Based on the corrected speed information, substitute it into the wind speed and direction calculation formulas to synthesize the horizontal wind speed V and wind direction D:

[0130] (3);

[0131] (4);

[0132] S8. Based on the structural design of temperature sensor 13, solve the optimized temperature correction equation given by the World Meteorological Organization to obtain the actual atmospheric temperature detection value T. ∞ :

[0133] (5);

[0134] Among them, T f For measuring temperature values ​​using a thermistor, For pneumatic heating correction, r is the temperature recovery coefficient of the airflow over the thermistor surface, and v r C represents the relative velocity between the airflow and the thermistor. p The specific pressure heat capacity of air is taken as 1004 J / (kg·K). For the lag effect correction term, m T C is the heat capacity of the thermistor, A is the surface area of ​​the thermistor, and h is the surface area of ​​the thermistor. cs The coefficient of convective heat exchange between the thermistor surface and the air. The rate of temperature change of the thermistor over time is taken as 0.0028℃; For the correction term of solar radiation emitted from the ground and clouds, A mρ is the effective area of ​​the thermistor affected by solar radiation reflected from the ground and clouds. m α is the combined reflectance coefficient of the ground and clouds. s Let J be the absorptivity of the thermistor to solar radiation, and J be the solar constant, which is 1367 J / (s·m2). W is the correction term for the thermal loss of the measurement circuit. f To measure the heat generated by the Joule effect of electric current;

[0135] S9. Using the air pressure at an altitude of 20km as the initial value P0, based on the detection altitude H... n and the corrected temperature measurement value T ∞ Calculate the air pressure value P at each altitude using the static pressure formula:

[0136] (6);

[0137] Where H is the potential height at the desired altitude, H0 is the initial potential height (taken as 20000 m), and M is the average atmospheric molecular weight at altitude H (g). H Let H be the gravitational acceleration at height H, and R be the universal gas constant, taken as 8.314 J / (mol·K).

[0138] S10. Based on the air pressure value P and temperature detection value T at each altitude. ∞ Calculate the air density ρ at each altitude using the following formula:

[0139] (7);

[0140] S11. Iteratively calculate the temperature value, compare the temperature detection values ​​of two adjacent iterations, if the maximum difference is less than 0.01℃, stop the iteration, obtain the final temperature, air pressure, atmospheric density, and wind field measurement values ​​and proceed to step S12; otherwise, bring the temperature, air pressure, and density values ​​back into step S8 for iterative calculation.

[0141] S12. Synchronize temperature, air pressure, density, wind speed, and wind direction measurement data at the same time.

[0142] S13. Read data from the ground to a height of 20km using a sounding balloon;

[0143] S14. Compare the temperature difference between the weather balloon data and the near-space radiosonde 3 data in the overlapping altitude segment. Take the altitude with the smallest difference between 18km and 20km as the splicing altitude. Take the near-space radiosonde 3 data for 20 seconds above the splicing altitude and the weather balloon data for 20 seconds below the splicing altitude. Use polynomial fitting to smoothly connect the two data segments. Take the air pressure at the splicing point as P0 and recalculate the upward altitude to 60km according to the method in step S9. Calculate the atmospheric density according to the method in step S10.

[0144] S15. Store the data before and after processing into the database according to the prescribed format;

[0145] S16. Display the processed and spliced ​​data;

[0146] S17. Output data according to requirements.

[0147] During the descent phase, the radiosonde 3 is affected by complex environmental factors such as high descent velocity, thin air, and various types of thermal radiation. The temperature measurement values ​​and wind field calculation values ​​are not the true values ​​of the atmospheric environment and must be corrected. After the radiosonde 3 lands and completes its detection business, it begins to process the raw detection data and stitch it with the detection data from the ground to an altitude of 20km to form near-space environment detection data from the ground to an altitude of 60km.

[0148] The system integration and joint testing are detailed below:

[0149] The components are designed in a modular, universal, and standardized manner, employing standard components, general-purpose unit circuits, general-purpose electronic functional modules, general-purpose structural parts, and very large-scale integrated circuits to improve equipment integration and digitalization, and simplify circuit design. System integration testing includes hardware connection testing, performance testing, and environmental adaptability testing.

[0150] Hardware connection test: After powering on the radiosonde 3, the power was turned off and the frequency was changed via a ground-based wireless remote control device. After establishing a signal connection with the ground-based satellite navigation radiosonde receiver, satellite positioning data acquisition and data transmission were normal. Parameters such as temperature, air pressure, radiosonde 3 location information, and battery voltage were all obtained normally when viewed through the ground-based satellite navigation radiosonde receiver's display software.

[0151] Hardware performance testing: Based on the connection test, the real-time data received by the ground satellite navigation radiosonde receiver software was complete. Comparison of measured values ​​with data from the ground radiosonde base station and automatic weather station showed that the temperature sensor 13's measurement deviation was within 0.2℃, and the barometric pressure sensor 6's measurement deviation was within 1 hPa. Comparison with handheld BeiDou terminal positioning data showed that the latitude and longitude deviation was within 3m, and the altitude difference was within 7.5m, meeting the design specifications. At the mountaintop, with the lowest detection altitude (H0) and barometric pressure (P0) set at the same height as the ground, during the movement of the radiosonde 3 from the mountaintop to the ground, the radiosonde 3's measurement reached the standard for cutting the parachute rope 2, and the shearing pin 14 cut the parachute rope 2. The hardware functioned normally throughout the entire process.

[0152] Environmental adaptability testing: High and low temperature tests were conducted in an environment with temperatures ranging from -40℃ to +60℃; damp heat tests were conducted under conditions of humidity ≤98%RH (30±5℃); low-pressure tests were conducted under an environment with an atmospheric pressure of 1hPa; load tests were conducted under conditions of axial acceleration of +50g to -5g, lateral acceleration of ±5g (duration: 2 minutes), and maximum impact ≤100g (duration: 10 milliseconds). After all projects were completed, an inspection was conducted, and the radiosonde 3 was found to be functioning normally.

[0153] Reliability test: The radiosonde 3 was powered on and debugged to normal operation, and continued to run until the power was exhausted. During this period, the working status of the equipment was checked periodically. The radiosonde 3 transmitted data normally, and the data reporting rate exceeded 99.9%. After data processing, the data was compared with the data from surrounding automatic weather stations, and the data consistency was good.

[0154] In two flight tests in November 2023, the data acquisition rate exceeded 99.9%, the shears worked normally, and the data quality and accuracy were higher after processing and splicing and compared with standard atmospheric data, revealing more measurement details.

[0155] This invention has the function of in-situ measurement of air temperature, air pressure, and radiosonde 3 location information at altitudes below 60km from the ground to near space. The radiosonde 3 has high measurement accuracy, stable operation, and good environmental adaptability. It can significantly reduce problems such as long parachute-radiosonde loiter time, large landing area, and data packet loss during data transmission, ensuring data accuracy, consistency, and integrity, and achieving the goal of rapid landing of the radiosonde 3 and significantly improved data acquisition rate.

[0156] It should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention in any other way. Any modifications or equivalent changes made based on the technical essence of the present invention shall still fall within the scope of protection claimed by the present invention.

Claims

1. A near-space sounding instrument with a built-in rope cutter, characterized in that, It includes a parachute (1), parachute lines (2) and a radiosonde (3), wherein the parachute (1) is connected to the radiosonde (3) via the parachute lines (2); The radiosonde (3) includes a housing (10) and a lithium battery (4), a digital transmitter (5), a barometric pressure sensor (6), a data acquisition circuit (7), a high-dynamic satellite navigation and positioning module (9), a wireless remote control module (11), a mechanical switch (12), and a temperature sensor (13) installed in the housing (10). The lithium battery (4) powers the entire radiosonde (3). The high-dynamic satellite navigation and positioning module (9), the barometric pressure sensor (6), and the temperature sensor (13) are respectively connected to the data acquisition circuit (7). The data acquisition circuit (7) is connected to the digital transmitter (5). The digital transmitter (5) is connected to a ground satellite navigation radiosonde receiver through a ground antenna. The wireless remote control module (11) is connected to the ground wireless remote control equipment and the data acquisition circuit (7) respectively. It also includes a rope cutter (8). The housing (10) is provided with a threading hole. The paracord (2) passes through the threading hole and is connected to the sounding instrument (3). A cavity (15) communicating with the threading hole is provided on one side. The rope cutter (8) is installed in the cavity (15). The rope cutter (8) includes a shearing pin (14), a pyrotechnic gas generating device (16), and a cutter (17). The cutter (17) is fixed in the cavity (15) by the shearing pin (14). The pyrotechnic gas generating device (16) is fixed in the cavity (15). On the inner wall of the cavity (15) and between the back force-bearing surface of the cutter (17) and the bottom of the cavity (15), the pyrotechnic gas generating device (16) contains combustible gas and is connected to the data acquisition circuit (7). When the radiosonde (3) falls to a predetermined height or exceeds the fall area, the radiosonde (3) issues a rope-cutting command, the data acquisition circuit (7) outputs ignition current, and the pyrotechnic gas generating device (16) releases combustible gas, generating a driving force in the cavity (15) and acting on the back force-bearing surface of the cutter (17).

2. A near-space sounding instrument with a built-in rope cutter according to claim 1, characterized in that, The wireless remote control module (11) includes a wireless data transmission module and a controllable voltage regulator. The wireless data transmission module is connected to the wireless remote control device and the data acquisition circuit (7) respectively. The controllable voltage regulator is connected to the lithium battery (4). The wireless data transmission module receives the ground equipment remote control command issued by the wireless remote control device, controls the voltage regulator to start and stop, and realizes the control of the lithium battery (4) switch. At the same time, it receives the command from the data acquisition circuit (7) to modify the frequency of the radiosonde (3).

3. A near-space sounding instrument with a built-in rope cutter according to claim 1, characterized in that, The pressure sensor (6) is a silicon piezoresistive pressure sensor that transmits the collected pressure signal to the data acquisition circuit (7).

4. A near-space sounding instrument with a built-in rope cutter according to claim 1, characterized in that, The temperature sensor (13) consists of two beaded thermistors, which transmit the collected ambient temperature signal to the data acquisition circuit (7) through a conversion circuit.

5. A near-space sounding instrument with a built-in rope cutter according to claim 1, characterized in that, The high dynamic satellite navigation and positioning module (9) includes a satellite receiving antenna and a dual-system satellite positioning receiver. The satellite receiving antenna is signal-connected to the dual-system satellite positioning receiver. The satellite receiving antenna transmits the received Beidou satellite radio frequency signals to the dual-system satellite positioning receiver. The dual-system satellite positioning receiver is connected to the data acquisition circuit (7).

6. A near-space sounding instrument with a built-in rope cutter according to claim 1, characterized in that, The data acquisition circuit (7) uses 5Hz high-frequency sampling to collect and compress the information from the barometer (6), temperature sensor (13), lithium battery (4), and radiosonde (3) and transmit it to the digital transmitter (5).

7. A near-space sounding instrument with a built-in rope cutter according to claim 1, characterized in that, The digital transmitter (5) includes a wireless transmitter chip and a linear power amplifier. The wireless transmitter chip is connected to the data acquisition circuit (7), modulates and outputs the detection data of the radiosonde (3), amplifies it after being amplified by the linear power amplifier, and transmits it to the ground satellite navigation radiosonde receiver through the ground antenna using a data combination delay repetition transmission mechanism.

8. A near-space sounding instrument with a built-in rope cutter according to claim 1, characterized in that, The shell (10) is filled with thermal insulation material.

9. The data processing and splicing method according to any one of claims 1-8, characterized in that, Includes the following steps: S1. Determine whether the radiosonde (3) has descended to an altitude of 18km. If H n If the distance is ≥18km, then continue the evaluation. If H n If the altitude is ≤18km, then extract the detection data at altitudes of 18 to 60km; S2, Analysis includes temperature T n air pressure P n 1. Radiosonde (3) Position data lat n lon n H n , radiosonde (3) three-dimensional velocity data v x v y v z If the temperature sensor (13) data T n1 T n2 Both are normal. Take the average of the two as the actual measured value. Otherwise, take the measured value of the temperature sensor (13) with the lower data as the actual measured value. According to the celestial velocity v of the radiosonde (3) z Data is used to determine whether the radiosonde (3) landed normally. If the v value is below 60km at various altitudes... z If all exceed 200m / s, the detection is considered a failure and data processing is terminated. S3. If step S2 is normal, then perform quality control on the altitude data from 18 to 60 km. S4. Three-dimensional velocity data v of the radiosonde (3) x v y v z Spectral analysis was performed to determine the oscillation frequency range of the radiosonde (3), and the three-dimensional velocity data v was analyzed. x v y v z Perform smoothing and filtering; S5. Using polynomial fitting method based on three-dimensional velocity data v x v y v z Calculate three-dimensional acceleration data a x a y a z ; S6. Using three-dimensional acceleration data a x a y a z Substituting the following wind field correction formula, for wind speed u s v s Make corrections: （1）； （2）； S7. Based on the corrected speed information, substitute it into the wind speed and wind direction calculation formulas to synthesize the horizontal wind speed V and wind direction D: （3）； （4）； S8. Based on the structural design of the temperature sensor (13), solve the optimized temperature correction equation given by the World Meteorological Organization to obtain the actual atmospheric temperature detection value T. ∞ : （5）； Among them, T f For measuring temperature values ​​using a thermistor, For pneumatic heating correction, r is the temperature recovery coefficient of the airflow over the thermistor surface, and v r C represents the relative velocity between the airflow and the thermistor. p The specific pressure heat capacity of air is taken as 1004 J / (kg·K). For the lag effect correction term, m T C is the heat capacity of the thermistor, A is the surface area of ​​the thermistor, and h is the surface area of ​​the thermistor. cs The coefficient of convective heat exchange between the thermistor surface and the air. The rate of temperature change of the thermistor over time is taken as 0.0028℃; For the correction term of solar radiation emitted from the ground and clouds, A m ρ is the effective area of ​​the thermistor affected by solar radiation reflected from the ground and clouds. m α is the combined reflectance coefficient of the ground and clouds. s Let J be the absorptivity of the thermistor to solar radiation, and J be the solar constant, which is 1367 J / (s·m2). W is the correction term for the thermal loss of the measurement circuit. f To measure the heat generated by the Joule effect of electric current; S9. Using the air pressure at an altitude of 20km as the initial value P0, based on the detection altitude H... n and the corrected temperature measurement value T ∞ Calculate the air pressure value P at each altitude using the static pressure formula: （6）； Where H is the potential height at the desired altitude, H0 is the initial potential height (taken as 20000 m), and M is the average atmospheric molecular weight at altitude H (g). H Let H be the gravitational acceleration at height H, and R be the universal gas constant, taken as 8.314 J / (mol·K). S10. Based on the air pressure value P and temperature detection value T at each altitude. ∞ Calculate the air density ρ at each altitude using the following formula: （7）； S11. Iteratively calculate the temperature value, compare the temperature detection values ​​of two adjacent iterations, if the maximum difference is less than 0.01℃, stop the iteration, obtain the final temperature, air pressure, atmospheric density, and wind field measurement values ​​and proceed to step S12; otherwise, bring the temperature, air pressure, and density values ​​back into step S8 for iterative calculation. S12. Synchronize temperature, air pressure, density, wind speed, and wind direction measurement data at the same time. S13. Read data from the ground to a height of 20km using a sounding balloon; S14. Compare the temperature difference between the weather balloon detection data and the near-space radiosonde (3) data in the overlapping altitude segment. Take the altitude with the smallest difference between 18km and 20km as the splicing altitude. Take the near-space radiosonde (3) data for 20 seconds above the splicing altitude and the weather balloon detection data for 20 seconds below the splicing altitude. Use polynomial fitting to smoothly connect the two data segments. Take the air pressure at the splicing point as P0. Recalculate the upward altitude to 60km according to the method in step S9. Calculate the atmospheric density according to the method in step S10. S15. Store the data before and after processing into the database according to the prescribed format; S16. Display the processed and spliced ​​data; S17. Output data according to requirements.

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