49results about How to "Realize ranging" patented technology

The invention provides a laser radar light path system which is used in the field of laser radar ranging. The system comprises a transmitting system body and a receiving system body. The transmitting system body is used for transmitting laser signals to target objects; the receiving system body is used for receiving laser echo signals reflected from the target objects, and comprises a main receiving lens used for focusing the first laser echo signals reflected from the target objects, a compensating mirror and a photoelectric detector, wherein the compensating mirror is arranged on the main receiving lens and used for compensating the second laser echo signals reflected from the target objects in a measuring blind zone of the main receiving lens, and the photoelectric detector is used for receiving the focused first and second echo signals and outputting corresponding electrical signals so as to obtain distance information of the target objects. Ranging of far objects and ranging of close objects can be achieved at the same time by arranging the compensating mirror on the main receiving lens, the detection range is larger, the detection data is more accurate, and the radar measuring blind zone caused by a non-coaxial optical system can be eliminated.

The invention relates to the field of bluetooth communication, particularly to a method and system for distance measurement by bluetooth. Signal strength values of a bluetooth device B are collected through a bluetooth device A, a distance is obtained according to the signal strength values and a model of the distance between the bluetooth device A and the bluetooth device B, and the sum of the obtained distance and the step length is the actual distance, so that the distance measurement between the bluetooth devices is realized. According to the technical scheme, the Bluetooth device A is used for sampling the signal strength values of the bluetooth device B within a preset time, and the greatest signal strength value in the sampled signal strength values is selected as the optimal signal strength value. Because environmental interference is unpredictable, the interference can be stronger within one period, and no interference exists within one period basically, so that the signal fluctuation caused by the environmental interference can be eliminated; by adopting the technical scheme, the fluctuation of the signal values caused by various interference is corrected through the step length, so that the distance measurement is more accurate.

The invention provides an electric vehicle wireless charging device automatic alignment system and method. The system comprises a wireless charging starting button, a wireless charging receiving device, a wireless charging transmitting device, an image recognition automatic locating device and a moving control driving device, wherein the image recognition automatic locating device obtains the distance between the wireless charging transmitting device and the wireless charging receiving device according to collected information, and controls the moving control driving device and the wireless charging receiving device to move in the horizontal direction and the longitudinal direction. According to the electric vehicle wireless charging device automatic alignment system and method, a mobile wireless receiving device is adopted to achieve automatic alignment, compared with a method in which a driver uses a park assist system, the complicated parking procedures are reduced, the installation is simple, and the cost is lowered; the relative distance of a wireless transceiving device is obtained through a binocular vision system, through a horizontal control driving device, a longitudinal control driving device and a vertical lifting control driving device, the purpose that the receiving device moves in the vertical direction is achieved, and the problem that charging efficiency of vehicles is low when underpans differ in height is solved.

The invention discloses a method and a system for indoor wireless positioning and an intelligent terminal. The indoor wireless positioning method includes that positioning bodies and a positioned body are arranged; an intelligent terminal is configured, and an indoor layout, position information of the positioning bodies and labeling information are stored in the intelligent terminal; and a positioning process is achieved. The positioning process includes that the intelligent terminal wakes up the positioned body in a dormant state to achieve wireless communication, the intelligent terminal sends frequency hopping serial information between the intelligent terminal and the positioned body to each positioning body and sets the mode of each positioning body to be an operating mode or a standby mode; the positioning bodies in the operating mode monitor a data package sent to the intelligent terminal from the positioned body, obtain displacement information and send the displacement information to the intelligent terminal; the position of the positioned body is calculated by the intelligent terminal according to the received displacement information and combination with stored position information of the positioning bodies; and the intelligent terminal displays the indoor layout through a display screen, and the position of the positioned body is displayed on the indoor layout.

The invention relates to an intelligent wearable device capable of calculating steps with low power consumption. The intelligent wearable device comprises a processing module and a step calculating system. The step calculating system comprises a sensor and an MCU processor, wherein the MCU processor is used for processing and storing movement data collected by the sensor. The sensor is a gravity sensor and a gyroscope. The MCU processor is provided with a storage part which is used for processing and storing the data acquired by the gravity sensor and the gyroscope. The intelligent wearable device has the advantages that an interrupt signal is transmitted only when the device receives a request signal, the standby embedded system of the processing module is awakened, and step calculation with low power consumption is achieved.

The invention discloses an obstacle recognition method, an obstacle recognition system and a rail car automatic driving device. According to the method, whether an obstacle influencing operation of the rail car exists or not is determined according to image information of a rail area in front of the rail car, and when an obstacle influencing operation of the rail car exists in a front rail area, corresponding braking early warning information is sent out according to the safety braking distance of the rail car and the distance between the rail car and the obstacle. Therefore, distance measurement and early warning of obstacles in front of the operation of the rail car can be realized for driving control. Meanwhile, the automatic driving device for the rail car can acquire image informationof a rail area in front of the rail car in real time; and the obstacle in front of the operation of the rail car is automatically identified, early warned and controlled to drive according to the image information, so that the driving efficiency and the driving safety are effectively improved, the energy consumption is reduced, the operation and maintenance cost is reduced, the working intensityof a driver is greatly reduced, and a technical guarantee is provided for the safe operation of the rail car.

The invention relates to the technical field of radio range finding and particularly to a group range finding method based on a wireless dynamic self-organizing network, wherein the method simultaneously measures distances from one member to multiple other members in the wireless self-organizing network by radio waves. The method ensures range finding precision by roundtrip range finding, and also optimizes a response process. After a member sends a message, other members in the network respond simultaneously after receiving the message. Meanwhile, reception channels of a receiver are increased to ensure the member who initiates the range finding can simultaneously receive range finding messages from other network members. Compared with the prior art, the method has the following beneficial effects that multiple feedbacks can be received at one time such that distances from one member end machine to multiple member end machines can be measured simultaneously, and thus the method is better than a roundtrip time calibration range finding method based on time division. The method may respond immediately, and is obviously better than a range finding method based on network clock synchronization, and the method can perform range finding immediately.

The invention relates to a device and method for rapidly detecting an optical grating auxiliary gap at high precision and relates to the field of photoelectric measurement. The problems that an existing non-contact optical method for detecting the optical grating auxiliary gap is low in measurement precision and efficiency, and a structure is large in size are solved. The device comprises a main grating, a carriage, an indicating grating, three electrical vortex sensors, a grating displacement measuring system and a digital display screen, wherein the three electrical vortex sensors are installed below the indicating grating, the grating displacement measuring system is connected with the output ends of the three electrical vortex sensors, and the digital display screen is connected with the output end of the grating displacement measuring system. The three electrical vortex sensors are distributed in the shape of an isosceles triangle with the largest area, three probes of the sensors are located on the same plane, and the plane is flush with the upper surface of the main grating or spaced by a certain distance which is the initial zero position; the periphery of the indicating grating is plated with chromium metal layers equal in width and thickness, the thickness is larger than 0.65 micrometers, and the width of the chromium metal layers is larger than the diameter of the probes. The measurement precision can reach the micrometer level, measurement is rapidly and accurately performed in real time, the structure is simple and small, and distance measuring for glass is achieved.

The invention generally relates to a multi-spectral binocular vision system, in particular to a coated multi-spectral camera-based stereoscopic vision system and a calibration ranging method thereof.A mosaic coated video multi-spectral detector is used to build the stereoscopic vision system with a multi-spectral binocular ranging function, and a system calibration and matching algorithm for multi-spectral image design. The method specifically comprises the steps of assembly of a hardware system of the multi-spectral detector, multi-spectral image preprocessing, system calibration, feature extraction, semi-global matching optimization, parallax extraction post-processing and the like. The multi-spectral binocular stereoscopic vision imaging system designed by the invention and corresponding ranging algorithm software can be used for ranging of various complex scenes, for example, environmental perception of unmanned vehicles, automatic analysis of video monitoring data, camouflage coating or camouflage cloth target ranging analysis in the military, and the like.

The invention discloses a maneuvering photoelectric detection and identification system for low, slow and small targets, which comprises an optical detection subsystem, a photoelectric parallel processing and identification subsystem and a servo subsystem, and is characterized in that the optical detection subsystem and the photoelectric parallel processing and identification subsystem are erected on the servo subsystem, and the servo subsystem is carried on a mounting platform of a carrier vehicle, the optical detection subsystem is used for collecting multiband optical information from a target and a background; the photoelectric parallel processing identification subsystem comprises a multiband image co-processing module and an information processing master control module, and each band co-processing module is used for carrying out single-frame detection identification on a target according to the image information of the corresponding band; the information processing master control module is used for performing multi-frame detection and identification on a target by adopting a JPEG image compression mode and a track association and multi-frame fusion mode; and the servo subsystem is used for completing target tracking according to the multi-frame detection identification result. The method is high in detection and recognition accuracy, high in maneuverability and capable of performing long-distance detection on a target.

The invention discloses a point target space distance measurement positioning device and method, relates to the technical field of space positioning, and aims to provide the point target space distance measurement positioning device which can conduct both direction locating and distance measurement. The device comprises a driving device, a laser group, a photosensitive timing device and a synchronous device; the laser group can rotate around a preset rotating shaft at an angle speed Omega under the drive of the driving device, the laser group can emit a first laser plane, a second laser plane and a third laser plane, the first laser plane is parallel to the second laser plane, an included angle beta is formed between the third laser plane and the preset rotating shaft, and the synchronous device is located on the third laser plane, passes through an intersection point of the third laser plane and the preset rotating shaft, and is perpendicular to the straight line of the preset rotating shaft, and an included angle alpha is formed between the synchronous device and the first laser plane; the photosensitive timing device is arranged at a to-be-positioned point target, and in the rotation process of the laser group, a photosensitive timing device is capable of recording the time t1, t2 and t3 when scanned by the three laser planes respectively.

The invention discloses an environment sensing method of an unmanned vehicle and a control terminal. The method comprises the following steps: carrying out image fusion processing on the surrounding image data sent by the visual sensors located around the vehicle, the surrounding millimeter wave data sent by the millimeter wave radar sensors located around the vehicle and the surrounding point cloud data sent by the laser radar sensors located at the roof of the vehicle; establishing a three-dimensional surrounding environment model; and obtaining attribute information of all objects on the road according to the surrounding environment model, and generating a driving decision according to the attribute information of all the objects on the road. Through advantage and disadvantage complementation of the laser radar sensor, the visual sensor and the millimeter wave radar sensor, a perfect, stable and reliable environment sensing system is formed.

The invention relates to an HOM interference principle-based range finder. The HOM interference principle-based range finder includes an entanglement source, a delayer, a beam splitter, a first detector, a second detector, a reflector, a semi-transmission and semi-reflection mirror, a reflector to be measured and a coincidence measurement logical calculator; upper photons in the entanglement source are projected onto the beam splitter through the delayer; after being reflected by the semi-transmission and semi-reflection mirror or the reflector to be measured, lower photons in the entanglement source are projected onto the beam splitter; after being split, the upper photons and the lower photons are detected by the first detector and the second detector respectively; and the coincidence measurement logical calculator performs coincidence logical calculation on signals outputted by the detectors. The time delay tau of the delayer is adjusted, so that the lower photons that pass through the semi-transmission and semi-reflection mirror or the reflector to be measured and the upper photons are subjected to interference cancellation, two time delays tau 1 and tau 2 are recorded; and a distance from the reflector to be measured to the semi-transmission and semi-reflection mirror is calculated, wherein the distance is represented by an equation described in the descriptions of the invention. With the HOM interference principle-based range finder of the invention adopted, high-precision distance detection can be achieved. The HOM interference principle-based range finder can be widely applied to fields such as optical coherence tomography, biological tissue structure detection and high precision ranging.

The invention relates to a positioning navigation doorplate which consists of a pluggable double-board doorplate consisting of a big number and a small number, a special navigation identifying device and a borrowed navigation identifying device. Numbers of the doorplates are directly linked up with geographical positions thereof in cities so as to position, direct and measure distance of the doorplates and form a navigation environment similar to GPS; the doorplates have coordinate relation with each other; the numbers of the doorplates in respective isolated traditional cities can be activated to form an integrated doorplate system capable of association and interaction, so that the doorplates become an urban information resource; and the doorplates can provide a platform which is accurate to position and rapid to respond for searching for people, ask for directions, reporting to the police, asking for help, managing public security, leading traffic, managing municipal administration and the like. Therefore, the doorplate has great social and economic benefit.

The invention provides a position-sensorless steel wire rope nondestructive detection equidistant sampling method. The method consists of: processing a magnetic detection sensor signal to obtain a strand wave square wave signal related to a steel wire rope current operating speed and position, and calculating the number of strand wave square wave signal to realize steel wire rope range finding; conducting frequency multiplication on the strand wave square wave signal by a way combining a frequency-locked loop and a phase-locked loop to realize fast tracking of a singular signal; conducting isochronous sampling on the magnetic detection sensor without losing any information on the time axis, and using the strand wave square wave signal to conduct sampling / interpolation on the isochronous sampling data so as to obtain accurate equidistant sampling data; and employing a pre-estimated strand wave square wave signal to conduct sampling / interpolation on the isochronous sampling data, thus avoiding the influence of defects on data acquisition. The method not only realizes steel wire rope range finding, but also realizes position-sensorless equidistant sampling, greatly improves the accuracy of equidistant sampling, and is more beneficial to recognition of steel wire rope nondestructive detection defects.

The invention belongs to the technical field of wireless positioning, and relates to a speed, angle and distance joint estimation method based on conjugate ZC sequence pairs. The method comprises the following steps of: designing a pair of conjugated ZC sequences as sending sequences at a sending end; at a receiving end, receiving multipath signals containing different transmission delays, Doppler frequency offsets and angles, and performing parameter estimation by using a maximum likelihood method; converting a high-dimensional parameter estimation problem into a plurality of low-dimensional parameter estimation problems by using an alternating projection method; for parameter estimation of a single path, based on the property of the ZC sequences, converting two-dimensional estimation of time delay and frequency offset into two one-dimensional estimations, and then carrying out accurate estimation through Newton iteration. According to the method of the invention, high-precision transmission time delay, Doppler frequency offset and angle estimation can be realized under the condition of low bandwidth. Simulation shows that 1cm distance estimation precision, 1m / s speed estimation precision and 0.01-degree angle estimation precision can be realized under the condition of 20MHz bandwidth.

The invention provides a wireless network joint positioning method and system. The method comprises the following steps: acquiring timestamp information according to ranging signals of a plurality of nodes to be positioned; based on the timestamp information, calculating to obtain distance information between any two nodes; and obtaining the positioning information of the plurality of nodes to be positioned according to the distance information between any two nodes. According to the combined positioning method adopted by the invention, the problem that the ranging precision is reduced due to clock errors among the nodes can be effectively eliminated, the signal overhead and the ranging time consumption are greatly reduced, and high-precision network ranging and positioning under a low resource load are realized.

The embodiment of the invention discloses a human face part distance measuring method and device and a vehicle-mounted terminal. The method comprises the following steps: acquiring a face image to besubjected to distance measuring acquired by a camera; according to a plurality of pre-constructed basic face point cloud models and a conversion matrix between the image coordinate system and the camera coordinate system, determining a target weight of each basic face point cloud model capable of fitting to obtain a real face point cloud model, and a target conversion matrix between the head coordinate system and the camera coordinate system; fitting each basic face point cloud model according to each target weight to obtain a real face point cloud model; converting the real face point cloud model into a camera coordinate system according to the target conversion matrix to obtain a target face point cloud model; and according to the target face point cloud model, determining distance information between a specified part in the face image and the camera. By applying the scheme provided by the embodiment of the invention, human face part distance measurement can be carried out on the human face image shot by the monocular camera.

The invention discloses a distance information analysis method based on a single image. The method comprises steps of selecting the single image, determining two target objects needing to be observed,carrying out graying of the image, building a pixel coordinate system in the image after processing, and obtaining pixel coordinates of each point in the image in subsequent demands; selecting a proper reference object from the image, and looking up the data to obtain the basic information of the reference object; positioning a target object in the image by using a cross ratio invariant principle, and restoring the relative position of a photographer by using a method of analyzing the target spatial position. The method is advantaged in that the limitation of partial information height loss in the imaging process is broken through; the method has characteristics of high identification degree, strong operability, no need of knowing related parameters of a shooting camera and the like, andrealizes distance measurement of a target object and the relative position information of the photographer on the target object; the method can well deal with emergencies or urgent need for photo information analysis, can conveniently obtain the distance information between target objects and between the photographer and the target object, and is wide in application range.

The invention discloses a laser welding defocusing amount measuring device. The laser welding defocusing amount measuring device comprises a laser measuring head, a controller box and a computer. A laser transmitter is arranged in the laser measuring head, visible light is transmitted and irradiates to the surface of a welding line, a PSD is arranged in the controller box for receiving welding line reflection light rays, and the laser measuring head and the controller box are fixedly connected. The center line of the laser measuring head intersects with the center line of the controller box, and the computer is electrically connected with the laser transmitter and the PSD. The invention further provides a measuring method using the laser welding defocusing amount measuring device. Compared with the prior art, the technical scheme has the beneficial effects that measuring is convenient and fast, precision is high, and reliability and universality are achieved; and the laser welding defocusing amount measuring reliability, precision and work efficiency can be improved.

The invention discloses a miniature photoelectric passive distance measuring device, which comprises an optical receiving telescope, a row of half transparent and half reflecting mirrors, a first row of imaging sensors, a reflector group, a second row of imaging sensors, and an information processing unit, wherein the first half transparent and half reflecting mirror is located on the optical path of the optical receiving telescope, receives signals of the telescope and transmits and reflects the signals; the second half transparent and half reflecting mirror receives reflection signals of the first half transparent and half reflecting mirror; and each of the rest half transparent and half reflecting mirror receives transmission signals of the former half transparent and half reflecting mirror sequentially, the received signals are transmitted and then reflected, and multiple optical paths are formed; the first imaging sensor receives transmission signals of the first half transparent and half reflecting mirror; each of the rest imaging sensors is located on the reflection optical path of the (odd number)th half transparent and half reflecting mirror; the reflector group receives reflection signals of the (even number)th half transparent and half reflecting mirror; the second row of imaging sensors receives reflection signals of each reflector group; and the information processing unit receives video signals of multiple optical paths of the first row of imaging sensors and the second row of imaging sensors, and distance inversion algorithm processing is carried out on the received video signals.

The invention relates to a multifunctional double-frequency-modulation coherent laser radar, which comprises: a single-frequency laser, a beam splitter, a first optical frequency modulator, a laser amplifier, a transmitting-receiving telescope, an optical scanner, a second optical frequency modulator, an optical pluralizing device, a signal generator, a digital delay controller and a signal acquisition and processor. The multifunctional double-frequency-modulation coherent laser radar can realize laser ranging, speed measurement, three-dimensional scanning imaging, laser synthetic aperture imaging and other functions, has the characteristics of simple system structure, easy integration and miniaturization, can realize high-precision data acquisition of a target, inhibits background light interference, effectively improves the imaging sensitivity, and is particularly suitable for multi-dimensional information detection of a long-distance target.

The invention discloses a distance measurement system and a distance measurement method applied to canopy reflectance spectra measurement; the distance measurement system comprises two distance measurement sensors, an embedded processor and a mounting bracket, the embedded processor is placed in the middle of the mounting bracket, the two distance measurement sensors are respectively arranged on both ends of the mounting bracket, the two distance measurement sensors are used for image information acquisition of crop canopy and are connected with a signal input end of the embedded processor, the embedded processor outputs height information between the distance measurement system and the canopy to a canopy reflectance spectra measurement device connected with the embedded processor, the canopy reflectance spectra measurement device is placed in the middle of the mounting bracket, and a distance measurement system sensor detection terminal facing the canopy and a canopy reflectance spectra measurement device detection terminal facing the canopy are in the same plane. The canopy distance measurement system is constructed by adopting a binocular vision technology and the embedded processor, the processing of binocular vision data can be realized by use of an embedded system, and the measurement of the canopy distance can be realized by using binocular vision depth information.

The invention discloses a multifunctional geological compass for mineral equipment, relating to the technical field of automation. A cover plate is mounted on the side wall of a shell through a hinge,and a light reflection mirror is embedded into the cover plate; a mounting slot is formed in the shell, a magnetic needle is mounted in the mounting slot through a hinging shift, and a dial is mounted on the edge of the bottom in the mounting slot; a magnifying lens is mounted on the inner edge of the outer side wall of the mounting slot, and a gradienter is mounted at the bottom in the mountingslot; a collimation target board is mounted on the right side wall of the shell, and lineation sawteeth are arranged at two ends of the right side wall of the collimation target board; a handheld handle is mounted at the bottom of the shell, a grounding needle is connected to the bottom of the handheld handle through threads; and two-dimensional ranging laser heads are mounted at the upper end andright side of the shell, a plugging slot is formed in the upper end in the shell, and positioning columns are arranged on two side walls of the plugging slot. The multifunctional geological compass has ranging and measurement functions and is simple and convenient to operate; and rapid handholding can be realized, and the geological compass has multiple functions.

The invention discloses a novel multifunctional three-dimensional scanner which comprises a scanner main body, wherein a camera I is arranged at the position, which is close to the front end, of the outer surface of the top end inside the scanner main body; and a connecting shaft is fixedly connected to the outer surface of the rear end of the camera I. The novel multifunctional three-dimensionalscanner disclosed by the invention is provided with a connecting ring, a power generation motor and a honeycomb plate, so that the damaged camera and laser transmitter can be detached and replaced intime, and the condition that normal use of the three-dimensional scanner is influenced because the scanner cannot be repaired in time is avoided. Meanwhile, the three-dimensional scanner can be detached to be singly used according to needs and is more convenient, the condition that time is wasted because a specified site needs to be found for charging is avoided by virtue of manual power generation, and timely use of the three-dimensional scanner is avoided from being influenced. In addition, the weight can be well lightened while ensuring the original shell hardness, the scanner is convenientto move and use, the phenomenon that the using effect is influenced due to heavy equipment is avoided, and the scanner brings excellent application prospects.

The invention relates to the field of bluetooth communication, particularly to a method and system for distance measurement by bluetooth. Signal strength values of a bluetooth device B are collected through a bluetooth device A, a distance is obtained according to the signal strength values and a model of the distance between the bluetooth device A and the bluetooth device B, and the sum of the obtained distance and the step length is the actual distance, so that the distance measurement between the bluetooth devices is realized. According to the technical scheme, the Bluetooth device A is used for sampling the signal strength values of the bluetooth device B within a preset time, and the greatest signal strength value in the sampled signal strength values is selected as the optimal signal strength value. Because environmental interference is unpredictable, the interference can be stronger within one period, and no interference exists within one period basically, so that the signal fluctuation caused by the environmental interference can be eliminated; by adopting the technical scheme, the fluctuation of the signal values caused by various interference is corrected through the step length, so that the distance measurement is more accurate.

The invention discloses an automatic range-measuring control device of a radiator. The automatic range-measuring control device of a radiator includes a radiator body on a housing and radiating holesin the housing, and also includes a temperature sensing module, an infrared range-measuring circuit, a pre-amplification circuit, a control circuit and a display circuit, wherein the temperature sensing module is used for obtaining the current temperature of the housing; the infrared range-measuring circuit is used for detecting a human body in the area where the housing is to obtain an analog signal, and then the analog signal is amplified by the pre-amplification circuit and then is input into the control circuit; the control circuit is used for obtaining the range value according to the received amplified human body analog signal, and controlling the display circuit to display the current temperature of the housing according to the range value; and the pre-amplification circuit includesfirst to fourth capacitors, first to fourth resistors, a first amplifier and a second amplifier. The automatic range-measuring control device of a radiator utilizes the simple circuit structure to realize two-stage amplification effect, can effectively suppress the noise in the circuit, can intelligently realize range-measuring and prompting, and can improve the safety.

The invention discloses road intelligent analysis equipment for a new energy automobile, which comprises a sensing module, an A / D switch, an analysis module and a display module, and is characterized in that the analysis module is used for analyzing, identifying, judging and processing digital information, so that identification and distance measurement of static objects, identification and distance measurement of dynamic objects and judgment of movement speed and direction are realized; according to the technical scheme, the road condition of the road surface is sensed through the sensing module, static objects and dynamic objects on the road surface are captured, digital information transmitted by the analysis module is analyzed, recognized, judged and processed, and therefore recognition and distance measurement of the static objects are achieved; the road intelligent analysis equipment has the advantages that the dynamic object is identified, the distance is measured, the movement speed and direction are judged, the flatness of the road surface is measured, the signal lamp and the warning board are identified, the identification accuracy is high, the movement track of the dynamic object can be simulated, and the accuracy of the road intelligent analysis equipment is greatly improved.

The invention discloses a patch type wireless radio frequency identification technology distance measurement system. The system comprises a wireless radio frequency system and a positioning and ranging system, the wireless radio frequency system comprises a wireless control unit, a central processing unit, a communication distance unit, an information feedback unit, a distance analysis unit, a radio wave transmitting unit, a data reading unit, an RFID chip and a data storage unit, and the invention relates to the technical field of wireless radio frequency identification. According to the patch type wireless radio frequency identification technology ranging system, through the communication distance unit, the information feedback unit, the distance analysis unit, the radio wave emission unit, the data reading unit, the RFID chip and the data storage unit, by utilizing a radio wave non-contact rapid information exchange and storage technology and through non-contact two-way communication, the influence of the change of obstacles or objects in the space on a radio frequency identification ranging or positioning result can be effectively reduced, and the ranging and positioning precision is greatly improved under the condition of not increasing the system complexity.

The invention discloses a multi-terminal line protection fault positioning and distance measuring method, which comprises the following steps of: after a pilot current differential protection action configured by a multi-terminal line protection device, calculating each sequence voltage and sequence current of a line node according to the voltage and current at a protection installation position; calculating each sequence voltage at a T node according to each sequence voltage and sequence current of a line node, wherein each T node is connected with three electric quantity nodes, so that three positive sequence voltages, three negative sequence voltages and three zero sequence voltages can be obtained; according to different fault types, setting the sequence component voltage of the maximum voltage difference as discrimination voltage; and according to sequence voltage differences derived from different sides of the T node, determining the position of a fault point is judged in combination with a dichotomy; and when the fault point is at the T node, directly acquiring the distance measurement result; or when the fault point is on the line, equivalizing the electric quantity nodes on the two sides of the fault point to a double-end system for distance measurement. According to the method, accurate distance measurement can be realized when a fault occurs in a multi-terminal line with three terminals and more than three terminals.