Radio frequency identification (RFID) rescue system based on luneberg lens antenna

Abstract

The invention relates to the technical field of emergency rescue, in particular to an RFID rescue system based on a Longbou lens antenna. The system comprises a read-write subsystem, a ground control system, an unmanned aerial vehicle and a passive radio frequency tag connected with a tag antenna, wherein the read-write subsystem comprises a luneberg lens antenna and a LoRa communication module which are respectively connected with a reader-writer module; and the read-write subsystem is arranged on the unmanned aerial vehicle, and the luneberg lens antenna is located 5-15 meters below the unmanned aerial vehicle. According to the invention, the transmission effect of the rescue signal is obviously improved, the rescue delay caused by signal interruption or weak signals is reduced, the stability and reliability of the rescue signal are obviously improved, the maintenance cost and complexity of equipment are greatly reduced, and the rescue efficiency and accuracy can be effectively improved. The method is wide in application range, and the scene can be expanded to a high-altitude mountainous area where the road condition is complex, the number of obstacles is large, and GPS satellite positioning has a signal blind area; the method is especially suitable for rescue scenes in extreme environments such as high altitude and avalanche.

Description

Technical Field

[0001] The present invention relates to the technical field of emergency rescue, and in particular to an RFID rescue system based on a Luneburg lens antenna. Background Art

[0002] In recent years, with the growing popularity of outdoor sports, participation in high-risk activities like mountaineering, skiing, and hiking has continued to grow globally. According to statistics, outdoor sports accidents kill over 1,000 people worldwide each year, with natural disasters like avalanches accounting for approximately 15%. Rescue efforts face particularly severe challenges, particularly in high-altitude and polar regions. In extreme outdoor environments like mountainous and snowy terrain, traditional communication equipment and rescue technologies often face numerous challenges: insufficient signal coverage, short transmission distances, inaccurate positioning, and poor device endurance in low-temperature environments, severely impacting rescue efficiency and success rates.

[0003] Current mainstream search and rescue methods include dog search, manual search, GPS positioning, satellite phone communications, and the Recco system. GPS and satellite phones rely on satellites deployed in space to function and utilize radio signals for information transmission. Satellite phones transmit and receive radio signals for voice and data communication. GPS receivers also receive radio signals from satellites to obtain positioning information. However, these technologies are susceptible to environmental influences and device battery depletion. In complex environments such as snowy mountains, signals are often interfered with by mountains, snow, and other natural obstacles, leading to communication interruptions. GPS and satellite phones, among other devices, cease functioning if their batteries run out. Manual search involves rescuers entering the disaster site and directly searching for trapped individuals through visual means. They conduct a rapid search for those trapped on the surface of debris or in easily accessible areas, and immediately rescue any individuals who are found and can be rescued. Dog search uses scent to locate trapped individuals. While these methods offer less environmental and equipment challenges, manual and dog search methods require significant manpower and resources, require specialized skills and physical fitness, and are time-consuming. The Recco system consists of a reflector and a detector. The detector emits a directional radar signal. When the signal strikes the Recco reflector, the reflector uses the signal energy to generate a frequency-doubled signal that is reflected back to the detector, allowing rescuers to locate the trapped person. While the device offers advantages such as being power-free, lightweight, portable, and maintenance-free, its detection range in avalanche scenarios is limited to 20-30 meters. Wearing only a single reflector is inaccurate and cannot provide specific location information.

[0004] Radio frequency identification and positioning technology has significant advantages in the field of emergency rescue due to its non-contact identification, multi-target identification, strong environmental adaptability, low cost, low power consumption, and the ability to quickly determine the target location. However, current radio frequency identification and positioning devices suffer from signal attenuation and poor penetration in extremely cold conditions, especially in sub-zero low-temperature environments such as snow-capped mountains and polar regions, making positioning difficult and implementation challenging.

[0005] Document 201610788808.X discloses a Beidou- and RFID-based positioning system and method. The positioning system includes an electronic tag device, an RFID reader / writer, a server, and a terminal device. The electronic tag device is an active RFID tag, comprising two batteries, an RFID chip, a Beidou chip, and an MCU. The positioning method involves sensing Beidou satellite signals and RFID signals, integrating and calculating them to output specific location coordinates. However, the following issues exist: 1. Because the RFID reader / writer uses an omnidirectional antenna with significantly low directivity, it is limited by antenna gain and transmit power, resulting in a short effective transmission range, a short recognition range, and insufficient positioning accuracy. 2. The electromagnetic waves emitted by the RFID reader / writer antenna operate at a high frequency (1.5 / 2.4 GHz), making them sensitive to environmental factors such as humidity and electromagnetic interference, thus impacting the reliability of rescue operations. 3. Due to the low antenna gain and the relatively high frequency (1.5 / 2.4 GHz) of the electromagnetic waves emitted by the antenna, the measured positioning error can exceed 5 meters at disaster sites with uneven snow cover and significant multipath effects, making it impossible to accurately locate the coordinates of trapped individuals, thus affecting rescue efficiency. 4. Active RFID is bulky and inconvenient to carry. It also relies on external power supply and is expensive.

[0006] 201710699607.7 discloses an all-weather vehicle positioning system based on RFID and satellite positioning technology, including a housing, an RFID transceiver system, a GPS positioning system, and a central data processing system. The RFID transceiver system is divided into an on-board portion and a municipal construction portion. The on-board portion is an electronic tag, which includes an antenna, a radio frequency module, a power supply, a storage device, and a control module; the municipal construction portion is a power supply, a radio frequency module, an antenna, and a reader / writer module. The GPS positioning system includes a GPS signal transceiver, which is installed on the vehicle, and a GPS satellite terminal, which is installed on the satellite. The problems are: 1. Because the RFID reader / writer system uses a low-gain antenna, the recognition distance is generally short; 2. Because the GPS positioning system used in this invention includes a GPS signal transceiver, it has the disadvantages of complex positioning system design, high cost, and large size; 3. The positioning system proposed in this invention is only applicable to urban transportation with relatively open and flat road conditions, and is not suitable for sub-zero low-temperature environments such as snow-capped mountains and polar regions. Summary of the Invention

[0007] The present invention proposes an RFID rescue system based on Luneburg lens antenna to solve the technical problems existing in the prior art, such as short recognition distance, insufficient positioning accuracy, signal attenuation in extreme cold conditions, weak penetration ability, great difficulty in positioning, and difficult implementation.

[0008] In order to achieve the above-mentioned purpose, the technical solution adopted by the present invention is: an RFID rescue system based on a Luneburg lens antenna, including a reading and writing subsystem, a ground control system, a drone and a passive radio frequency tag connected to a tag antenna, the reading and writing subsystem includes a Luneburg lens antenna and a LoRa communication module respectively connected to the reader / writer module; the reading and writing subsystem is arranged on the drone, and the Luneburg lens antenna is located 5-15 meters below the drone.

[0009] Furthermore, the signal transmitted by the above-mentioned Luneburg lens antenna is a UHF signal with a frequency range of 490-860 MHz.

[0010] Furthermore, the above-mentioned drone has functions such as automatic flight, route planning, fixed-altitude flight, fixed-point flight, automatic return, automatic obstacle avoidance, automatic identification, tracking flight and endurance.

[0011] Compared with the prior art, the present invention has the following beneficial effects:

[0012] 1. The present invention adopts Luneburg lens as the transmitting antenna, achieving stable signal coverage of more than 80 meters, and the detection distance is increased by more than 3 times compared with the traditional Recco reflector (coverage range of only 20-30 meters). At the same time, the Luneburg lens antenna is located 5-15 meters below the drone, closer to the ground, with greater intensity, more stable signal reception, stronger ability to cross obstacles, and higher detection accuracy. This application not only significantly expands the signal coverage range, but also greatly enhances the effective transmission distance of the rescue signal, enabling rescue personnel to receive distress signals in a wider area in a timely manner, effectively shortening the rescue response time. The application scenarios of the rescue positioning system designed by the present invention can be expanded to high-altitude mountainous areas with complex road conditions, many obstacles, and signal blind spots in GPS satellite positioning.

[0013] 2. In extreme outdoor environments, such as snow and mountainous terrain, the impact of natural factors on rescue signal transmission is particularly pronounced. Snow significantly interferes with the transmission of high-frequency signals, especially millimeter-wave radar signals, whose scattering rate can reach over 30%. This significantly reduces signal strength and positioning accuracy, making it difficult for rescue equipment to accurately obtain the location of trapped individuals, increasing the difficulty and time cost of rescue operations. Furthermore, the complex terrain of mountainous areas can cause radio frequency signals to be blocked by natural obstacles such as mountains and vegetation, creating coverage blind spots, further hindering the smooth implementation of rescue operations. Furthermore, complex environments can lead to unstable signal transmission paths and intermittent signals, increasing the complexity and uncertainty of rescue operations. To effectively address these issues, the Luneburg lens antenna of the present invention transmits UHF signals in the frequency range of 490-860 MHz. Compared to millimeter-wave signals, UHF signals have excellent penetration capabilities through soil, rocks, and snow. Even when obstructed by mountains, vegetation, and snow, they can quickly penetrate, effectively ensuring the received signal strength and communication stability of the rescue system. This technological breakthrough significantly improves the transmission effect of rescue signals in complex environments, reduces rescue delays caused by signal interruption or weak signals, and ensures the timeliness and effectiveness of rescue operations. In addition, the penetration ability of UHF signals also provides strong support for multi-target positioning. In complex outdoor environments, trapped persons may be distributed in different locations, and the surrounding environment is complex. UHF signals can penetrate a variety of obstacles, enabling the rescue system to receive signals from multiple targets at the same time, achieving more accurate multi-target positioning, and further improving rescue efficiency. The application of this technology provides strong support for rescue work in extreme outdoor environments, significantly improves the stability and reliability of rescue signals, and ensures the smooth progress of rescue operations. By adopting UHF signals of specific frequencies, the present invention significantly improves the performance of the rescue system in extreme environments such as snow and mountains, providing a more reliable solution for safety assurance and emergency rescue in outdoor sports.

[0014] 3. In emergency situations where multiple trapped people need rescue at the same time, the misjudgment rate of traditional radio frequency rescue systems can be as high as 15%. The present invention uses passive radio frequency tag technology. The radio frequency tag carried by the rescue target is a passive structure, which has the advantages of not requiring a power source and being lightweight and easy to carry. This passive radio frequency tag communicates with the rescue equipment through reflection modulation and can operate normally even without an external power source. In the case of multiple targets calling for help at the same time, the present invention can quickly distinguish and identify the source of each signal, reducing the misjudgment rate to a minimum. In addition, the system also has the ability to quickly locate and track in real time, and can quickly determine the location of trapped people in complex environments, significantly improving rescue efficiency and success rate. The application of this passive radio frequency tag technology not only solves the shortcomings of traditional radio frequency rescue systems in multi-target identification, but also provides a more efficient and accurate solution for complex rescue scenarios. By adopting passive radio frequency tags, the rescue system of the present invention performs well in multi-target identification and positioning, significantly improving anti-interference ability and positioning accuracy, and providing strong technical support for the safety of outdoor sports and large-scale events.

[0015] 4. When performing outdoor rescue missions, the radio frequency tag carried by the rescue target adopts a passive structure, which has the advantages of not requiring a power source and being light and easy to carry. This feature not only makes the rescue equipment more convenient to use and easy to be carried by various rescue targets, but also ensures the continuous and stable transmission of rescue signals in extreme environments such as rainstorms, heavy snow or earthquakes, greatly improving the efficiency and success rate of rescue. The passive radio frequency tag technology used in the present invention does not rely on an external power source and can work as long as there is a signal excitation, which greatly reduces the maintenance cost and complexity of the equipment, and also reduces the training requirements for rescue personnel in the use of the equipment. Its lightweight feature is suitable for various rescue scenarios, and can be easily deployed in complex terrains such as mountains, oceans or dense forests, playing a key role in expanding the scope of rescue and speeding up the rescue.

[0016] 5. The system of the present invention boasts a longer transmission distance, capable of covering a wider area of ​​the ocean surface, ensuring stable signal transmission during long-distance search and rescue missions. Furthermore, the system's enhanced signal penetration enables precise positioning and real-time communication even in harsh ocean environments or with complex obstacles. Therefore, the intelligent rescue system proposed in this invention can be extended to target search and rescue operations at sea, possessing a wide range of applications. It can significantly improve the efficiency and success rate of maritime rescue operations, providing a more reliable guarantee for maritime safety.

[0017] 6. The intelligent rescue system proposed in the present invention achieves a significant reduction in rescue response time by organically combining radio frequency identification technology, high-precision positioning technology in drone flight control systems, and LoRa point-to-point communication technology. The system uses LoRa point-to-point communication technology to realize data backhaul between the sky end and the ground end, and can quickly and accurately obtain the tag information and location information carried by the trapped person. This combination of technologies not only solves the problem of long startup time of traditional rescue equipment, but also reduces time delays caused by users' unskilled operation through automation and intelligent means. In addition, the design cost of the system is significantly reduced and deployment is convenient. It is particularly suitable for scenarios in extreme environments such as high altitudes and avalanches where signal transmission at the rescue site is limited and traditional communication means are limited or ineffective. The application of this technology not only improves rescue efficiency, but also provides an efficient and reliable long-distance intelligent rescue solution for the field of outdoor sports rescue.

[0018] 7. The present invention introduces drone technology, which provides a new approach to solving the problem of insufficient signal coverage. Drones can carry communication equipment and fly over the disaster-stricken area, expanding the signal transmission and reception area, and realizing the identification and positioning of rescue targets in a wider range. It is particularly suitable for complex terrain or large-scale disaster scenes. In addition, drones can also serve as "air relay stations", equipped with LTE private network communication equipment to extend the signal transmission distance, or realize beyond-line-of-sight data transmission through laser communication, solving the "last mile" communication problem. In summary, by combining drone technology with intelligent rescue systems, the efficiency and accuracy of rescue can be significantly improved. This technical application provides an efficient and reliable solution for emergency rescue, and is particularly suitable for rescue scenarios in extreme environments such as high altitudes and avalanches. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a structural schematic diagram of the present invention. DETAILED DESCRIPTION

[0020] The present invention is described in further detail below with reference to the accompanying drawings and embodiments.

[0021] The present invention provides an RFID rescue system based on a Luneburg lens antenna, comprising a read / write subsystem, a ground control system, an unmanned aerial vehicle (UAV), and a passive radio frequency tag connected to a tag antenna. The read / write subsystem includes a Luneburg lens antenna and a LoRa communication module, each connected to a reader / writer module. The read / write subsystem is mounted on the UAV, with the Luneburg lens antenna positioned 10 meters below the UAV. The signal transmitted by the Luneburg lens antenna is a UHF signal with a frequency range of 490-860 MHz. The UAV has functions such as automatic flight, route planning, fixed-altitude flight, fixed-point flight, automatic return, automatic obstacle avoidance, automatic identification, tracking flight, and endurance. Positioning is achieved using GPS or Beidou satellites.

[0022] The rescued target carries a passive radio frequency tag with a tag antenna. The rescue system of the present invention can be divided into a sky end and a ground end as a whole. The sky end is mainly composed of an emergency rescue drone and a reading and writing subsystem carried by the drone, which is mainly used for ground scanning flight to achieve fast and efficient large-area aerial search and perception and identification of radio frequency tags. The ground end is mainly composed of a passive radio frequency tag and a ground control system. The passive radio frequency tag is equipped with a tag antenna, and the tag stores a unique identification code and relevant information of the corresponding target. The ground control system receives the data sent by the sky end, processes it and presents the coordinates of the rescued target, the drone and the ground control system in real time.

[0023] Based on the provided system, the specific implementation process of the present invention is as follows:

[0024] First, the Luneburg lens antenna serves as the transmitting antenna for the read / write subsystem, emitting ultrahigh frequency (UHF) electromagnetic waves in the 490-860 MHz frequency range. When this UHF signal detects the passive RFID tag carried by the target, it generates electromagnetic induction. The induced electromagnetic wave is transmitted via the tag antenna to the Luneburg lens antenna in the sky-side read / write subsystem, which then transmits the tag's stored information to the read / write subsystem. Simultaneously, the drone locates the target carrying the RFID tag. The drone's positioning information and the tag data analyzed by the read / write subsystem are then transmitted to the LoRa communication module. The LoRa communication module then transmits the target's tag and location information back to the ground control system via point-to-point communication technology. The module accurately calculates and records the target's tag information and latitude and longitude location. The ground control system then transmits this information to the rescue command center, enabling rapid and accurate rescue of the target.

[0025] The above description is an explanation of the specific implementation of the present invention, rather than a limitation of the present invention. Those skilled in the relevant technical field can also make various equivalent technical solutions without departing from the scope of the present invention, so all equivalent technical solutions should be included in the scope of protection of the present invention.

Claims

1. An RFID rescue system based on a Luneburg lens antenna, characterized by: It includes a reading and writing subsystem, a ground control system, a drone and a passive radio frequency tag connected to a tag antenna. The reading and writing subsystem includes a Luneburg lens antenna and a LoRa communication module respectively connected to the reader / writer module; the reading and writing subsystem is set on the drone, and the Luneburg lens antenna is located 5-15 meters below the drone.

2. The RFID rescue system based on Luneburg lens antenna according to claim 1, characterized in that: The signal transmitted by the Luneburg lens antenna is a UHF signal with a frequency range of 490-860 MHz.

3. The RFID rescue system based on Luneburg lens antenna according to claim 1 or 2, characterized in that: The UAV has the functions of automatic flight, route planning, fixed-altitude flight, fixed-point flight, automatic return, automatic obstacle avoidance, automatic identification, tracking flight and endurance.

Images