A storage medium-compatible communications unit, a phase detection unit, a parameter acquisition section and a location detection section are provided. The storage medium-compatible communications unit communicates with a storage medium by wireless using electromagnetic waves at a predetermined frequency. The phase detection unit detects phases of signals received from the storage medium. The parameter acquisition section acquires a distance detection parameter to be used in detecting a storage medium distance from a first position of an antenna to the storage medium. The first position is a position in a range of positions of the antenna from which the distance to the storage medium is shortest. The distance detection parameter is a value set in accordance with a positional relationship between the first position and a second position. The second position is a position of the antenna in the range of positions of the antenna that is different from the first position. The location detection section detects the storage medium distance, using a first phase detected by the phase detection unit at the first position, a second phase detected by the phase detection unit at the second position, and the distance detection parameter acquired by the parameter acquisition section. The location detection section identifies the first position at a time at which a trend of changes of phase detected by the phase detection unit in association with movement of the antenna reverses.

The invention discloses a golf ball tracking system, which includes a distributed sensor and processor system adapted to simultaneously track the trajectories of multiple golf balls hit by one of more golfers. The system is adapted to keep track of the location of the golfers to enable the allocation of shots to the correct golfer. The system is operated at a golf driving range, where multiple players can hit balls from anywhere within a designated area and/or fixed hitting bay locations. Multilateration is used to determine the location of multiple targets in 3D space, based on the reported range and Doppler from distributed radar sensors.

This disclosure enables various technologies involving various actions based on tracking an object via a plurality of distance sensors, without synchronizing carrier waves of the distance sensors or without employing a PLL technique on the distance sensors.

This disclosure provides systems, methods and apparatus, including computer programs encoded on computer storage media, for multistatic radar communications. In some implementations, a transmitting device may transmit, to a receiving device, a radar alert frame followed by a codeword and one or more radar pulses. The radar pulses are transmitted, using beamforming, in a number of directions. The timing information indicates a timing offset or delay between one or more codewords of the codeword sequence and the beginning of the radar pulses. The receiving device may detect one or more codewords of the codeword sequence and an echo of at least one of the radar pulses, and determine the time at which the corresponding pulse was transmitted by the transmitting device. The receiving device may compare the timing of the echo with the timing of the transmitted pulse to determine a relative distance of an object that produced the echo.

A system identifies and localizes an object. The system contains a bistatic FMCW radar sensor system having two FMCW radar sensors and is configured to operate coherently or quasi-coherently and to emit a series of repeating ramp signals. An active RFID transponder is disposed on an object to be identified and to be localized and is configured to produce a modulated bistatic backscatter signal. A ramp signal sent out by the radar sensors at a ramp repetition frequency is modulated with an amplitude modulation signal, the modulation frequency is less than half the ramp repetition frequency. An evaluation unit establishes an association between a beat frequency and the modulation frequency of the active RFID transponder, which modulation frequency is already known, on the basis of the modulated bistatic backscatter signal by two Fourier transforms of the modulated backscatter signal according to the frequency and to the amplitude.

An embodiment of the disclosure provides an apparatus that include a communication module, a memory, a processor operatively connected to at least one of the communication module or the memory. The processor may be configured to perform UWB communication with a plurality of anchors included in a vehicle via the communication module according to a first scheme, to determine whether a distance to the vehicle falls within a predetermined distance by measuring the distance via the UWB communication, to determine whether a predetermined condition is satisfied if the distance falls within the predetermined distance, and if the predetermined condition is satisfied, to change the UWB communication scheme from the first scheme to a second scheme. Other embodiments are possible.

A system and method for locating radio-frequency identification tags within a predetermined area. The method can incorporate sub-threshold superposition response mapping techniques, alone, or in combination with other methods for locating radio-frequency identification tags such as but not limited to time differential on arrival (TDOA), frequency domain phase difference on arrival (FD-PDOA), and radio signal strength indication (RSSI). The system can include a plurality of antennas dispersed in a predefined area; one or more radio-frequency identification tags; a radio-frequency transceiver in communication with said antennas; a phase modulator coupled to the radio-frequency transceiver; and a system controller in communication with said transceiver and said phase modulator. Calibration techniques can be employed to map constructive interference zones for improved accuracy.

A method of collision warning using broad antenna pattern ultra-wide band (UWB) radar includes emitting a first radar ping from a broad beam UWB antenna and receiving a first return signal identifying an object. A first hemisphere with a first radius is determined for the object. A second ping, second return and second hemisphere is defined for the object. At the intersection of the hemispheres, an object ring is defined. The radius of the object ring is compared with the radius of a collision cylinder (e.g., representing a safe distance around a system or device, such as a drone). The object may be identified as posing a collision threat when the radius of the object ring is smaller than the radius of the collision cylinder.

A wearable device is described that is configured to alert a subject prior to encountering an obstacle. The subject may be visually-impaired. The device includes: a mobile transceiver tag adapted to be worn by a subject within a designated area (e.g., a swimming pool); three or more stationary transceiver beacons in spaced apart, fixed positions; a wearable signal output device (e.g., headset); and a processor with software that can calculate the subject's position relative to one or more obstacles (e.g., end of swimming lane) and sends a left, right, or reverse signal to the signal output device.

Methods and systems for mapping boundaries of a given environment by a processor of a computer system, the method comprising: determining a trajectory of the body in the given environment over the given time period; and determining, based on the trajectory of the body in the given environment, one or more of an outer boundary of the given environment, and an inner boundary of the given environment. Methods and systems for mapping functionalities of a given environment executable by a processor of a computer system, the method comprising determining a pattern of movement of a body in the given environment in a given time period; and determining a functional identity of at least one zone in the given environment based on the pattern of movement of the body to obtain a mapped given environment.