An electronic device including a sound receiver and a processor is provided. The sound receiver receives a sound signal provided by a sound generator. When the processor determines that an obstacle is blocked between the electronic device and the fixed device, the processor estimates a virtual position of the electronic device at a current time according to previous movement information and a previous position of the electronic device. The virtual position has a shortest path between a boundary position of the obstacle and the sound generator. The processor obtains a first relative distance between the electronic device and the boundary position according to the sound signal received by the sound receiver and the boundary position. The processor calculates a relative velocity and a relative acceleration of the electronic device relative to the fixed device at the current time according to the sound signal and the first relative distance.

An electronic device including a sound receiver and a processor is provided. The sound receiver receives a sound signal provided by a sound generator. When the processor determines that an obstacle is blocked between the electronic device and the fixed device, the processor estimates a virtual position of the electronic device at a current time according to previous movement information and a previous position of the electronic device. The virtual position has a shortest path between a boundary position of the obstacle and the sound generator. The processor obtains a first relative distance between the electronic device and the boundary position according to the sound signal received by the sound receiver and the boundary position. The processor calculates a relative velocity and a relative acceleration of the electronic device relative to the fixed device at the current time according to the sound signal and the first relative distance.

To make it possible to estimate the position of a sound source resulting from a wearing displacement, even in the case where the wearing displacement occurs in a wearable device.

A sound source position estimation device according to the present disclosure includes: a spectrum acquisition unit configured to acquire a frequency spectrum of a sound source on the basis of a sound obtained by a plurality of microphones provided for a ring-like wearable device; a distance computing unit configured to compute respective distances from the plurality of microphones to the sound source on the basis of the frequency spectrum; and a sound source position computing unit configured to, approximating the ring-like wearable device to a circle and assuming that the sound source is located on a cylindrical surface including the ring-like wearable device, obtain an intersection between the cylindrical surface and spherical surfaces whose radii are the respective distances to compute a position of the sound source.

Systems and methods for location estimation and tracking for passive RFID and wireless sensor networks in accordance with embodiments of the invention are disclosed. In one embodiment, a process for obtaining location information using an RFID reader system includes transmitting a combined interrogation and ranging signal from a plurality of antennas, where the ranging signal is a pseudorandom signal, receiving a backscattered return signal from an RFID tag at one or more receive antennas, extracting an information signal from the return signal and decoding the information signal to obtain RFID tag data, extracting a received ranging signal from the return signal, and estimating a range to the RFID tag based upon correlation between the ranging signal and the received ranging signal.

Systems and methods for location estimation and tracking for passive RFID and wireless sensor networks in accordance with embodiments of the invention are disclosed. In one embodiment, a process for obtaining location information using an RFID reader system includes transmitting a combined interrogation and ranging signal from a plurality of antennas, where the ranging signal is a pseudorandom signal, receiving a backscattered return signal from an RFID tag at one or more receive antennas, extracting an information signal from the return signal and decoding the information signal to obtain RFID tag data, extracting a received ranging signal from the return signal, and estimating a range to the RFID tag based upon correlation between the ranging signal and the received ranging signal.

A method for measuring a distance between a first device and a second device, the method may include playing, by a first sound output unit, a first correlation tone; receiving, by a first sound sensing unit, the first correlation tone; detecting a start point of a reception of the first correlation tone; receiving, by the first sound sensing unit, a second correlation tone; wherein the second correlation tone is played by a second sound output unit in response to a reception, by a second sound sensing unit, of the first correlation tone; detecting a start point of a reception of the second correlation tone; receiving, by the first sound sensing unit, information about a processing time of the second device; calculating, by a first processing unit, a timing difference between (i) the start point of the reception of the second correlation tone, and (ii) the start point of the reception of the first correlation tone; and determining the distance between the first device and the second device based on a difference between the timing difference and the processing time of the second device; wherein the first processing unit, the first sound sensing unit and the first sound output unit belong to the first device; and wherein the second sound sending unit and the second sound output unit belong to the second device.

In order to accurately determine the location of an electronic device in an environment, a computer selects a set of received-signal-strength (RSS) values based on wireless communication between the electronic device and access points in sub-regions of the environment. This set includes a largest RSS value associated with a sub-region and at least two RSS values associated with neighboring sub-regions. Then, the computer calculates pairwise distance estimates of the location of the electronic device in the environment based on predefined locations of the access points associated with the set, one or more differences of pairs of RSS values in the set and a predetermined path-loss factor in the environment, where a given pair of RSS values includes the largest RSS value and one of the at least two RSS values. Furthermore, the computer determines the location of the electronic device in the environment based on the pairwise distance estimates.

In order to accurately determine the location of an electronic device in an environment, a computer selects a set of received-signal-strength (RSS) values based on wireless communication between the electronic device and access points in sub-regions of the environment. This set includes a largest RSS value associated with a sub-region and at least two RSS values associated with neighboring sub-regions. Then, the computer calculates pairwise distance estimates of the location of the electronic device in the environment based on predefined locations of the access points associated with the set, one or more differences of pairs of RSS values in the set and a predetermined path-loss factor in the environment, where a given pair of RSS values includes the largest RSS value and one of the at least two RSS values. Furthermore, the computer determines the location of the electronic device in the environment based on the pairwise distance estimates.

Embodiments of the present disclosure provide a positioning system and positioning method. A reverse calibrator for respectively calibrating relative coordinates of at least three ultrasound generators; a processor for generating a carrier signal, multiplying the carrier signal with a spread spectrum pseudo random code to obtain ranging signal, controlling each ultrasound generator to emit ranging signal, and extracting acoustic characteristic parameter of the ranging signals; a device being positioned for capturing ranging signals emitted by each generator, extracting acoustic characteristic parameter of each of the captured ranging signals; determining an ultrasonic delay time of each ultrasonic ranging signal; calculating relative coordinates of the device.

A system for tracking a position on a rig site may include a plurality of static beacons of defined positions on the rig site configured to transmit reference signals at a selected triggering time for transmission; at least one moveable receiver at a first location on the rig site configured to receive the reference signals from the plurality of static beacons, determine the reception time of signal, and transmit reception information to a master node via a communication channel; wherein the master node is at a location on the rig site with a reference base time, wherein the master node receives the defined positions and reference times of the plurality of static beacons, and wherein the system is configured to, based on the reception information, determine signal travel times between the static beacons and the at least one moveable receiver, determine the distances between the static beacon and the at least one moveable receiver based on a travel time of the reference signals, and determine a position of the first location.