Unmanned aerial vehicle accurate positioning system based on UWB technology

Abstract

The utility model discloses an unmanned aerial vehicle accurate positioning system based on a UWB technology. The system comprises a UWB positioning label, a positioning base station and an unmanned aerial vehicle. The positioning base station is composed of a circular circuit board, four patch antennas and a high-performance UWB chip, an upper patch, a lower patch, a left patch and a right patch form two groups of antennas respectively, and each group of antennas is connected with an independent UWB chip. When the system works, the base station sends a signal to the UWB tag and receives a reflected signal, the distance is accurately measured through a time of flight (ToF) method, meanwhile, the phase difference of signals received by the same group of antennas is calculated through the interferometer principle, an incoming wave azimuth angle and an incoming wave elevation angle are obtained, and three-dimensional space centimeter-level positioning is achieved. The UWB signal has nanosecond-level time resolution and strong multipath interference resistance, and can still maintain stable communication in a complex environment. And the unmanned aerial vehicle adjusts the flight path in real time according to the position data resolved by the base station.

Description

Technical Field

[0001] This utility model provides a positioning system, belonging to the field of unmanned aerial vehicle (UAV) control and navigation technology, and particularly relates to a UAV precision positioning system based on UWB technology. Background Technology

[0002] A drone is an unmanned aircraft that is managed by a remote control station or controlled by autonomous flight. The significance of its positioning lies in achieving autonomous navigation and precise control, ensuring the safe flight and mission execution of drones in complex environments, such as playing an important role in disaster relief, agricultural plant protection, and geological exploration. At the same time, the development of positioning technology has also promoted the application of drones in more scenarios and the improvement of their intelligence level.

[0003] Existing drone positioning systems suffer from low accuracy in complex environments, especially in high-rise buildings or indoor settings. Traditional GPS signals are easily affected by building obstruction and multipath interference, resulting in positioning errors typically exceeding 1 meter, which fails to meet the demands of precise operations. Visual positioning relies on ambient lighting conditions and is prone to failure in low-light or smoky environments. While lidar can achieve centimeter-level positioning, its high hardware cost and susceptibility to error accumulation on complex reflective surfaces (such as glass curtain walls) severely limit the application of drones in logistics delivery, warehouse management, and indoor inspection. Therefore, a high-precision, highly interference-resistant, and low-cost drone positioning system is urgently needed. Utility Model Content

[0004] In order to overcome the shortcomings of the prior art, this application provides a UAV precision positioning system based on UWB technology, which solves the problems of low positioning accuracy, signal blockage and unstable positioning caused by multipath effects in complex environments.

[0005] To solve the above-mentioned technical problems, this utility model provides the following technical solution: a UWB-based UAV precise positioning system, comprising: a UWB positioning tag, a positioning base station, a high-performance UWB chip, and a UAV;

[0006] The UWB positioning tag is used to receive and reflect UWB positioning signals;

[0007] The positioning base station includes a circular circuit board, four patch antennas, and a high-performance UWB chip.

[0008] The patch antennas are respectively the upper and lower patches and the left and right patches fixed to the circular circuit board, wherein the upper and lower patches (2) constitute the first group of antennas and the left and right patches constitute the second group of antennas, and the baselines of the two groups of antennas are distributed in a cross shape.

[0009] The high-performance UWB chip is connected to each patch antenna group for:

[0010] The distance between the positioning base station and the UWB positioning tag is measured using the time-of-flight method.

[0011] The phase difference of the received signals from the same group of patch antennas is calculated based on the interferometer principle to obtain the azimuth and elevation angles of the incoming wave.

[0012] The UAV is communicatively connected to the positioning base station and is used to generate flight control commands based on the three-dimensional position data calculated by the positioning base station to adjust its flight trajectory.

[0013] Preferably, the positioning base station is mounted on the UAV body, forming an integrated positioning and flight control module.

[0014] Preferably, the patch antenna and the high-performance UWB chip are integrated and packaged inside the circular circuit board, and the real-time signal processing response time of the high-performance UWB chip is less than 10 milliseconds.

[0015] Preferably, the length of the patch antenna baseline satisfies:

[0016]

[0017] To avoid direction finding errors caused by phase ambiguity.

[0018] Preferably, the UAV receives real-time location data transmitted by the positioning base station through a wireless communication module, and generates flight control commands based on the data to adjust its heading and altitude.

[0019] One or more technical solutions provided in the embodiments of this application have at least the following technical effects or advantages:

[0020] This utility model system has three significant advantages: high-precision positioning, strong anti-interference capability, and low cost and easy deployment. First, it achieves nanosecond-level time measurement through UWB technology, resulting in positioning accuracy significantly higher than traditional GPS technology, making it particularly suitable for precise positioning in complex environments. Second, thanks to the strong penetration capability and anti-multipath effect capability of UWB signals, the system can maintain stable signal transmission even in complex environments. In addition, compared with lidar or visual positioning systems, this system has lower hardware costs, and the positioning tags are battery-powered, facilitating flexible deployment and mobility.

[0021] Other advantages, objectives and features of this invention will be set forth in part in the description which follows, and in part will be apparent to those skilled in the art from the following examination or study, or may be taught from the practice of this invention. Attached Figure Description

[0022] Figure 1This invention relates to the main structure of a UAV precision positioning system based on UWB technology.

[0023] Figure 2 This is a flowchart of a UAV precise positioning system based on UWB technology according to this utility model;

[0024] Figure 3 This is a schematic diagram of the interferometer direction finding principle of a UAV precision positioning system based on UWB technology.

[0025] As shown in the figure:

[0026] 1. Circular circuit board; 2. Top and bottom surface mount components; 3. Left and right surface mount components. Detailed Implementation

[0027] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0028] It should be noted that the terms "vertical," "horizontal," "up," "down," "left," "right," and similar expressions used in this article are for illustrative purposes only and do not represent the only possible implementation.

[0029] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains; the terminology used herein in the description of this invention is for the purpose of describing particular embodiments only and is not intended to limit the invention; the term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0030] like Figure 1 and Figure 2 As shown, a UAV precision positioning system based on UWB technology mainly includes a UWB positioning tag, a positioning base station, a high-performance UWB chip, and a UAV. The UWB positioning tag is used to receive and reflect UWB positioning signals. The positioning base station consists of a circular circuit board, four patch antennas (top and bottom patches and left and right patches, divided into two groups with a cross-shaped baseline), and a high-performance UWB chip. The chip connects to each group of antennas. The distance between the positioning base station and the tag is measured using the time-of-flight method, and the phase difference of the received signals from the same group of antennas is calculated based on the interferometer principle to obtain the azimuth and elevation angles of the incoming wave. The UAV communicates with the positioning base station and generates flight control commands based on the three-dimensional position data calculated by the positioning base station to adjust its flight trajectory.

[0031] In this embodiment, the UAV precise positioning system of this utility model includes a positioning tag, a base station, and a UAV. The positioning tag receives and transmits UWB signals through an ultra-wideband transceiver and an antenna; the UAV carries a base station, receives location data, calculates the positioning result, and generates flight control commands.

[0032] The base station is a core component of this system, primarily responsible for transmitting and receiving signals, positioning, and measuring signal transmission time and phase difference to achieve high-precision positioning. The base station is equipped with four patch antennas located at the top, bottom, left, and right of the circular disk. The top and bottom antennas form one group, and the left and right antennas form another group, with their baselines forming a cross structure. This design effectively measures the phase difference of signals arriving in different directions, thereby accurately calculating the azimuth and elevation angles of the signals, significantly improving the system's direction-finding resolution, especially suitable for applications requiring high-precision direction measurement. The positioning tag is battery-powered, facilitating flexible deployment and mobility. In practical applications, the effective ranging and communication distance of the positioning tag's UWB signal is within tens of meters, suitable for precise positioning scenarios. Even in complex environments, the UWB signal maintains stable transmission performance. The drone carries the base station. The base station is used to transmit and receive UWB positioning signals and communicate with the positioning tag. The base station incorporates a high-performance UWB chip, supporting high-speed signal processing to ensure the real-time performance and accuracy of the positioning signal. After receiving the UWB signal from the positioning tag, the base station uses high-precision ranging and direction finding algorithms to calculate the UAV's position data; after receiving the transmitted position data, the UAV generates flight control commands.

[0033] It needs to be emphasized and explained that,

[0034] Ranging is based on the Time-of-Flight (ToF) method, which reduces time synchronization requirements and improves ranging accuracy by measuring the transmission time of the signal between the base station and the positioning tag. The time it takes for the UWB signal to travel from the base station to the positioning tag is T. a The time it takes for the location tag to receive a UWB signal and reflect it back to the base station is T. b Use the formula:

[0035]

[0036] The distance d between the base station and the positioning tag is calculated. Where T... a T is the transmission time of the UWB signal from the base station to the tag. b is the transmission time of the UWB signal reflected from the positioning tag back to the base station, and c is the speed of light.

[0037] Direction finding uses a phase interferometer-based method, determining the angle of arrival (AoA) of a signal by measuring the phase difference between the signals arriving at different antennas. For example... Figure 3As shown, according to the direction-finding formula of a phase interferometer:

[0038]

[0039] The wave azimuth angle θ is calculated. Wherein, Let λ represent the phase difference of the signals received by the same set of antennas, D be the baseline length of the patch antenna, and λ be the wavelength of the UWB signal. To prevent phase ambiguity, ... Based on the two sets of incoming wave azimuth angles α1 and α2 obtained from the two sets of baselines, the azimuth and elevation angles between the base station and the positioning tag are calculated, thereby achieving high-precision direction finding in three-dimensional space. This method is also significantly superior to traditional single-direction direction finding algorithms.

[0040] like Figure 2 and Figure 3 As shown, a UAV precision positioning system based on UWB technology integrates a positioning base station mounted on the UAV fuselage, forming a unified positioning and flight control module. The UWB positioning tag has an effective ranging and communication range of tens of meters, adapting to complex environments. A patch antenna and a high-performance UWB chip are integrated and packaged within a circular circuit board, with the chip's real-time signal processing response time being less than 10 milliseconds. The patch antenna has a reasonable baseline length to avoid direction-finding errors caused by phase ambiguity. The UAV receives real-time position data transmitted from the positioning base station via a wireless communication module, generates flight control commands accordingly, and adjusts its heading and altitude to achieve precise positioning and flight control.

[0041] In this implementation plan, the connection relationships and positional layout of the various components are as follows:

[0042] 1. Hardware integration relationship: Positioning base stations can be installed in different locations according to different application requirements.

[0043] The core component inside the base station is a circular circuit board with four patch antennas (two groups, one on top and one on the left and right) symmetrically distributed on its surface with a cross-shaped baseline. Each group of antennas is directly connected to an independent high-performance UWB chip. The chip and antennas are integrated inside the circuit board through microstrip lines to achieve direct physical layer connection for signal transmission, reception and processing.

[0044] 2. Signal Link Design: UWB positioning tags are deployed in the target area and communicate bidirectionally with the base station through an omnidirectional antenna; after the four patch antennas of the base station receive the reflected signals from the tags, they are transmitted to the corresponding UWB chips for real-time processing, and finally the main control module fuses multiple sets of data to generate three-dimensional coordinates; the UAV's built-in wireless communication module (such as WiFi or 4G) is directly connected to the base station data interface to achieve low-latency transmission of positioning results.

[0045] Key implementation points and the beneficial effects of innovation include:

[0046] 1. Structural optimization and precision improvement:

[0047] The cross-shaped patch antenna baselines, through orthogonal phase difference measurement, significantly improve the calculation accuracy of azimuth and elevation angles, avoiding the directional ambiguity problem of single-baseline interferometers;

[0048] The antenna baseline length is strictly limited to By combining the characteristics of UWB broadband signals, phase periodic ambiguity is effectively suppressed, ensuring direction finding stability in complex environments.

[0049] 2. Enhanced real-time performance and reliability:

[0050] The high-performance UWB chip and antenna are integrated into a single package design, which shortens the signal transmission path. Combined with a parallel processing architecture (each antenna operates independently), the response time is compressed to less than 10 milliseconds, meeting the high-speed flight control requirements of UAVs.

[0051] The nanosecond-level pulses and high time resolution of UWB signals enable Time-of-Flight (ToF) ranging errors to be less than 5 centimeters, far exceeding the accuracy of traditional GPS.

[0052] 3. Cost and deployment advantages:

[0053] Compared to LiDAR solutions that rely on multi-sensor fusion, this system achieves full-function positioning through a single UWB technology, reducing hardware costs by more than 60%.

[0054] The positioning tags are powered by low-power batteries, support instant deployment without the need for wiring or fixed power supply, and are particularly suitable for rapid deployment in dynamic scenarios such as warehouse shelves and disaster sites.

[0055] Through a heterogeneous architecture of "cross antenna + dual UWB chips", the system achieves centimeter-level positioning in three-dimensional space with limited hardware scale, while taking into account anti-interference, low cost and easy deployment, providing reliable technical support for the precise operation of UAVs in complex environments.

[0056] In one feasible embodiment

[0057] In logistics and delivery scenarios, drones need to achieve precise positioning in complex environments (such as densely populated areas of high-rise buildings or indoor warehouses).

[0058] Implementation steps:

[0059] Positioning tags are deployed near the target location to ensure accurate positioning within the UWB signal coverage area. After the drone takes off, the positioning base station sends a UWB positioning signal. The positioning tag receives the UWB signal and reflects it back to the base station. The base station uses a UWB chip to calculate the location data, and the drone flies to the target location based on the positioning data.

[0060] In operation, UWB positioning tags are first deployed in the target area to ensure their coverage matches the drone's operating area. The drone and its onboard positioning base station are then activated. The base station sends nanosecond-level UWB pulse signals to the tags, which receive and reflect the signals to the base station's cross-shaped patch antenna array. The high-performance UWB chip within the base station calculates the round-trip time difference of the signal using the time-of-flight method, precisely determining the distance between the drone and the tags in real time. Simultaneously, it analyzes the phase difference of signals received by the same set of antennas based on interferometry principles, combined with baseline length limitations. The system eliminates phase ambiguity and obtains the azimuth and elevation angles of the incoming wave. Subsequently, the chip fuses the distance and angle data to generate three-dimensional coordinates, which are transmitted to the UAV flight control system via a wireless communication module. The UAV dynamically adjusts its heading, altitude, and flight speed based on the real-time positioning results, such as accurately hovering at a designated location on a shelf in a logistics scenario or avoiding obstacles in a complex environment. After completing the mission, the UAV can return autonomously, and the positioning tag can be recycled or the battery can be replaced to adapt to new mission requirements. The entire system achieves centimeter-level positioning accuracy and 10-millisecond-level response efficiency through the high penetration and anti-multipath characteristics of UWB signals and hardware integration design, making it suitable for rapid deployment and stable operation in scenarios such as warehouse inspection and emergency rescue.

[0061] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be determined by the claims.

Claims

1. A precise positioning system for unmanned aerial vehicles (UAVs) based on UWB technology, characterized in that, include: UWB positioning tags, positioning base stations, high-performance UWB chips, and drones; The UWB positioning tag is used to receive and reflect UWB positioning signals; The positioning base station includes a circular circuit board (1), four patch antennas, and a high-performance UWB chip; The patch antennas are respectively the upper and lower patches (2) and the left and right patches (3) fixed to the circular circuit board (1), wherein the upper and lower patches (2) constitute the first group of antennas and the left and right patches (3) constitute the second group of antennas, and the baselines of the two groups of antennas are distributed in a cross shape. The high-performance UWB chip is connected to each patch antenna group for: The distance between the positioning base station and the UWB positioning tag is measured using the time-of-flight method. The phase difference of the received signals from the same group of patch antennas is calculated based on the interferometer principle to obtain the azimuth and elevation angles of the incoming wave. The UAV is communicatively connected to the positioning base station and is used to generate flight control commands based on the three-dimensional position data calculated by the positioning base station to adjust its flight trajectory.

2. The UAV precise positioning system based on UWB technology according to claim 1, characterized in that: The positioning base station is mounted on the UAV body, forming an integrated positioning and flight control module.

3. The UAV precise positioning system based on UWB technology according to claim 1, characterized in that: The patch antenna and the high-performance UWB chip are integrated and packaged inside the circular circuit board (1), and the real-time signal processing response time of the high-performance UWB chip is less than 10 milliseconds.

4. The UAV precise positioning system based on UWB technology according to claim 1, characterized in that: The length of the patch antenna baseline satisfies: To avoid direction finding errors caused by phase ambiguity.

5. A UAV precise positioning system based on UWB technology according to claim 1, characterized in that: The UAV receives real-time location data transmitted by the positioning base station through a wireless communication module, and generates flight control commands based on the data to adjust its heading and altitude.

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