A direction finding method of determining bearings of radio signals by a direction finding system is described. Further, a direction finding system for determining bearings of radio signals is described.

One embodiment provides a line of sight detector. The line of sight detector includes a first TeraFET (field effect transistor) including a first source, a first drain, a first gate, and a first channel having a first end and a second end. The line of sight detector further includes a first source antenna coupled to the first source; a first drain antenna coupled to the first drain; and a third antenna. Each antenna is configured to receive an incident radiation signal having a frequency in a sub terahertz or a terahertz frequency range. Each antenna is positioned a respective distance from each other antenna. Each distance is less than one wavelength of the incident radiation signal.

One embodiment provides a line of sight detector. The line of sight detector includes a first TeraFET (field effect transistor) including a first source, a first drain, a first gate, and a first channel having a first end and a second end. The line of sight detector further includes a first source antenna coupled to the first source; a first drain antenna coupled to the first drain; and a third antenna. Each antenna is configured to receive an incident radiation signal having a frequency in a sub terahertz or a terahertz frequency range. Each antenna is positioned a respective distance from each other antenna. Each distance is less than one wavelength of the incident radiation signal.

Techniques for determining a location of a client device using recursive phase vector subspace estimation are described. One technique includes receiving a plurality of angle-of-arrival (AoA) measurements from a plurality of access points (APs). Each AoA measurement includes a plurality of entries for phase values measured from a signal received from a client device at the plurality of APs. At least one AoA measurement of the plurality of AoA measurements that includes at least one of: (i) one or more entries with missing phase values and (ii) one or more entries with erroneous phase values is identified, based on a recursive phase estimation. The plurality of AoA measurements are updated based on the identified at least one AoA measurement. The location of the client device is determined, based on the updated plurality of AoA measurements.

Techniques for determining a location of a client device using recursive phase vector subspace estimation are described. One technique includes receiving a plurality of angle-of-arrival (AoA) measurements from a plurality of access points (APs). Each AoA measurement includes a plurality of entries for phase values measured from a signal received from a client device at the plurality of APs. At least one AoA measurement of the plurality of AoA measurements that includes at least one of: (i) one or more entries with missing phase values and (ii) one or more entries with erroneous phase values is identified, based on a recursive phase estimation. The plurality of AoA measurements are updated based on the identified at least one AoA measurement. The location of the client device is determined, based on the updated plurality of AoA measurements.

An electronic device includes an indoor positioner and a positioning engine server. The indoor positioner has an antenna array including a plurality of antenna units. The indoor positioner divides the antenna units into multiple antenna unit groups, receives a wireless signal from user equipment at each time point via the antenna unit groups, and calculates a plurality of angles of arrival (AOA) corresponding to the antenna unit groups at each time point. The positioning engine server receives and stores the angles of arrival corresponding to the antenna unit groups at each time point, and filters the angles of arrival according to the angle sizes of the angles of arrival corresponding to the antenna unit groups at each time point stored in an observation period.

An electronic device includes an indoor positioner and a positioning engine server. The indoor positioner has an antenna array including a plurality of antenna units. The indoor positioner divides the antenna units into multiple antenna unit groups, receives a wireless signal from user equipment at each time point via the antenna unit groups, and calculates a plurality of angles of arrival (AOA) corresponding to the antenna unit groups at each time point. The positioning engine server receives and stores the angles of arrival corresponding to the antenna unit groups at each time point, and filters the angles of arrival according to the angle sizes of the angles of arrival corresponding to the antenna unit groups at each time point stored in an observation period.

The invention discloses a method for estimating the direction-of-arrival of a coprime array based on virtual domain statistics reconstruction of single-bit quantized signal. The realization steps are as follows: arranging a coprime array and a single-bit analog-to-digital converter at a receiving end; calculating equivalent virtual signal corresponding to a single-bit receipt signal of the coprime array; constructing a virtual domain augmented covariance matrix of an initialized single-bit quantized signal; designing, based on statistical correlation analysis between statistics of the single-bit quantized signal and the original unquantized signal, an optimization problem based on virtual domain statistics reconstruction of quantized signal; and performing direction-of-arrival estimation by utilizing the virtual domain augmented covariance matrix corresponding to the optimized single-bit quantized signal.

A receiver is disclosed. The receiver includes one or more antennas receiving signals from a transmitter including one or more antennas, and at least one RF chain generating digital samples based on the received signals. Either A) the signals are transmitted by a single antenna of the transmitter and are received by multiple antennas of the receiver, or B) the signals are transmitted by multiple antennas of the transmitter and are received by a single antenna of the receiver. The receiver also includes a controller determining a plurality of groups of digital samples to use for calculating estimates of an AoA or AoD of the received signals, calculate estimates of AoA or AoD based on the groups of digital samples, select a subset of the estimates, and calculate a measured AoA or AoD based on the selected subset of estimates.

A receiver is disclosed. The receiver includes one or more antennas receiving signals from a transmitter including one or more antennas, and at least one RF chain generating digital samples based on the received signals. Either A) the signals are transmitted by a single antenna of the transmitter and are received by multiple antennas of the receiver, or B) the signals are transmitted by multiple antennas of the transmitter and are received by a single antenna of the receiver. The receiver also includes a controller determining a plurality of groups of digital samples to use for calculating estimates of an AoA or AoD of the received signals, calculate estimates of AoA or AoD based on the groups of digital samples, select a subset of the estimates, and calculate a measured AoA or AoD based on the selected subset of estimates.