Patents
Literature
Patsnap Copilot is an intelligent assistant for R&D personnel, combined with Patent DNA, to facilitate innovative research.
Patsnap Copilot

117results about How to "Reduce the impact of positioning accuracy" patented technology

Fingerprint database construction method of WiFi indoor positioning system

The invention discloses a fingerprint database construction method of a WiFi indoor positioning system. The method comprises the following steps: determining the position and the coordinates of a reference point, capturing the media access control address of access points at the reference point, collecting signal strength of all the access points in a media access control address list, and sending a sampling file to a server; conducting statistical treatment on signal strength data in the sampling file to obtain a fitting probability distribution curve, conducting correlation correction on the fitting probability distribution curve, conducting truncation processing on the probability distribution curve obtained after the correlation correction, calculating the probability of each decibel milliwatt value, conducting normalization processing, and finally generating a fingerprint database. The method solves the problems that the establishment process of a traditional fingerprint database is longer in consumed time, the processing is tedious, the fingerprint information is insufficient, and updating and maintenance are not facilitated. Due to the parallelization of fingerprint collection, the establishment of the fingerprint database is accelerated, optimized processing is carried out on the collected fingerprint data, and the fingerprint database is more accurate and comprehensive.
Owner:SHANGHAI JIAO TONG UNIV

Indoor positioning method based on multi-layer fingerprint matching

The invention discloses an indoor positioning method based on multi-layer fingerprint matching. The indoor positioning method based on multi-layer fingerprint matching includes a first step of building four layers of fingerprint maps according to indoor environment; a second step of matching a signal intensity vector actually received by a user in a rule fingerprint map and a random fingerprint map to obtain positioning results of the two times of matching by using a k-nearest neighbor method; a third step of transforming the signal intensity vector actually received by the user into a distance vector, and matching the distance vector in a rule fingerprint distance map and the random fingerprint distance map to obtain positioning results of the two times of matching by using the k-nearest neighbor method; a fourth step of averaging user estimated position coordinates obtained according to the four-layer fingerprint matching to obtain final user estimated position coordinates. The indoor positioning method based on multi-layer fingerprint matching provided by the invention builds a fingerprint database according to received signal intensity and actual positions of rule reference points and random reference points and distances based on a path-loss model, thereby reducing effects of indoor multipath environment by using a multi-layer fingerprint strategy and improving indoor positioning accuracy.
Owner:BEIHANG UNIV

Enhanced position fingerprint indoor positioning method integrating Wi-Fi and Bluetooth

The invention discloses an enhanced position fingerprint indoor positioning method integrating Wi-Fi and Bluetooth. The method is integrated with Wi-Fi and Bluetooth enhanced position fingerprint indoor positioning. The two modes of Wi-Fi and Bluetooth adopt signal strength indication RSSI position fingerprints to carry out indoor positioning, only the mapping relation between the received signalstrength and the spatial physical position is needed for positioning, the cost of a positioning system can be effectively reduced, and the robustness of the multipath effect in the complex environmentis greatly improved. RSSI parameters are dynamically corrected according to RSSI vector values, received from a plurality of preset access point AP node devices in a to-be-tested environment, of respective corresponding test positions, and a result obtained by a position fingerprint method can be close to an actual position to the greatest extent by using a k-weighted neighbor method, so that thepositioning precision is improved. The present invention uses advantages of dual-mode positioning are brought into full play through decision-level fusion of the Wi-Fi and the Bluetooth, and the indoor positioning precision can be effectively improved under the condition of self-adapting to most complex environments.
Owner:NANJING UNIV OF POSTS & TELECOMM

Precise and synchronous positioning and time-keeping method and system of Mars orbiting detector

The invention discloses a precise and synchronous positioning and time-keeping method and system of a Mars orbiting detector. The precise and synchronous positioning and time-keeping method comprises the following steps: firstly inputting initial data including a simulated nominal orbit and relative parameters for filtering initialization; simulating observation data, and simulating the observed quantity of a pulsar according to a measurement equation of the pulsar, wherein measurement noises relative to the observed quantity comprise clock errors, and the clock errors are simulated by a clock error model; and performing adaptive Kalman filtering according to a filtering state equation and an observation equation of self-positioning and time keeping of the Mars orbiting detector to obtain orbits and the clock errors of the detector. According to the precise and synchronous positioning and time-keeping method and system disclosed by the invention, on the basis of establishing an observation model of an X-ray pulsar, the observation model, a detector kinetic model and the clock error model of a satellite-borne atomic clock are organically combined, and the position, speed and clock error parameters of the detector are also estimated so as to ensure that the clock error correction can be achieved, influences of the clock errors to the positioning accuracy can also be weakened, and the self-positioning accuracy can also be improved.
Owner:WUHAN UNIV

High-precision positioning method based on multi-QR-code vision

The invention relates to the technical field of indoor positioning, in particular to a high-precision positioning method based on multi-QR-code vision. The high-precision positioning method includes the steps that a plurality of QR codes are arranged on a plane, and a camera is used for shooting by being perpendicular to the plane; the number of the QR codes in a shot image is greater than 1; a pixel coordinate system is established by taking the shot image as the edge, the pixel coordinates of vertexes of the QR codes are extracted, and the pixel distance of the center points of every two QRcodes is calculated; according to the pixel coordinates of the length-width image center points of the shot image, the pixel distance from the center point of any QR code to the center point of the image is calculated; according to the geographic coordinates of the center points of the QR codes, the actual distance of any two QR codes is obtained, and the ratio of the pixel distance in the currentshot image to the actual distance is obtained; then the actual distance D1 from the center points of the QR codes to the center point of the image is obtained; and in a geographic coordinate system,a circle is drawn with the center point of each QR code as the circle center and the actual distance D1 as the radius, and the geographic coordinates of the center point of the image are obtained. According to the method, the size and shape of the QR codes are not limited, and accurate positioning can be realized.
Owner:成都四相致新科技有限公司

Indoor mobile robot oriented IMU/WSN (inertial measurement unit/wireless sensor network) integrated navigation method

The invention discloses an indoor mobile robot oriented IMU/WSN (inertial measurement unit/wireless sensor network) integrated navigation method. The method includes: creating a relative coordinate system; acquiring optimal estimation of distance square and distance square change rate between unknown nodes and reference nodes of a wireless communication channel at current moment; acquiring optimal estimation of the distance square and the distance square change rate, between the unknown nodes and the reference nodes, obtained by IMU resolving at current moment; constructing a main filter; finally acquiring optimal estimation of the location, speed and attitude of the unknown nodes at the current moment. The method has the advantages that local filters are adopted in both the WSN and the low-cost IMU, accuracy of data collected by sensors is improved effectively, and precision improvement in the subsequent data fusion process of the main filter is benefited; the main filter describes running status of a system more accurately than the location, speed and acceleration error of the traditional mobile robot localization field, and precision of data fusion is improved beneficially.
Owner:UNIV OF JINAN

RSSI wireless sensor network three-dimensional cooperative positioning method

The invention relates to an RSSI wireless sensor network three-dimensional cooperative positioning method, which comprises the following steps of: (1) acquiring received signal strength RSSI of an unknown node to be positioned, performing data preprocessing and feature extraction, and performing predicting to obtain a coarse positioning result; (2) setting an RSSI threshold value, selecting a nodewith higher positioning precision from unknown nodes, and judging the selected node by using a sub set to obtain a secondary selection cooperative node; and finally, screening out nodes meeting the precision requirement as optimal cooperative nodes by utilizing an anchor node replacement principle. (3) drawing a circle by taking the distance between every two nodes selected according to a precision optimization strategy as a radius, wherein the quadrilateral area is composed of inner side coordinates of intersection points of two adjacent circles, the coordinates of the quadrilateral area areobtained according to the principle of a rotation matrix, and finally the mass center of the quadrilateral area is calculated and serves as the coordinates of unknown nodes to serve as a final corrected positioning result. The indoor positioning precision can be improved.
Owner:广东华东爆破拆迁工程有限公司

UWB/INS combined indoor positioning method based on particle filter algorithm

The invention relates to a UWB / INS combined indoor positioning method based on a particle filter algorithm. The UWB / INS combined indoor positioning method based on the particle filtering algorithm isprovided aiming at the situation that the UWB (ultra wide band) ranging result is easily interfered by a complex environment in a non-line-of-sight environment and positioning precision is influenced.A distance between a person to be positioned and each reference base station is obtained through a UWB system, and the east direction position and the north direction position of the person are calculated through a UWB position calculation unit. The three-axis acceleration, the three-axis angular velocity and the three-axis magnetic field intensity of the person in the walking process are obtained through an INS (inertial navigation system), and the step length, the east-direction step speed, the north-direction step speed, the stepping time and the attitude angle of the person in the walkingprocess are calculated through an INS resolving unit; data fusion on the UWB system calculation result and the INS system calculation result is carried out through a particle filtering algorithm; andlastly, purposes of reducing influence of a non-line-of-sight complex environment and improving positioning precision are achieved.
Owner:UNIV OF ELECTRONICS SCI & TECH OF CHINA

Time domain signal waveform measuring method and device and digital oscilloscope

The invention relates to a time domain signal waveform measuring method, a measuring device and a digital oscilloscope. The waveform measuring method comprises the following steps of: acquiring waveform information of a digital time domain signal; forming a waveform search area of a target amplitude according to the waveform information; calculating to obtain an expected value of each point set inthe waveform search area, and determining a virtual sampling point of the target amplitude in the waveform search area according to the expected value; and outputting amplitude information and time information of the virtual sampling point. The waveform measuring method for the protection can reduce the influence of sampling channel noise, ADC quantization errors and insufficient sampling on thepositioning accuracy of the focus, improve the approximation degree of the focus to the real waveform, and particularly reduce the influence of ADC quantization errors and insufficient sampling rate when the virtual sampling point corresponding to the attention point do not coincide with the real sampling point. The positioning accuracy of the focus is improved to be approximate to an ideal state,and the errors of operations such as optimal sampling point positioning, time (such as period) measurement and the like can be reduced to the maximum extent.
Owner:SHENZHEN CITY SIGLENT TECH

Mobile equipment positioning method, mobile equipment positioning device and electronic equipment

The invention discloses a mobile equipment positioning method and a mobile equipment positioning device. The mobile equipment positioning method comprises the following steps: determining a first group of pose parameters when the mobile equipment shoots a current frame image, and determining a top view of the current frame image; determining a plurality of second groups of pose parameters based onthe first groups of pose parameters; in the high-precision map, determining a plane area in a preset range of a geographic position when the current frame image is shot; projecting the top view intothe plane area based on the plurality of second groups of pose parameters to obtain a plurality of second projection drawings; and based on the matching degree between the plurality of second projection images and the image content of the plane area in the high-precision map, determining a pose parameter of the mobile device when the mobile device shoots the current frame image from the pluralityof second group pose parameters. According to the embodiment of the invention, the method can greatly reduce the impact on the positioning precision from an environment condition, improves the positioning precision, and greatly reduces the positioning cost through the visual camera.
Owner:BEIJING HORIZON ROBOTICS TECH RES & DEV CO LTD

Method for positioning forest fire by forest fire fighting helicopter

The invention belongs to the technical field of avionics, and relates to a method for positioning a forest fire by a forest fire fighting helicopter. Onboard infrared detection equipment is used for detecting the forest fire in a forest; when detecting the forest fire, the infrared detection equipment informs an onboard computer, and outputs a pitching angle and an orientation angle of the infrared detection equipment at the moment; an aviation state sensor, an atmosphere sensor, a global positioning system (GPS) sensor and the like are used for acquiring flying parameters, such as the posture, the height, the position and the like of the helicopter; and the position of the forest fire is calculated according to the pitching angle and the orientation angle of the infrared detection equipment and the flying parameters. According to the method, the influence of a flying posture and a complicated terrain on the positioning precision is reduced greatly, so that a pilot can accurately position the forest fire at a position far away from the forest fire without driving the helicopter above the forest fire or close to the forest fire, and the safety is improved. According to the method, the position of the forest fire can be accurately and stably positioned, and firefighters can be correctly guided to put out the fire, so that relatively high loss can be avoided.
Owner:SHAANXI QIANSHAN AVIONICS

Lane level positioning method, device, system and related equipment

The invention discloses a lane level positioning method, device and system and related equipment. The method comprises the steps of positioning the current position of a vehicle, randomly generating a preset number of position points around the current position; for each position point, determining the probability that the position point is possibly a real vehicle position, when the probability is determined, determining the probability that each position point may be the real position of the vehicle in each mode based on various modes such as electronic map errors, line types of lane lines on two sides of a lane where the vehicle is located sensed by at least two sensing technologies, distances to the lane lines on the two sides and the like, fusing the probabilities obtained by the various modes to obtain the final probability, and positioning the position of the vehicle based on the final probability. According to the method, the problem of low accuracy when a single mode is adopted for positioning is solved, the positioning precision of vehicle positioning and robustness in different scenes are improved, lane-level accurate positioning is realized, the method can adapt to different-level positioning requirements of different scenes, and the influence of external factors on the positioning accuracy is reduced.
Owner:ALIBABA GRP HLDG LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products