The invention relates to a method and a device for estimating an angle of arrival of an incident radio signal in relation to a predetermined reference direction by using a set of N receiving paths comprising at least one directional antenna pointing in N different receiving directions, wherein only one sub-set of at least two receiving paths with adjacent antenna directions in said set of antennas delivers a measured power at reception. The device comprises modules suitable for: determining a number of receiving paths delivering a measured power forming said sub-set, and a reference index corresponding to a first receiving path in a direction in which extends the set of antenna directions of said sub-set; selecting the measured powers and obtaining a value to attribute to the non-measured powers to form a completed power signal; by applying a discrete Fourier transform (DFT) to said completed power signal, calculating at least one transformed value among the transformed values corresponding to a first, second, and third frequency line of the DFT; and, using the transformed value(s), applying an estimator of the angle of arrival, depending on the reference index.

A direction-finding antenna includes at least a first set of radiating elements configured to radiate at least a first wavelength (λ.sub.1) and a second set of radiating elements configured to radiate at a second wavelength (λ.sub.2) that is shorter than the first wavelength (λ.sub.1). The first set of radiating elements defines a first circle having a first radius. The second set of radiating elements defines a second circle having a second radius that is smaller than the first radius of the first circle. The direction-finding antenna further includes a transmission line-based multiplexer configured to selectively couple the first set of radiating elements or the second set of radiating elements to a radio frequency (RF) feed line, or a plurality of switches configured to selectively couple selected radiating elements of the first set of radiating elements or the second set of radiating elements to the RF feed line.

A direction-finding antenna includes at least a first set of radiating elements configured to radiate at least a first wavelength (λ.sub.1) and a second set of radiating elements configured to radiate at a second wavelength (λ.sub.2) that is shorter than the first wavelength (λ.sub.1). The first set of radiating elements defines a first circle having a first radius. The second set of radiating elements defines a second circle having a second radius that is smaller than the first radius of the first circle. The direction-finding antenna further includes a transmission line-based multiplexer configured to selectively couple the first set of radiating elements or the second set of radiating elements to a radio frequency (RF) feed line, or a plurality of switches configured to selectively couple selected radiating elements of the first set of radiating elements or the second set of radiating elements to the RF feed line.

Systems, methods, and apparatus cause a first wireless device to transmit to a plurality of locator devices, an extended signal including a first segment and second segment. The first segment includes an indication for each of the plurality of locator devices to listen for a change in the extended signal from the first segment to the second segment. The second segment includes an indication for each of the plurality of locator devices to rotate through a plurality of antennas to receive the second segment via the plurality of antennas. Responsive to the transmitting of the extended signal, receiving direction data from each of the plurality of locator devices.

Systems, methods, and apparatus cause a first wireless device to transmit to a plurality of locator devices, an extended signal including a first segment and second segment. The first segment includes an indication for each of the plurality of locator devices to listen for a change in the extended signal from the first segment to the second segment. The second segment includes an indication for each of the plurality of locator devices to rotate through a plurality of antennas to receive the second segment via the plurality of antennas. Responsive to the transmitting of the extended signal, receiving direction data from each of the plurality of locator devices.

Directional antennas comprising substantially identical radiation patterns separated in a horizontal plane by an index angle. A line of bearing to an emitter is determined by a ratio of the power level of an EM signal received by the directional antennas and comparing it to a lookup table to determine an angle off of the boresight of the directional antenna with the highest received power level of the EM signal toward the directional antenna with the second-highest received power level of the EM signal that the emitter of the EM signal is located.

A radio presence-advertising signal (PAS) a PAS emitter is simultaneously received at two or more co-located directional antennas that are coupled to respective radio receivers. The antennas have reception sensitivity lobes that overlap to define a region of interest at the overlap. Substantially cotemporaneous signal strength indications are obtained from the radio receivers. A difference signal representative of a difference between two of the obtained signal strength indications of the respective antennas is generated. An average signal representative of a running average of two or more of the obtained signal strength indications is generated and used to produce a normalized confidence indicator indicating a level of confidence that the PAS emitter is disposed inside (e.g., centered in) the region of interest or alternatively indicating a level of confidence that the PAS emitter is disposed outside the region of interest. Action is taken or avoided based on the confidence signal.

Systems, methods, and apparatus cause a first wireless device to transmit to a plurality of locator devices, an extended signal including a first segment and second segment. The first segment includes an indication for each of the plurality of locator devices to listen for a change in the extended signal from the first segment to the second segment. The second segment includes an indication for each of the plurality of locator devices to rotate through a plurality of antennas to receive the second segment via the plurality of antennas. Responsive to the transmitting of the extended signal, receiving direction data from each of the plurality of locator devices.

Systems, methods, and apparatus cause a first wireless device to transmit to a plurality of locator devices, an extended signal including a first segment and second segment. The first segment includes an indication for each of the plurality of locator devices to listen for a change in the extended signal from the first segment to the second segment. The second segment includes an indication for each of the plurality of locator devices to rotate through a plurality of antennas to receive the second segment via the plurality of antennas. Responsive to the transmitting of the extended signal, receiving direction data from each of the plurality of locator devices.

A transmitting device and a receiving device, which can carry out measurements, are disclosed together with a method for estimating an angle of departure of radio waves. The receiving device sets an equal phase of each antenna in a uniform circular array antenna, receives a transmitted millimeter wave signal, and calculates angle of arrival (AOD) of the millimeter wave signal, thus simplifying the steps for estimating AOD.