Using a phase interferometry method which utilizes both amplitude and phase allows the determination and estimation of multipath signals. To determine the location of an object, a signal that contains sufficient information to allow determination of both amplitude and phase, like a packet that includes a sinewave portion, is provided from a master device. A slave device measures the phase and amplitude of the received packet and returns this information to the master device. The slave device returns a packet to the master that contains a similar sinewave portion to allow the master device to determine the phase and amplitude of the received signals. Based on the two sets of amplitude and phase of the RF signals, the master device utilizes a fast Fourier transform or techniques like multiple signal classification to determine the indicated distance for each path and thus more accurately determines a location of the slave device.

A measurement system for identifying a source direction of a wireless electromagnetic emitter signal is described. The measurement system is a radio frequency measurement system that comprises a rotary antenna and an analyzer or analysis unit being connected to the rotary antenna in a signal transmitting manner. The rotary antenna is a directional antenna and configured to receive the emitter signal and to forward the received emitter signal to the analysis unit for further processing. The measurement system is configured to gather a momentary position of the rotary antenna. The analysis unit is configured to determine a momentary frequency spectrum of the emitter signal and to combine the momentary frequency spectrum with the momentary position to generate source direction data comprising information on both the momentary frequency spectrum of the emitter signal and the momentary position of the rotary antenna. Moreover, a method for identifying a source direction of a wireless electromagnetic emitter signal is described.

A measurement system for identifying a source direction of a wireless electromagnetic emitter signal is described. The measurement system is a radio frequency measurement system that comprises a rotary antenna and an analyzer or analysis unit being connected to the rotary antenna in a signal transmitting manner. The rotary antenna is a directional antenna and configured to receive the emitter signal and to forward the received emitter signal to the analysis unit for further processing. The measurement system is configured to gather a momentary position of the rotary antenna. The analysis unit is configured to determine a momentary frequency spectrum of the emitter signal and to combine the momentary frequency spectrum with the momentary position to generate source direction data comprising information on both the momentary frequency spectrum of the emitter signal and the momentary position of the rotary antenna. Moreover, a method for identifying a source direction of a wireless electromagnetic emitter signal is described.

An improved two-way tagging tracking and locating system uses time of arrival (TOA), Doppler, and angle of arrival (AOA) in conjunction with remote tags and a locator. The locator's antenna is tethered to a central point, and moved in a constrained motion so that it describes a roughly circular horizontal path. The locator transmits and receives sets of complex radio sequences to/from the tag(s) so that the tag(s) emit signals which are phase, chip, and symbol coherent with the received locator signals. This enables the locator to determine the distances and Doppler shifts between itself and the tag(s) at various positions in its path such that, by post correlation processing of complex captured signal sequences, aims a virtual phased array antenna at the tag(s), resulting in enhanced distance and direction measurements. The angular position of the orbiting locator's antenna may be measured using an electronic compass packaged with the antenna.

An improved two-way tagging tracking and locating system uses time of arrival (TOA), Doppler, and angle of arrival (AOA) in conjunction with remote tags and a locator. The locator's antenna is tethered to a central point, and moved in a constrained motion so that it describes a roughly circular horizontal path. The locator transmits and receives sets of complex radio sequences to/from the tag(s) so that the tag(s) emit signals which are phase, chip, and symbol coherent with the received locator signals. This enables the locator to determine the distances and Doppler shifts between itself and the tag(s) at various positions in its path such that, by post correlation processing of complex captured signal sequences, aims a virtual phased array antenna at the tag(s), resulting in enhanced distance and direction measurements. The angular position of the orbiting locator's antenna may be measured using an electronic compass packaged with the antenna.

A direction finder antenna system and method are described. The direction finder antenna system comprises a rotatable platform comprising at least two antenna units at selected distance between them, a motor configured for moving the rotatable platform at a motion pattern, and a signal collection circuit configured for receiving data on signal portions collected by said at least two antenna units with respect to different angular positions of said at least two antenna units. The signal collection circuit generates output data indicative of direction of origin of collected signal.

Provided are a system and a method for determining an angle. The method includes: determining differences between signal strengths of incident waves received by a first directional antenna of an anchor node from a tested node and signal strengths of incident waves received by a second directional antenna of the anchor node from the tested node at multiple angles, wherein the first directional antenna and the second directional antenna are mounted at a same point, and an area formed by the first directional antenna is partially superposed with an area formed by the second directional antenna; and taking an angle corresponding to a minimum difference in the differences as an angle between a line connecting the anchor node and the tested node and a horizontal reference line. The present technical solution achieves the technical effect of positioning a target accurately when the positioning device is low in complexity.

Provided are a system and a method for determining an angle. The method includes: determining differences between signal strengths of incident waves received by a first directional antenna of an anchor node from a tested node and signal strengths of incident waves received by a second directional antenna of the anchor node from the tested node at multiple angles, wherein the first directional antenna and the second directional antenna are mounted at a same point, and an area formed by the first directional antenna is partially superposed with an area formed by the second directional antenna; and taking an angle corresponding to a minimum difference in the differences as an angle between a line connecting the anchor node and the tested node and a horizontal reference line. The present technical solution achieves the technical effect of positioning a target accurately when the positioning device is low in complexity.

Disclosed is a hybrid direction detection apparatus and method that may perform a precise direction detection through a one-time rotation of a log period (LP) antenna and a one-time phase difference measurement of a dipole antenna and may remove an ambiguity error of the LP antenna by two dipole antennas spaced apart by a distance of about 0.5 by finding an approximate direction using the LP antenna that is a directional antenna, by measuring a phase difference between arrival waves using two baselines including two dipole antenna in the corresponding direction, and thereby precisely finding a final direction.

Disclosed is a hybrid direction detection apparatus and method that may perform a precise direction detection through a one-time rotation of a log period (LP) antenna and a one-time phase difference measurement of a dipole antenna and may remove an ambiguity error of the LP antenna by two dipole antennas spaced apart by a distance of about 0.5 by finding an approximate direction using the LP antenna that is a directional antenna, by measuring a phase difference between arrival waves using two baselines including two dipole antenna in the corresponding direction, and thereby precisely finding a final direction.