CN-121995313-A - Spin scanning direction finding and cross positioning method based on single unmanned aerial vehicle platform

CN121995313ACN 121995313 ACN121995313 ACN 121995313ACN-121995313-A

Abstract

The invention discloses a spin scanning direction finding and cross positioning method based on a single unmanned plane platform, and relates to a radio positioning technology. The method comprises the steps of controlling an unmanned aerial vehicle carrying a directional antenna to hover at a first measuring point and spin around an axis, synchronously collecting Received Signal Strength (RSSI) and yaw angle, obtaining a first azimuth angle of a radiation source by detecting an RSSI peak value, then enabling the unmanned aerial vehicle to fly to a second measuring point, repeating the process to obtain a second azimuth angle, and finally utilizing a cross positioning source to understand and calculate the coordinates of the radiation source according to the coordinates and the azimuth angles of the measuring points. The invention realizes the mechanical scanning of the antenna by using the spin of the unmanned aerial vehicle, realizes the single-station multipoint direction finding and positioning by using extremely simple hardware (single antenna), has the advantages of low cost, quick deployment and easy integration, and is suitable for quickly searching and positioning the ground fixed radiation source.

Inventors

XIAN BING
Xue Xincheng
LIN JIANLONG

Assignees

福州慧识科技有限公司

Dates

Publication Date: 20260508
Application Date: 20260227

Claims (8)

1. A spin scanning direction finding and crossing positioning method based on a single unmanned aerial vehicle platform is characterized by being carried out by an unmanned aerial vehicle platform carrying a directional antenna, a radio frequency signal acquisition unit, a navigation and attitude measurement unit and a main control and processing unit, and comprises the following steps of S1, controlling the unmanned aerial vehicle to fly to a first measurement point and hover, S2, controlling the unmanned aerial vehicle to spin around a vertical axis of the unmanned aerial vehicle at a constant angular velocity, driving the directional antenna carrying the unmanned aerial vehicle to carry out horizontal mechanical scanning, synchronously acquiring Received Signal Strength (RSSI) data and real-time yaw angle data of the unmanned aerial vehicle, S3, detecting a peak value of the RSSI according to the corresponding relation between the RSSI data and the yaw angle data acquired in one or more spin periods, and recording a real-time yaw angle corresponding to the peak value as a first azimuth angle measured value of a radiation source at the first measurement point, S4, controlling the unmanned aerial vehicle to fly to at least one second measurement point, repeating steps S2-S3, obtaining a second azimuth angle measured value of the radiation source at the second measurement point, and calculating a radiation azimuth angle measured value based on the first coordinate and a corresponding coordinate position of the first coordinate measured value and a corresponding coordinate position of the radiation source.
2. The method according to claim 1, characterized in that in step S3, the RSSI data is processed by smoothing and the yaw angle corresponding to the peak is determined by peak detection of the RSSI-yaw angle curve or peak time detection of the curve of the RSSI over time and matching with the synchronously recorded yaw angle time stamps.
3. The method of claim 1, wherein in step S5, the solving uses a least squares estimation method to minimize the sum of squares of the vertical distances of the radiation source coordinate estimation point to each azimuth line determined by the measurement point coordinates and the azimuth angle measurements.
4. The method according to claim 1, characterized in that in steps S1 and S4 the first measuring point and the second measuring point are selected such that the angle between the azimuth lines measured on the basis of both is approximately 90 degrees.
5. The method of claim 1, wherein the horizontal 3dB beamwidth of the unmanned aerial vehicle-mounted directional antenna is 20 degrees to 40 degrees.
6. The method of claim 5, wherein the horizontal 3dB beamwidth of the directional antenna is 30 degrees.
7. The method according to claim 1, characterized in that in step S2 the drone is controlled to spin at a constant speed at an angular speed of 3 to 12 degrees/sec.
8. A computer readable storage medium, having stored thereon a computer program, which when executed by a processor is adapted to control a drone platform to carry out the method according to any one of claims 1 to 7.

Description

Spin scanning direction finding and cross positioning method based on single unmanned aerial vehicle platform Technical Field The invention relates to the technical field of radio positioning and unmanned aerial vehicle application, in particular to a method for realizing single-station multipoint direction finding and cross positioning of a radiation source target by utilizing a single unmanned aerial vehicle to drive a directional antenna to scan through spin movement. Background In the tasks of spectrum management, emergency search and rescue (positioning of emergency position indicating beacons), illegal radio signal tracing and the like, quick and accurate positioning of an unknown radiation source is important. Traditional mainstream techniques include multi-station arrival time difference/frequency difference positioning and single-station array direction finding positioning. The former requires the deployment of receiving stations at multiple locations, the system is complex, costly, slow to deploy, while the latter, while single-station, typically relies on expensive multi-antenna arrays and complex digital beam forming processing equipment, which are not suitable for miniaturized, low-cost unmanned aerial vehicle platforms in terms of volume, power consumption, and cost. The unmanned aerial vehicle is used as a highly mobile air platform, and an ideal carrier is provided for flexible and rapid radiation source positioning. However, existing drone-based positioning schemes still mostly rely on multiple physical antennas or require that the signals have cooperative characteristics (e.g., known modulation formats). Therefore, there is an urgent need for a lightweight radiation source positioning method with extremely simple hardware configuration, suitable for small single unmanned aerial vehicle platforms. Disclosure of Invention The invention aims to overcome the defects of the prior art and provides a spin scanning direction finding and cross positioning method based on a single unmanned plane platform. According to the method, accurate direction finding is achieved through mechanical scanning by only utilizing the rotation capability of a pair of conventional directional antennas and the unmanned aerial vehicle, geometric intersection positioning is conducted by combining position movement of the unmanned aerial vehicle, and reliable positioning under extremely simple hardware configuration is achieved. The spin scanning direction finding and cross positioning method based on the single unmanned aerial vehicle platform is carried out by the unmanned aerial vehicle platform with the directional antenna, the radio frequency signal acquisition unit, the navigation and gesture measurement unit and the main control and processing unit, and comprises the following steps of firstly controlling the unmanned aerial vehicle to fly to a first measurement point and hover. Subsequently, the drone is controlled to spin at a constant angular velocity about its vertical axis (yaw axis), this motion driving the directional antenna on which it is mounted to mechanically scan in a horizontal plane. In the process, the Received Signal Strength (RSSI) data from the radio frequency signal acquisition unit and the unmanned aerial vehicle real-time yaw angle data from the navigation and attitude measurement unit are synchronously and high-speed acquired. And then, analyzing the corresponding relation between the RSSI and the yaw angle according to the data acquired in one or more complete spin periods, and detecting the peak point of the RSSI. The real-time yaw angle corresponding to the peak point characterizes that the maximum gain direction of the main lobe of the antenna is aligned with the radiation source at the moment, so that a first azimuth angle measured value of the radiation source at a first measuring point is obtained. And then, controlling the unmanned aerial vehicle to fly to at least one second measuring point, and repeating the spin scanning and peak value detection steps to obtain a second azimuth angle measured value. Finally, based on the accurate geographic coordinates of each measuring point and the corresponding azimuth angle measured value, the geographic coordinate estimated value of the radiation source is calculated by utilizing the geometrical principle of direction finding and cross positioning. Preferably, the horizontal 3dB beamwidth of the directional antenna is 20 to 40 degrees, preferably 30 degrees. This width provides better azimuth resolution while ensuring adequate signal acquisition probability and scanning efficiency. Preferably, during the direction finding process, the RSSI data is smoothed to suppress noise, and a peak detection algorithm is adopted to accurately determine the yaw angle corresponding to the peak. Preferably, in the positioning calculation step, a least square estimation algorithm is adopted to process the situation that a plurality of azimuth lines possibly ca