A feed circuit for feeding an antenna includes: a first coupler including a first pair of opposing conductive elements; a second coupler including a second pair of opposing conductive elements; a third coupler including a third pair of opposing conductive elements; a delay line; first terminals configured to connect to the antenna; second terminals connected to a ground reference; and a feed terminal connected to the first coupler and configured to receive at least one of a transmit signal to be transmitted from the antenna or a combined received signal from the antenna. The first terminals are connected to the second coupler and the third coupler and configured to output a signal at different phases to conductive elements of the antenna. The second terminals are connected to the first coupler, the second coupler and the third coupler.

An apparatus caused to, in respect of determination of a direction towards an object in a space, the object having a tag capable of emitting a wireless signal for reception by a locator of a positioning system configured to determine the direction towards the tag based on the wireless signal, based on object orientation information comprising the orientation of the object as viewed by a camera capturing visual imagery of the space and predetermined tag position information comprising the position on the object where the tag is attached, provide for determination of at least whether or not the object is oriented such that the tag substantially faces the locator and thereby control of the positioning system in the determination of at least a viability of the wireless signal for determining the direction towards the object, the tag substantially facing the locator indicative of the viability of the wireless signal.

A method for identifying transmitter usage characteristics of at least one transmitter. The method includes the procedures of receiving by an array of dual polarized antennas, transmissions from a plurality of transmitters. Each one of the transmitters transmits over the same frequency band and according to the same transmission protocol. Each one of the transmitters is associated with unique multi-access information. The method further includes the procedure of receiving a control transmission from a base station. The base station employs the protocol. The control transmission at least includes a plurality of unique multi-access information respective of the transmitters. The method also includes the procedure of associating between each one of the transmitters and the respective multi-access information and identifying transmitter usage characteristics of at least one selected transmitter according to the received transmission therefrom. The transmitter usage characteristics include transmitter location characteristics and transmission characteristics.

Provided is a wireless positioning calibration system, including a plurality of transmission base stations, at least one sniffer base station and a positioning server. The at least one sniffer base station receives a plurality of channel state information (CSI) transmitted by the plurality of transmission base stations. The positioning server receives the plurality of CSI transmitted by the at least one sniffer base station. The positioning server calculates a phase error and an antenna spacing error generated by the at least one sniffer base station by means of the plurality of CSI, and compensates the phase error and the antenna spacing error. A wireless positioning calibration method is also provided.

A system and method for determining an Angle of Arrival (AOA) for frequency modulated communications. The system may include first and second antennas spaced apart from each other by a distance, and configured to receive wireless communications in the form of a modulated signal. The system may determine a phase difference between the received signals based on one or more samples of a dedicated portion of the received signals, where one or more aspects of the dedicated portion is variable.

A system and method for determining an Angle of Arrival (AOA) for frequency modulated communications. The system may include first and second antennas spaced apart from each other by a distance, and configured to receive wireless communications in the form of a frequency modulated signal. The system may determine a phase difference between the received signals irrespective of the modulations in the signal, thereby facilitating determining an AOA.

The present disclosure obtains a correction value that corrects measurement angle error signals more accurately than conventional methods even in a case where a radio wave signal-to-noise ratio is low, and thus tracks a communication counterpart more accurately than the conventional methods.

The present disclosure includes a program controller 28 that generates a command value of an orientation direction of an antenna 1 and outputs the generated command value to an antenna drive controller 27, the command value being changed in accordance with a predetermined change scenario 54; a correction value calculator 32 that calculates a phase correction value , based on at least three pieces of error measurement data 55 including (i) an arrival direction error obtained from a sum signal and a difference signal of reception signals, the arrival direction error representing a difference between the orientation direction and an arrival direction being a direction from which the radio waves come and arrive and (ii) an orientation direction actual measurement value being an actual measurement value of the orientation direction when the arrival direction error is obtained, the phase correction value being an angle by which the arrival direction error is rotated; and a tracking controller 33 that outputs, to the antenna drive controller 27, as the command value, a value obtained by adding the arrival direction error corrected based on the phase correction value to the orientation direction actual measurement value.

A method for radio direction finding using a direction finding system having an antenna, a magnetic field sensor and a control unit, the method comprising: receiving a radio frequency signal of at least one emitter via the antenna by the control unit obtaining a received signal; receiving a magnetic measurement value of the magnetic field at the direction finding system via the magnetic field sensor; correcting the magnetic measurement value obtaining a corrected magnetic measurement value; correcting the received signal obtaining a corrected signal; and determining the precise bearing of the emitter based on the corrected received signal and the corrected magnetic measurement value. Further, a direction finding system and a platform are disclosed.

The invention relates to a method for establishing the presence of a misalignment of at least one sensor within a sensor group with two or more sensors which detects objects in the surroundings of a motor vehicle, wherein at least two of the sensors differ from each other in their measuring principle and the measurement signals from the sensors are compared with each other.

A method measures an angle of arrival (AOA) of an incoming signal using m separate antennas coupled via a switch with a single receiving device. The switch sequentially supplies the incoming signal to the receiver. A sampling of the incoming signal as received at the antennas has a sampling rate and cycle time performed in repetitive cycles. The receiver generates baseband signals with in-phase and quadrature components from the incoming signal and forwarding to each analog-to-digital converter to provide digitized samples. A signal processor is coupled to the respective analog-to-digital converter to analyze the digitized signals and to determine the angle of arrival of the incoming signal. The resulting phase error is compensated by sampling and signal processing. A device operates according to the method and an arrangement with a mobile transmitter and a device and software for locating the mobile transmitter by the device.