A method for determining geo-position of a target by an aircraft includes: receiving navigation data related to the aircraft including aircraft attitude information; receiving multilateration information related to the target including an angle to the target; calculating an axis for a cone fixed to the aircraft, based on the received aircraft attitude information; calculating a central angle for the cone from the received angle to the target; generating two vectors orthogonal to the cone axis; calculating a cone model from the axis, the central angle and the two vectors; and intersecting the cone model with an earth model to obtain a LEP curve, wherein the LEP curve is used to determine the geo position of the target.

A method of locating a coal-rock main fracture by an electromagnetic radiation from a precursor of a coal-rock dynamic disaster is provided. At least four groups of three-component electromagnetic sensors are arranged in the underground tunnels, and each group of sensors includes three directive antennas for receiving electromagnetic signals orthogonal to each other. The electromagnetic signals are collected by a monitoring host. The signals are ensured to be received by different sensors synchronously via an atomic clock. The direction of the magnetic field line is determined by performing a vector superposition on strengths of the three-component electromagnetic signals of each group of sensors. The planes of electromagnetic wave propagation perpendicular to the direction of the magnetic field line are determined accordingly. The location of the coal-rock fracture is determined by the intersection point of the planes of electromagnetic wave propagation determined by the multiple groups of sensors.

A method of locating a coal-rock main fracture by an electromagnetic radiation from a precursor of a coal-rock dynamic disaster is provided. At least four groups of three-component electromagnetic sensors are arranged in the underground tunnels, and each group of sensors includes three directive antennas for receiving electromagnetic signals orthogonal to each other. The electromagnetic signals are collected by a monitoring host. The signals are ensured to be received by different sensors synchronously via an atomic clock. The direction of the magnetic field line is determined by performing a vector superposition on strengths of the three-component electromagnetic signals of each group of sensors. The planes of electromagnetic wave propagation perpendicular to the direction of the magnetic field line are determined accordingly. The location of the coal-rock fracture is determined by the intersection point of the planes of electromagnetic wave propagation determined by the multiple groups of sensors.

An antenna device configured for wireless positioning. The antenna device includes a ground plane having a polygonal shape comprising at least 4 side edges. A plurality of chip antenna elements tuned to a predetermined radio frequency are each singly provided at one of said side edges with a spacing between adjacent ones of said chip antenna elements corresponding to ½ of a wavelength of said predetermined radio frequency. A patch antenna element tuned to said predetermined radio frequency is provided at a center portion of a front side of the ground plane.

An antenna device configured for wireless positioning. The antenna device includes a ground plane having a polygonal shape comprising at least 4 side edges. A plurality of chip antenna elements tuned to a predetermined radio frequency are each singly provided at one of said side edges with a spacing between adjacent ones of said chip antenna elements corresponding to ½ of a wavelength of said predetermined radio frequency. A patch antenna element tuned to said predetermined radio frequency is provided at a center portion of a front side of the ground plane.

A device and method for improving the accuracy of angle of arrival and departure computations is disclosed. The device and method rely on manipulation of the antenna switching pattern to achieve an improved calculation of arrival angle. In one embodiment, the device calculates an estimate angle of arrival using conventional methods. The device then determines which of a plurality of different antenna switching pattern yields the more accurate results at this estimated angle of arrival. The AoA measurement is then repeated using the preferred antenna switching pattern. In another embodiment, the device captures the amplitude and/or phase of the signal from each antenna element. The device then sorts these antenna elements and defines a preferred antenna switching pattern based on the sort list. The AoA measurement is then performed using the preferred antenna switching pattern. In another embodiment, neural networks may be utilized to determine the preferred antenna switching pattern.

A device and method for improving the accuracy of angle of arrival and departure computations is disclosed. The device and method rely on manipulation of the antenna switching pattern to achieve an improved calculation of arrival angle. In one embodiment, the device calculates an estimate angle of arrival using conventional methods. The device then determines which of a plurality of different antenna switching pattern yields the more accurate results at this estimated angle of arrival. The AoA measurement is then repeated using the preferred antenna switching pattern. In another embodiment, the device captures the amplitude and/or phase of the signal from each antenna element. The device then sorts these antenna elements and defines a preferred antenna switching pattern based on the sort list. The AoA measurement is then performed using the preferred antenna switching pattern. In another embodiment, neural networks may be utilized to determine the preferred antenna switching pattern.

A device and method for improving the accuracy of angle of arrival and departure computations is disclosed. The device and method rely on manipulation of the antenna switching pattern to achieve an improved calculation of arrival angle. In one embodiment, the device calculates an estimate angle of arrival using conventional methods. The device then determines which of a plurality of different antenna switching pattern yields the more accurate results at this estimated angle of arrival. The AoA measurement is then repeated using the preferred antenna switching pattern. In another embodiment, the device captures the amplitude and/or phase of the signal from each antenna element. The device then sorts these antenna elements and defines a preferred antenna switching pattern based on the sort list. The AoA measurement is then performed using the preferred antenna switching pattern. In another embodiment, neural networks may be utilized to determine the preferred antenna switching pattern.

This specification relates to estimation of a location of a mobile device using one or more locator devices. This specification describes an apparatus comprising: means for receiving, from one or more locator devices, each locator device comprising an antenna array, information indicative of a bearing from the antenna array of each of the one or more locator devices to a mobile device; means for determining parameters of a Kent distribution for each of the one or more locator devices based on the received information and predetermined characteristics of the antenna array; and means for determining an estimated position of the mobile device by performing an optimisation process on an objective function that is dependent on the Kent distribution parameters for each of the one or more locator devices.

This specification relates to estimation of a location of a mobile device using one or more locator devices. This specification describes an apparatus comprising: means for receiving, from one or more locator devices, each locator device comprising an antenna array, information indicative of a bearing from the antenna array of each of the one or more locator devices to a mobile device; means for determining parameters of a Kent distribution for each of the one or more locator devices based on the received information and predetermined characteristics of the antenna array; and means for determining an estimated position of the mobile device by performing an optimisation process on an objective function that is dependent on the Kent distribution parameters for each of the one or more locator devices.