Certain cellular communication systems may use beamforming to create distinct signal beams in different radial directions relative to a base station. Upon receiving a request for the location of a mobile device, a position calculation function is used to calculate the location of the mobile device based on multiple types of location-related data. The location-related data may indicate the direction of the directional signal beam that is currently being used for communications between the mobile device and a base station. The direction may be used in conjunction with other location-related data, such as distance information, to estimate the location of the mobile device.

The invention relates to a method for determining by a direction finder (DF) the direction to a Target, which comprises (a) providing an antenna at the DF, and an array of antennas at the Target; (b) providing a compass at each of the DF and the Target, for determining the azimuth of the DF Heading and of the Target Heading, respectively, with respect to the North; (c) providing at the DF a look-up table which describes n antenna patterns, one per Transmission Mode that may be used respectively at the Target; (d) sequentially performing x Transmission Modes from the Target, each time using another pair of antennas, and during each of the Transmission Modes intentionally, and in a controlled manner attenuating a reception signal at the DF until a loss of communication, and recording the respective attenuation levels; (e) based on the x recorded attenuations levels and the look up table, determining by the DF the direction from the Target to the DF; and (f) receiving at the DF the azimuth of the Target, and based on (i) the determined direction from the Target to the DF (ii) azimuth of the Target; and (iii) azimuth of the DF; calculating by the DF the direction from the DF to the Target.

The present disclosure discloses a three-dimensional co-prime cubic array direction-of-arrival estimation method based on a cross-correlation tensor, mainly solving the problems of multi-dimensional signal structured information loss and Nyquist mismatch in existing methods and comprising the following implementing steps: constructing a three-dimensional co-prime cubic array; carrying out tensor modeling on a receiving signal of the three-dimensional co-prime cubic array; calculating six-dimensional second-order cross-correlation tensor statistics; deducing a three-dimensional virtual uniform cubic array equivalent signal tensor based on cross-correlation tensor dimension merging transformation; constructing a four-dimensional virtual domain signal tensor based on mirror image augmentation of the three-dimensional virtual uniform cubic array; constructing a signal and noise subspace in a Kronecker product form through virtual domain signal tensor decomposition; and acquiring a direction-of-arrival estimation result based on three-dimensional spatial spectrum search.

Provided is a terminal apparatus including: a receiver configured to detect a transmission direction of a signal used for communication with at least one base station apparatus; and a transmitter configured to transmit, to a location server, base station direction information for indicating the transmission direction detected.

A process of screening direction finding solutions to reduce the number of valid direction finding solution rejections while maintaining an acceptable level of wild bearings being reported utilizing the proximity of the correlation values of the highest correlation and second highest correlation given a correlation pattern of a detected signal of unknown origin.

A method performed by a first communication device operating in a wireless communications network. The first communication device obtains a set of correspondences associating: i) each set (.sub.i) of a plurality of sets of antenna weights (.sub.1 . . . .sub.i) having been sent by a third communication device in response to having received a respective set (RSs.sub.i) of a plurality of sets of radio signals (RSs.sub.1 . . . RSs.sub.i) from a set of antenna ports in a second communication device, with ii) a respective direction of transmission (d.sub.i) between the second communication device and the third communication device. The respective direction is relative to an orientation (.sub.i) of the second communication device. The respective direction of transmission (d.sub.i) is a selected direction of transmission (d.sub.i,i). The first communication device then initiates transmission of a new radio signal, based on the obtained set of correspondences.

A device for detecting and/or tracking a projectile has a receiving antenna, for receiving at least an electromagnetic signal emitted by at least one radar, at least one amplifier configured to amplify the electromagnetic signal received by the receiving antenna, and at least one emitting antenna. The emitting antenna is configured to return, at an output of the device, an amplified electromagnetic signal for calculating data indicative of the trajectory of the projectile based at least on the amplified electromagnetic signal. A system for detecting a projectile has a transmitting device mounted on the projectile, a radar configured to sense an electromagnetic signal produced and sent by the transmitting device. The signals emitted from the projectile are limited to the electromagnetic signal sent by the transmitting device, and a processing unit, configured to calculate data indicative of the trajectory of the projectile, based on the sensing of the electromagnetic signal.

Devices and methods of estimating the AoD of a STA are generally described. The STA receives comparison symbols from a first AP antenna. The comparison symbols are received prior to and after switching of transmitter chains from a first set of antennas to a second set of antennas. AoD symbols are received immediately after the comparison symbols. A phase and amplitude correction is determined based on a phase and amplitude change between the comparison symbols and the second AoD symbol corrected based thereon. The AoD is subsequently estimated based on the symbol measurements.

A method and apparatus for receiving signals from an unknown transmitting source and providing the location of the unknown transmitting source comprising a series of channels for receiving signals radiated by the unknown transmitting sources, generating preprocessed time domain data and generating a SAR image depicting a location of the unknown transmitting source, and a processor for processing the preprocessed time domain data to enhance a pixel value at each pixel location within the SAR image by summing signal data from each channel related to each pixel location to generate an enhanced SAR image.

In some examples a method includes receiving, with an Access Point (AP), a request from a wireless device to access a network through the AP; determining, with the AP via beamforming of a fixed antenna array of the AP, whether an angle of the wireless device relative to the fixed antenna array is within a first predetermined range; determining, with the AP, whether a received signal strength between the AP and the wireless device is within a second predetermined range; and granting, with the AP, the wireless device access to a network through the AP when it is determined that the angle of the wireless device relative to the fixed antenna array is within the first predetermined range and the received signal strength is within the second predetermined range.