Multi-frequency-point carrier phase smooth surveying and mapping measurement centimeter-level positioning device

Abstract

The invention discloses a multi-frequency-point carrier phase smooth surveying and mapping measurement centimeter-level positioning device, and belongs to the technical field of unmanned aerial vehicle surveying and mapping positioning, the device comprises a fuselage and a main control module, the peripheral side of the fuselage is uniformly provided with a plurality of fan connecting rods, and one end, far away from the fuselage, of each fan connecting rod is fixedly connected with a driving fan; bottom supporting legs are symmetrically arranged at the bottom of the machine body and extend in the direction away from the machine body to support the machine body, a rotating base is fixedly arranged at the bottom of the machine body, a surveying and mapping base is rotatably arranged at the bottom of the rotating base, and four surveying and mapping connecting rods are evenly arranged on the outer side of the surveying and mapping base. According to the surveying and mapping measurement centimeter-level positioning device with the smooth multi-frequency-point carrier phase, the positioning performance in a complex environment is remarkably improved, and higher precision, higher response speed and higher environmental adaptability are brought to surveying and mapping measurement work.

Description

Technical Field

[0001] This invention relates to the field of UAV mapping and positioning technology, and more specifically, to a multi-frequency carrier phase smoothing mapping and measurement centimeter-level positioning device. Background Technology

[0002] In the traditional field of surveying and mapping, achieving centimeter-level positioning faces numerous challenges. On the one hand, in complex terrain environments, satellite signals are easily affected by obstruction and reflection, leading to unstable signal strength and significant phase deviations, making it difficult to guarantee positioning accuracy. For example, in mountainous areas and densely populated urban areas, satellite signals may be reflected multiple times, generating multipath effects and interfering with positioning accuracy. On the other hand, when satellite signals experience sudden changes, traditional positioning devices have slow response times and cannot adjust their positioning strategies in a timely manner, resulting in significant positioning delays and impacting the real-time performance and efficiency of surveying work.

[0003] Furthermore, traditional positioning devices often lack a collaborative mechanism between multiple modules. Individual functional modules, such as signal acquisition, calibration, and inertial assistance, typically operate independently, failing to provide a rapid overall response based on actual conditions. For example, when the signal acquisition module detects an anomaly, it cannot quickly trigger the calibration and inertial assistance modules to work collaboratively, resulting in a significant decrease in positioning accuracy and stability under poor signal conditions. Simultaneously, traditional devices lack effective countermeasures for the impact of external factors such as vibration, temperature, and lighting on positioning, making it difficult to maintain high-precision positioning in complex and changing environments. Summary of the Invention

[0004] The purpose of this invention is to provide a centimeter-level positioning device for mapping and measurement with multi-frequency carrier phase smoothing, so as to solve the problems mentioned in the background art.

[0005] A multi-frequency carrier phase smoothing surveying and measurement centimeter-level positioning device includes a body and a main control module. Multiple fan connecting rods are evenly arranged around the periphery of the body, with a drive fan fixedly connected to the end of each fan connecting rod furthest from the body. Symmetrical bottom support legs are arranged at the bottom of the body, extending away from the body to support it. A rotating base is fixedly mounted at the bottom of the body, and a surveying base is rotatably mounted on the bottom of the rotating base. Four surveying connecting rods are evenly arranged on the outer side of the surveying base, with a direction adjustment base fixedly mounted at one end of each of the four surveying connecting rods. A surveying electrical box is rotatably mounted on the bottom of each of the four direction adjustment bases. Each end of the mapping box is fixedly equipped with a mapping lens. The body is equipped with a multi-frequency carrier phase synchronization acquisition module based on satellite radio beacon positioning technology, an adaptive frequency phase deviation calibration module, and an IMU inertial auxiliary fusion unit. The main control module is integrated inside the body and is electrically connected to the above three modules. It also constructs a dynamic collaborative triggering logic: when the multi-frequency acquisition module detects that the signal-to-noise ratio of any frequency point is lower than the threshold, it immediately sends a "high-priority calibration command" to the calibration module and simultaneously activates the "high-frequency sampling mode" of the IMU, increasing the sampling frequency from 100Hz to 500Hz, realizing a cross-module linkage response of "signal anomaly - calibration acceleration - inertial assistance".

[0006] Preferably, the multi-frequency acquisition module is installed on the top of the fuselage, the adaptive calibration module and the main control module are integrated in the center of the fuselage, and the IMU unit is installed close to the multi-frequency acquisition module. Through the above-mentioned collaborative mechanism, centimeter-level positioning in complex terrain is achieved using satellite radio beacon signal transmission, and the positioning response delay during signal abrupt changes is ≤50ms. The multi-frequency carrier phase synchronization acquisition module includes a multi-frequency receiving antenna, a high-speed analog-to-digital converter, and an attitude adaptive tuning submodule. The multi-frequency receiving antenna is fixed to the outside of the fuselage by a shock-absorbing bracket. The attitude adaptive tuning submodule is connected to the tilt sensor of the UAV flight control system to obtain the fuselage pitch / roll angle in real time, with a range of ±15°. When the fuselage tilt angle is >5°, the submodule finely adjusts the angle of the receiving surface of the multi-frequency receiving antenna through a piezoelectric drive mechanism so that the multi-frequency receiving antenna always maintains the optimal angle with the direction of satellite signal propagation. The high-speed analog-to-digital converter is equipped with a coaxial cable and is connected to the multi-frequency receiving antenna through the coaxial cable to synchronously sample the L1, L2, and L5 frequency points. The integrity of the signal sampling after tuning is improved by ≥30%.

[0007] Preferably, in the dynamic deviation model of the adaptive frequency point phase deviation calibration module, in addition to Kalman filtering, a satellite signal spatiotemporal correlation factor is also introduced: the real-time position of the UAV and the pre-installed satellite ephemeris data are obtained through the main control module, the relative motion trajectory of the satellite and the UAV corresponding to each frequency point is calculated, and the trajectory overlap is used as the weight coefficient for phase deviation correction. For frequency points with strong trajectory correlation, a weighted fusion of "current phase + average phase of the previous 3 cycles" is adopted with a weight of 7:3. For frequency points with weak correlation, only the current phase data is retained.

[0008] Preferably, when the satellite signal is normal, the IMU data weight is dynamically adjusted according to the stability of the multi-frequency fusion phase; when the satellite signal is interrupted, the IMU drift correction coefficient is dynamically switched according to the satellite positioning accuracy in the last 3 seconds before the interruption to avoid high-error satellite data from contaminating the IMU calibration.

[0009] Preferably, the attitude adaptive tuning submodule also integrates a fan speed-vibration characteristic correlation unit: the real-time speed of the driving fan is obtained through the speed sensor built into the fan connecting rod, and a mapping database of speed-vibration frequency / amplitude is established; when the speed change rate is >500rpm / s, the unit calls the matching vibration parameters in the database to perform "speed prediction compensation" on the phase data output by the high-speed analog-to-digital converter, rather than passively responding to vibration.

[0010] Preferably, the frequency point dynamic switching unit of the multi-frequency receiving antenna is equipped with a polarization characteristic matching submodule. The polarization characteristic matching submodule pre-stores polarization characteristic parameters L1 (right-hand circular polarization), L2 (right-hand circular polarization), and L5 (left-hand circular polarization). Combined with the UAV's GPS position and a three-dimensional terrain database, it identifies the material of the obstruction. Based on the reflection polarization attenuation law of different materials, it dynamically adjusts the frequency point switching threshold.

[0011] Preferably, the adaptive frequency point phase deviation calibration module also associates the slope factor of the survey area: extracts the terrain slope of the current position of the UAV from the pre-installed three-dimensional terrain library, and when the slope is >30°, automatically extends the historical data backtracking length of the high signal-to-noise ratio frequency point from 10 cycles to 20 cycles, and introduces the "slope-phase deviation amplification coefficient".

[0012] Preferably, the IMU inertial-assisted fusion unit is equipped with a temperature adaptive drift calibration submodule. The temperature adaptive drift calibration submodule introduces multi-frequency phase noise cross-validation: when the satellite signal is normal, the phase noise standard deviation of L1, L2, and L5 frequencies is calculated in real time. When the mean of the three is <0.05 weeks, the satellite positioning data of that period is used to perform "high-precision calibration" on the IMU temperature drift model; when the mean is >0.2 weeks, the calibration is paused and the most recent high-precision calibration result is used.

[0013] Preferably, a multi-path reflection signal recognition unit is provided in the vibration adaptive phase compensation sub-module. The multi-path reflection signal recognition unit has the ability to classify reflection source types: by analyzing the spectral characteristics of the reflection signal, the reflection sources are divided into three categories: ground, building, and water surface; for different types of reflections, the sliding window filtering parameters are dynamically adjusted, and the upper limit of the fusion weight is set correspondingly.

[0014] Preferably, a satellite signal occlusion prediction model is provided in the frequency point dynamic switching unit. The satellite signal occlusion prediction model introduces real-time ambient light intensity parameters: a light intensity sensor is installed on the top of the fuselage. When the light intensity > 50000 lux, the satellite signal reception sensitivity will decrease by 15% - 20%, and the model incorporates this attenuation coefficient into the occlusion probability calculation; when the light intensity < 5000 lux, the sensitivity increases, and the occlusion probability is corrected by multiplying the original calculated value by 0.8.

[0015] Compared with the prior art, the advantages of the present invention are as follows: This multi-frequency carrier phase smoothed surveying and mapping metering centimeter-level positioning device has a series of excellent beneficial effects, significantly improving the positioning performance in complex environments, bringing higher accuracy, faster response speed, and stronger environmental adaptability to the surveying and mapping metering work.

[0016] Generally speaking, through the innovative design and collaborative work of multiple modules, the device effectively overcomes the deficiencies of traditional positioning devices. The multi-frequency carrier phase synchronous acquisition module, adaptive frequency point phase deviation calibration module, and IMU inertial assistance fusion unit based on satellite radio beacon positioning technology achieve an efficient cross-module linkage response of "signal anomaly - calibration acceleration - inertial assistance" under the dynamic collaborative trigger logic constructed by the main control module, ensuring fast and accurate centimeter-level positioning in various complex situations.

[0017] Specifically, the attitude adaptive tuning sub-module in the multi-frequency carrier phase synchronous acquisition module obtains the fuselage inclination angle in real time by connecting with the inclination sensor of the UAV flight control system. When the inclination angle is greater than 5°, it can automatically fine-tune the receiving surface angle of the multi-frequency receiving antenna to keep the optimal angle with the satellite signal propagation direction. This design greatly improves the signal reception quality. The signal sampling integrity after tuning is increased by ≥ 30%, providing a reliable data basis for subsequent high-precision positioning. At the same time, the high-speed analog-to-digital converter synchronously samples the L1, L2, and L5 frequency points, ensuring the comprehensiveness and timeliness of data acquisition.

[0018] The adaptive frequency-point phase deviation calibration module introduces a satellite signal spatiotemporal correlation factor based on traditional Kalman filtering. By calculating the relative motion trajectories of the satellite and the UAV at each frequency point, the trajectory overlap is used as a weighting coefficient for phase deviation correction. Different data fusion methods are employed for frequencies with different correlations, effectively improving the accuracy of phase deviation calibration and further enhancing positioning precision. Furthermore, by associating the mapping area with the slope factor, the module automatically adjusts the historical data backtracking length for high signal-to-noise ratio frequencies based on the terrain slope and introduces a "slope-phase deviation amplification coefficient," enabling the calibration module to better adapt to signal variations under different terrain conditions.

[0019] The IMU (Inertial Aided Fusion Unit) employs a nonlinear dynamic weight fusion strategy. When satellite signals are normal, it dynamically adjusts the IMU data weights based on the stability of the multi-frequency fused phase. When satellite signals are interrupted, it dynamically switches the IMU drift correction coefficient based on the satellite positioning accuracy of the last 3 seconds before the interruption, avoiding contamination of IMU calibration by high-error satellite data. Its internal temperature adaptive drift calibration submodule utilizes multi-frequency phase noise cross-validation. When satellite signals are normal and the phase noise standard deviation meets certain conditions, it performs "high-precision calibration" of the IMU temperature drift model, ensuring the accuracy of IMU data under different temperature environments, thereby improving the stability and reliability of the entire positioning device in complex environments.

[0020] Furthermore, the fan speed-vibration characteristic correlation unit integrated in the attitude adaptive tuning submodule establishes a mapping database of speed-vibration frequency / amplitude. When the fan speed change rate is >500 rpm / s, it performs "speed prediction compensation" on the phase data output by the high-speed analog-to-digital converter, rather than passively responding to vibration, effectively reducing vibration interference on positioning data. The polarization characteristic matching submodule within the frequency dynamic switching unit of the multi-frequency receiving antenna, combined with the UAV's GPS location and a 3D terrain database, identifies the material of obstructions and dynamically adjusts the frequency switching threshold based on the reflection polarization attenuation law of different materials, further optimizing signal reception. The multipath reflection signal identification unit within the vibration adaptive phase compensation submodule classifies reflection sources by analyzing the spectral characteristics of reflected signals and dynamically adjusts the sliding window filtering parameters and fusion weight upper limit to reduce the impact of multipath effects. The satellite signal obstruction prediction model within the frequency dynamic switching unit incorporates real-time ambient light intensity parameters and adjusts the satellite signal reception sensitivity and obstruction probability calculation based on light intensity changes, enabling the positioning device to better adapt to signal changes under different lighting conditions. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a schematic diagram of the module structure of the present invention; Figure 3 This is a schematic diagram of the bottom structure of the fuselage of the present invention; Figure 4 This is a schematic diagram of the surveying base structure of the present invention; Figure 5 This is a side view of the present invention; Figure 6 This is a schematic diagram of the bottom structure of the present invention.

[0022] The following are the labels in the diagram: 1. Body; 10. Fan connecting rod; 11. Drive fan; 12. Bottom support leg; 13. Multi-frequency receiving antenna; 2. Rotating base; 20. Surveying base; 21. Surveying connecting rod; 22. Direction adjustment base; 23. Surveying electrical box; 24. Surveying lens. Detailed Implementation

[0023] Example: Please refer to Figures 1-6 A centimeter-level positioning device for multi-frequency carrier phase smoothing mapping and measurement includes a fuselage 1 and a main control module. Multiple fan connecting rods 10 are evenly arranged around the fuselage 1, with one end of each fan connecting rod 10 connected to a drive fan 11. Symmetrical bottom support legs 12 support the fuselage 1 at its bottom, and a rotating base 2 is fixed to the bottom. A mapping base 20 is rotatably connected to the bottom of the rotating base 2. Four mapping connecting rods 21 are evenly arranged on the outer side of the mapping base 20. A direction adjustment base 23 is fixedly installed at one end of each of the four mapping connecting rods 21. A mapping electrical box 22 is rotatably installed at the bottom of each of the four direction adjustment bases 23, and a mapping lens (24) is fixedly installed at one end of each of the four mapping electrical boxes 22. The fuselage 1 is equipped with a multi-frequency carrier phase synchronization acquisition module based on satellite radio beacon positioning technology, an adaptive frequency phase deviation calibration module, and an IMU inertial-assisted fusion unit. The main control module is integrated inside the housing 1 and is electrically connected to the three modules mentioned above. It also constructs a dynamic collaborative triggering logic: when the multi-frequency acquisition module detects that the signal-to-noise ratio of any frequency point is lower than the threshold, it sends a "high-priority calibration command" to the calibration module and activates the "high-frequency sampling mode" of the IMU, increasing the sampling frequency from 100Hz to 500Hz.

[0024] Supported and connected by various components, and utilizing the collaborative work of multiple modules, the main control module triggers cross-module linkage based on signal conditions. When a signal is abnormal, the main control module instructs the calibration module to accelerate calibration, while simultaneously increasing the sampling frequency of the IMU to assist in positioning. This achieves centimeter-level positioning in complex terrain. Through rapid inter-module linkage, it can respond promptly to sudden signal changes, effectively improving the accuracy and timeliness of positioning. The positioning response delay during signal changes is ≤50ms, meeting the high precision and real-time requirements of surveying and metrology.

[0025] Specifically, the multi-frequency acquisition module is installed on the top of fuselage 1, the adaptive calibration module and the main control module are integrated in the center inside fuselage 1, and the IMU unit is installed close to the multi-frequency acquisition module. The multi-frequency carrier phase synchronization acquisition module includes a multi-frequency receiving antenna 13, a high-speed analog-to-digital converter, and an attitude adaptive tuning submodule. The multi-frequency receiving antenna 13 is fixed to the outside of fuselage 1 by a shock-absorbing bracket. The attitude adaptive tuning submodule is connected to the tilt sensor of the UAV flight control system to acquire the pitch / roll angle of fuselage 1 in real time (range ±15°). When the tilt angle of fuselage 1 is >5°, the submodule finely adjusts the angle of the receiving surface of the multi-frequency receiving antenna 13 through a piezoelectric drive mechanism. A coaxial cable is installed inside the high-speed analog-to-digital converter and connected to the multi-frequency receiving antenna 13 to synchronously sample frequencies L1, L2, and L5.

[0026] Each module is installed in a specific location. The multi-frequency receiving antenna receives signals, and the attitude adaptive tuning submodule adjusts the antenna angle according to the fuselage tilt angle. The high-speed analog-to-digital converter synchronously samples the frequency signals. Optimized module layout improves signal reception quality. The attitude adaptive tuning submodule ensures that the multi-frequency receiving antenna always maintains the optimal angle with the satellite signal propagation direction. The integrity of the signal sampling after tuning is improved by ≥30%, providing a good data foundation for high-precision positioning.

[0027] Specifically, in the dynamic deviation model of the adaptive frequency point phase deviation calibration module, in addition to Kalman filtering, a satellite signal spatiotemporal correlation factor is introduced. The main control module acquires the real-time position of the UAV and pre-installed satellite ephemeris data, calculates the relative motion trajectory between the satellite and the UAV for each frequency point, and uses the trajectory overlap as a weighting coefficient for phase deviation correction. For frequencies with strong trajectory correlation, a weighted fusion of "current phase + average phase of the previous 3 cycles" is used with a weight ratio of 7:3. For weakly correlated frequencies, only the current phase data is retained.

[0028] The relative motion trajectories of the satellite and the UAV are calculated using data acquired by the main control module, and the phase deviation is corrected based on the trajectory overlap. To improve the accuracy of phase deviation calibration, the spatiotemporal correlation of satellite signals is considered, and different fusion methods are used for different correlation frequencies, making the calibration more consistent with actual signal conditions and further improving positioning accuracy.

[0029] Specifically, the IMU inertial assisted fusion unit adopts a nonlinear dynamic weight fusion strategy: when the satellite signal is normal, the IMU data weight is dynamically adjusted according to the stability of the multi-frequency fusion phase; when the satellite signal is interrupted, the IMU drift correction coefficient is dynamically switched according to the satellite positioning accuracy in the last 3 seconds before the interruption.

[0030] Based on satellite signal conditions, the IMU data weights and drift correction coefficients are dynamically adjusted. Under varying satellite signal conditions, IMU data is utilized appropriately to assist positioning. When satellite signals are normal, weights are optimized to improve positioning stability; when signals are interrupted, high-error satellite data is prevented from affecting IMU calibration, thus improving the overall reliability of the positioning device in complex environments.

[0031] Specifically, the attitude adaptive tuning submodule also integrates a fan speed-vibration characteristic correlation unit: it obtains the real-time speed of the driving fan 11 through the speed sensor built into the fan connecting rod 10, and establishes a mapping database of speed-vibration frequency / amplitude. When the speed change rate is >500 rpm / s, the unit calls the matching vibration parameters in the database to perform "speed prediction compensation" on the phase data output by the high-speed analog-to-digital converter.

[0032] The fan speed is obtained using a speed sensor, and the phase data is pre-compensated based on a mapping database. This effectively reduces the interference of fan vibration on positioning data. By predicting and compensating for vibration effects in advance, rather than passively responding, the accuracy and stability of positioning data are improved.

[0033] Specifically, the frequency point dynamic switching unit of the multi-frequency receiving antenna 13 is equipped with a polarization characteristic matching submodule. The polarization characteristic matching submodule pre-stores polarization characteristic parameters of L1 (right-hand circular polarization), L2 (right-hand circular polarization), and L5 (left-hand circular polarization). Combined with the UAV's GPS position and three-dimensional terrain database, it identifies the material of the obstruction and dynamically adjusts the frequency point switching threshold according to the reflection polarization attenuation law of different materials.

[0034] The polarization characteristic matching submodule combines multiple pieces of information to identify the material of obstructions and adjusts the frequency switching threshold based on the material characteristics. This optimizes signal reception by dynamically adjusting the frequency switching strategy according to the impact of different obstruction materials on the signal, improving signal reception performance and ensuring optimal frequency selection for positioning even in complex environments.

[0035] Specifically, the adaptive frequency point phase deviation calibration module also associates the slope factor of the survey area: it extracts the terrain slope of the current position of the UAV from the pre-installed 3D terrain library. When the slope is greater than 30°, it automatically extends the historical data backtracking length of high signal-to-noise ratio frequency points from 10 cycles to 20 cycles and introduces the "slope-phase deviation amplification coefficient".

[0036] The calibration module adjusts the historical data backtracking length and correlation coefficients for high signal-to-noise ratio frequencies based on terrain slope. This allows the calibration module to better adapt to signal variations under different terrain conditions. In complex terrain with steep slopes, extending the data backtracking length and introducing correlation coefficients improves the accuracy of phase deviation calibration, thereby enhancing positioning accuracy.

[0037] Specifically, the IMU inertial-assisted fusion unit has a temperature adaptive drift calibration submodule. The temperature adaptive drift calibration submodule introduces multi-frequency phase noise cross-validation: when the satellite signal is normal, the phase noise standard deviation of L1, L2 and L5 frequencies is calculated in real time. When the mean of the three is <0.05 weeks, the satellite positioning data of that period is used to perform "high-precision calibration" on the IMU temperature drift model; when the mean is >0.2 weeks, the calibration is paused and the most recent high-precision calibration result is used.

[0038] By calculating the standard deviation of phase noise at multiple frequency points, the mean value is used to determine whether to perform high-precision calibration of the IMU temperature drift model. This ensures the accuracy of IMU data under different temperature environments. Cross-validation using multi-frequency phase noise is employed to reasonably calibrate the temperature drift model, thereby improving the stability and reliability of the positioning device under various temperature conditions.

[0039] Specifically, the vibration adaptive phase compensation submodule includes a multipath reflection signal identification unit, which has the ability to classify reflection source types: by analyzing the spectral characteristics of the reflected signals, the reflection sources are divided into three categories: ground, buildings, and water surfaces. For different types of reflections, the sliding window filtering parameters are dynamically adjusted, and the upper limit of the fusion weight is set accordingly. The identification unit analyzes the spectral characteristics of reflected signals to classify reflection sources, and adjusts filtering parameters and fusion weight upper limits for different types. This reduces the impact of multipath effects by employing different processing methods for different reflection sources, optimizing signal processing, improving positioning accuracy, and minimizing interference from multipath reflected signals.

[0040] Specifically, a satellite signal obstruction prediction model is set up in the frequency dynamic switching unit. The satellite signal obstruction prediction model incorporates real-time ambient light intensity parameters: a light intensity sensor is installed on the top of fuselage 1. When the light intensity is >50000 lux, the satellite signal receiving sensitivity decreases by 15%-20%, and the model incorporates this attenuation coefficient into the obstruction probability calculation; when the light intensity is <5000 lux, the sensitivity increases, and the obstruction probability is corrected by multiplying the original calculated value by 0.8.

[0041] By utilizing a light intensity sensor to acquire light intensity, a satellite signal obstruction prediction model adjusts the satellite signal receiving sensitivity and obstruction probability calculations based on the light intensity. This enables the positioning device to better adapt to signal variations under different lighting conditions. By considering the impact of light intensity on signal reception, the dynamic frequency switching strategy is optimized, improving the accuracy and stability of positioning.

[0042] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely preferred examples and are not intended to limit the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A multi-frequency carrier phase smoothing mapping and measurement centimeter-level positioning device, comprising a fuselage (1) and a main control module, characterized in that: Multiple fan connecting rods (10) are evenly arranged around the body (1), and a drive fan (11) is fixedly connected to one end of each fan connecting rod (10) away from the body (1); bottom support legs (12) are symmetrically arranged at the bottom of the body (1), and the bottom support legs (12) extend away from the body (1) to support the body (1); a rotating base (2) is fixedly arranged at the bottom of the body (1), and a surveying base (20) is rotatably arranged at the bottom of the rotating base (2); four surveying connecting rods (21) are evenly arranged on the outer side of the surveying base (20), and a direction adjustment base (23) is fixedly arranged at one end of each of the four surveying connecting rods (21); a surveying base (23) is rotatably arranged at the bottom of each of the four direction adjustment bases (23). The four surveying electrical boxes (22) are each fixedly equipped with a surveying lens (24) at one end. The fuselage (1) is equipped with a multi-frequency carrier phase synchronization acquisition module, an adaptive frequency phase deviation calibration module and an IMU inertial auxiliary fusion unit based on satellite radio beacon positioning technology. The main control module is integrated inside the fuselage (1) and is electrically connected to the above three modules respectively. It also constructs a dynamic collaborative triggering logic: when the multi-frequency acquisition module detects that the signal-to-noise ratio of any frequency point is lower than the threshold, it immediately sends a "high-priority calibration command" to the calibration module and simultaneously activates the "high-frequency sampling mode" of the IMU. The sampling frequency is increased from 100Hz to 500Hz, realizing the cross-module linkage response of "signal abnormality - calibration acceleration - inertial assistance".

2. The centimeter-level positioning device for mapping and measurement with multi-frequency carrier phase smoothing according to claim 1 is characterized in that: The multi-frequency acquisition module is installed on the top of the fuselage (1), the adaptive calibration module and the main control module are integrated in the center of the fuselage (1), and the IMU unit is installed close to the multi-frequency acquisition module; through the above-mentioned collaborative mechanism, centimeter-level positioning under complex terrain is achieved by using satellite radio beacon signal transmission, and the positioning response delay during signal change is ≤50ms. The multi-frequency carrier phase synchronization acquisition module includes a multi-frequency receiving antenna (13), a high-speed analog-to-digital converter and an attitude adaptive tuning submodule; the multi-frequency receiving antenna (13) is fixed to the outside of the fuselage (1) by a shock-absorbing bracket, and the attitude The adaptive tuning submodule is connected to the tilt sensor of the UAV flight control system to obtain the pitch / roll angle of the fuselage (1) in real time, with a range of ±15°. When the tilt angle of the fuselage (1) is greater than 5°, the submodule finely adjusts the angle of the receiving surface of the multi-frequency receiving antenna (13) through the piezoelectric drive mechanism so that the multi-frequency receiving antenna (13) always maintains the optimal angle with the direction of satellite signal propagation. The high-speed analog-to-digital converter is equipped with a coaxial line and is connected to the multi-frequency receiving antenna (13) through the coaxial line to synchronously sample the L1, L2, and L5 frequency points. The integrity of the signal sampling after tuning is improved by ≥30%.

3. The centimeter-level positioning device for mapping and measurement with multi-frequency carrier phase smoothing according to claim 2 is characterized in that: In the dynamic deviation model of the adaptive frequency point phase deviation calibration module, in addition to Kalman filtering, a satellite signal spatiotemporal correlation factor is also introduced: the real-time position of the UAV and the pre-installed satellite ephemeris data are obtained through the main control module, the relative motion trajectory of the satellite and the UAV corresponding to each frequency point is calculated, and the trajectory overlap is used as the weight coefficient for phase deviation correction. For frequency points with strong trajectory correlation, a weighted fusion of "current phase + average phase of the previous 3 cycles" is adopted with a weight of 7:

3. For frequency points with weak correlation, only the current phase data is retained.

4. The centimeter-level positioning device for mapping and measurement with multi-frequency carrier phase smoothing according to claim 3 is characterized in that: The IMU inertial-assisted fusion unit adopts a nonlinear dynamic weight fusion strategy: when the satellite signal is normal, the IMU data weight is dynamically adjusted according to the stability of the multi-frequency fusion phase; when the satellite signal is interrupted, the IMU drift correction coefficient is dynamically switched according to the satellite positioning accuracy in the last 3 seconds before the interruption to avoid high-error satellite data from contaminating the IMU calibration.

5. The centimeter-level positioning device for mapping and measurement with multi-frequency carrier phase smoothing according to claim 4 is characterized in that: The attitude adaptive tuning submodule also integrates a fan speed-vibration characteristic correlation unit: the real-time speed of the driving fan (11) is obtained through the speed sensor built into the fan connecting rod (10), and a mapping database of speed-vibration frequency / amplitude is established; when the speed change rate is >500rpm / s, the unit calls the matching vibration parameters in the database to perform "speed prediction compensation" on the phase data output by the high-speed analog-to-digital converter, rather than passively responding to vibration.

6. The centimeter-level positioning device for mapping and measurement with multi-frequency carrier phase smoothing according to claim 5 is characterized in that: The frequency point dynamic switching unit of the multi-frequency receiving antenna (13) is equipped with a polarization characteristic matching submodule. The polarization characteristic matching submodule pre-stores polarization characteristic parameters of L1 (right-hand circular polarization), L2 (right-hand circular polarization), and L5 (left-hand circular polarization). Combined with the UAV GPS position and three-dimensional terrain database, it identifies the material of the obstruction. Based on the reflection polarization attenuation law of different materials, it dynamically adjusts the frequency point switching threshold.

7. The centimeter-level positioning device for mapping and measurement with multi-frequency carrier phase smoothing according to claim 6 is characterized in that: The adaptive frequency point phase deviation calibration module also associates the slope factor of the survey area: it extracts the terrain slope of the current position of the UAV from the pre-installed three-dimensional terrain library. When the slope is greater than 30°, it automatically extends the historical data backtracking length of high signal-to-noise ratio frequency points from 10 cycles to 20 cycles and introduces the "slope-phase deviation amplification coefficient".

8. The centimeter-level positioning device for mapping and measurement with multi-frequency carrier phase smoothing according to claim 7 is characterized in that: The IMU inertial-assisted fusion unit is equipped with a temperature adaptive drift calibration submodule. The temperature adaptive drift calibration submodule introduces multi-frequency phase noise cross-validation: when the satellite signal is normal, the phase noise standard deviation of L1, L2 and L5 frequencies is calculated in real time. When the mean of the three is <0.05 weeks, the satellite positioning data of that period is used to perform "high-precision calibration" on the IMU temperature drift model; when the mean is >0.2 weeks, the calibration is paused and the most recent high-precision calibration result is used.

9. The centimeter-level positioning device for mapping and measurement with multi-frequency carrier phase smoothing according to claim 8 is characterized in that: The vibration adaptive phase compensation submodule is equipped with a multi-path reflection signal identification unit, which has the ability to classify reflection source types: by analyzing the spectral characteristics of the reflection signal, the reflection source is divided into three categories: ground, building, and water surface; for different types of reflection, the sliding window filtering parameters are dynamically adjusted, and the upper limit of the fusion weight is set accordingly.

10. The centimeter-level positioning device for mapping and measurement with multi-frequency carrier phase smoothing according to claim 9 is characterized in that: The frequency point dynamic switching unit is equipped with a satellite signal blockage prediction model. The satellite signal blockage prediction model introduces real-time ambient light intensity parameters: a light intensity sensor is installed on the top of the fuselage (1). When the light intensity is >50000 lux, the satellite signal receiving sensitivity will decrease by 15%-20%. The model incorporates this attenuation coefficient into the blockage probability calculation. When the light intensity is <5000 lux, the sensitivity is improved, and the blockage probability is corrected by multiplying the original calculated value by 0.8.

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