8results about "Direction finders using radio waves" patented technology

The present application relates to the technical field of image processing, in particular to a kind of real-time optical tracking method and system of moving target based on passive guidance.The approximate coordinates of moving target are obtained by passive direction finding station;And according to the approximate coordinates, control laser illumination unit to light moving target body, utilize binocular camera unit to carry out image acquisition and visual analysis to moving target, to obtain the position change of moving target;Combining the position change of moving target, determine the trajectory pose of moving target.Using call camera unit, the whole tracking of moving target is carried out, and the flight state of moving target collected is transmitted to host computer in real time for display.The present application realizes real-time positioning of moving target by the fusion mode of passive direction finding station and binocular optical system, realizes real-time accurate positioning of moving target in the case of building, vegetation dense and low visibility.

A calibration method of calibrating a direction finding, DF, device (12) is described. The calibration method comprises the following steps: - placing a mobile test device (14) at a first position relative to the DF device (12) to be calibrated, wherein the mobile test device (14) comprises a GNSS module (24) and a transmission module (26); - obtaining, by an analysis module (22), a GNSS position of the mobile test device (14); - generating and transmitting, by the transmission module (26), a wireless test signal; - receiving, by the DF device (12) to be calibrated, the wireless test signal; - determining, by the DF device (12), a DF azimuth angle based on the wireless test signal; and - determining, by the analysis module (22), an error angle based on the DF azimuth angle and based on the obtained GNSS position. Furthermore, a calibration system (10) is described.

System and method for selecting location data to be used as the location of a user device using a location-based service. Horizontal location data and vertical location data for the user device are obtained from multiple sources. A horizontal location uncertainty and a vertical location uncertainty are determined or obtained for each source. In response to determining that both the horizontal location uncertainty meets a threshold horizontal uncertainty value and the vertical location uncertainty meets a threshold vertical uncertainty value, the corresponding source is identified as compliant. In response to identifying no compliant sources, a lowest horizontal location uncertainty and a lowest vertical location uncertainty are selected from among the plurality of sources.

This invention discloses a generative deception interference detection and suppression method based on coprime arrays. After signal despreading, a grid-adaptive orthogonal matched pursuit algorithm is used for DOA estimation, and the sum of squared errors (SSE) of the DOA estimation results is used as the detection metric for deception interference. This is combined with a linearly constrained minimum variance algorithm to suppress generative deception interference. This invention maintains a high deception interference detection rate even in complex scenarios with severe multipath interference. It can detect and suppress generative deception interference before the induced correlation peak is stripped, adjust the array's main beam to align with the navigation signal, and improve the navigation signal's resistance to generative deception interference.

An electronic device comprises a first wireless communication circuit, an orientation sensor, and a controller. The first wireless communication circuit is configured to transmit and receive first wireless signals via a plurality of antennas. The orientation sensor is configured to provide heading information indicative of an orientation of the electronic device in a reference frame. The controller is configured to obtain the heading information from the orientation sensor, and to control the first wireless communication circuit to transmit at least one first wireless signal comprising information indicative of the heading information and an identifier of the electronic device. The controller is configured to receive, via the first wireless communication circuit, at least one first wireless signal transmitted by another device, and to determine, based on differences in arrival time and / or phase of the at least one first wireless signal at the plurality of antennas, a direction vector from the electronic device towards the other device. The controller is configured to determine, based on a time-of-flight associated with the at least one first wireless signal, a distance between the electronic device and the other device, and to compare the direction vector with the heading information and, when the direction vector satisfies a directional criterion relative to the heading information and the distance is within a predetermined range, generate a target-determination signal or proximity signal.

The application provides a vehicle occupant position detection method and device, a vehicle and a medium. The method comprises: detecting the distance and angle of a target occupant in a vehicle by using a UWB multi-array antenna to obtain ranging and angle measurement information; calling a preset model algorithm to calculate the position of P relative distances and Q angles of arrival in the ranging and angle measurement information to obtain an estimated position of the target occupant; and outputting the estimated position as the seating position of the target occupant in the vehicle when the estimated position meets the position requirements corresponding to the preset model algorithm. In this way, the technical problems of low accuracy of occupant position detection and potential safety hazards in the prior art can be solved.

Systems and methods for a label query system are disclosed herein. An exemplary system includes: a label associated with a good; an anchor configured to query the label at an initial transmission rate and to determine an angle of arrival (AOA) based on signal data received from the label; and a server communicatively coupled to the anchor. The server can be configured to: receive initial information corresponding to the label, the initial information indicating one or more initial instances in which the anchor queries the label at a second transmission rate different from the initial transmission rate.The server can further be configured to receive a label listing from the anchor containing the label, to determine a first instance occurrence for the label based on the first information, and to send a request to the anchor causing the anchor to query the label at the second transmission rate.