A radar system, apparatus, architecture, and method are provided for generating a mono-static virtual array aperture by using a radar control processing unit to construct a mono-static MIMO virtual array aperture from radar signals transmitted orthogonally from transmit antennas and received at each receive antennas, and to construct a mono-static MIMO forward difference virtual array aperture by performing forward difference co-array processing on the mono-static MIMO virtual array aperture to fill in holes in the mono-static MIMO virtual array aperture, thereby mitigating or suppressing spurious sidelobes caused by gaps or holes in the mono-static MIMO virtual array aperture.

A radio-frequency method for range finding includes modulating a reference signal having an intermediate frequency to a downlink signal having a carrier frequency using a clock signal. The downlink signal is transmitted to a tag using a transceiver. An uplink signal backscattered from the tag is received and demodulated using the clock signal. The uplink signal has a frequency that is a harmonic of the carrier frequency. A distance between the tag and the transceiver is calculated based on a phase of the demodulated uplink signal. A system for range finding includes a transceiver and a processor. The transceiver modulates a reference signal to a downlink signal and transmits the downlink signal. The transceiver receives and demodulates an uplink signal. The processor is configured to receive the demodulated uplink signal and calculate a distance between the tag and the transceiver using a phase of the demodulated uplink signal.

Apparatus and associated methods relate to a method of non-contact motion detection. A one-dimensional optical sensor detects motion of a target or objects on a conveyor belt through a continuous measurement of targets or objects and a real-time comparison of the pixel images captured by the one-dimensional optical sensor. In an illustrative embodiment, a one-dimensional sensor may be configured to determine motion of objects based on changes to the captured intensities of pixel images over time. The sensor may continually capture photoelectric pixel images and compare a current pixel image with a previous pixel image to determine a frame differential image value. The frame differential image value is evaluated against a predetermined threshold over a predetermined time period. Based on the evaluation, a signal is output indicating whether the objects on the conveyor belt are moving or jammed.

In some example embodiments, there is provided a tag. The tag may include an antenna configured to receive a first radio frequency signal and to reradiate a second radio frequency signal; and an ultrasonic transducer coupled to the antenna, wherein an ultrasound signal received by the ultrasonic transducer causes a variation of at least one property of the ultrasonic transducer, wherein the variation of the at least one property imparts a modulation onto at least a portion of the first radio frequency signal, and wherein the modulated first radio frequency signal is reradiated by the antenna as the second radio frequency signal. Related system, methods, and articles of manufacture are also disclosed.

The present disclosure relates to a vehicle. The vehicle includes a first set of cameras, including a first subset of cameras facing to the front of the vehicle; a second set of cameras, with focal lengths less than those of the first set of cameras, the second set of cameras including a second and a third subset of cameras, the second subset of cameras facing to the front of the vehicle, and third subset of cameras facing to a side front and/or a side of the vehicle; and a third set of cameras, with focal lengths less than those of the second set of cameras, the third set of cameras including a fourth and a fifth subset of camera, the fourth subset of cameras facing to the front of the vehicle, and the fifth subset of camera facing to the side front and/or side of the vehicle.

In the present disclosure, a radar system is configured to interact with beacons that shift the phase of a received radar transmission to generate a phase shifted response signal. Phase shifters are designed to assign specific frequency responses to identify target locations. The radar module transmits at a modulated signal at first frequency, each beacon receives the radar transmission, phase shifts the signal and returns the phase shifted signal. Where two or more beacons are used, each will apply a different phase shift to the received radar transmission, wherein the frequency identifies the specific beacons. In a radar system, the modulated transmission signal is compared to the returned phase shifted signal to determine a frequency difference between the two signals.

An estimation method includes: transmitting transmission signals using M transmission antenna elements; receiving reception signals by N reception antenna elements; calculating, from the reception signals, a first matrix whose components are complex transfer functions indicating propagation characteristics between the transmission antenna elements and the reception antenna elements; estimating, using the first matrix, a position and an orientation of a living body relative to an estimation device; when the estimated position is in a first identification region and the estimated orientation is in a predetermined range from a first direction, identifying the living body based on time waveforms of the reception signals and a first training signal which is obtained in advance in the first identification region and corresponds to the living body; and adding, as an identification region for identifying the first living body identified, a new identification region based on an estimated position of the first living body identified.

An object position-measuring device, a method thereof, and a system thereof are proposed. The object position-measuring device, method thereof, and system thereof are for measuring a position of an object by using a plurality of wireless signals indoors. In the object position-measuring device, method thereof, and system thereof, respective distances from the position-measuring device and first and second wireless communication devices to the object are calculated by using respective travel times of the wireless signals respectively transmitted from the position-measuring device and the first and second wireless communication devices and the wireless signals received after being reflected from the object, whereby the position of the object is measured by using the calculated distances.

An RFID detector suitable for use in a passive RFID tag system that employs frequency hopping spread spectrum (FHSS) operation obtains an indication of at least one characteristic of a CW RF signal employing a hopped-to carrier frequency that is being transmitted from an RFID tag reader, e.g., for use in activating the RFID tag to be located, the indication of the characteristic being obtained based on a signal that is received from a source other than the RFID detector. The RFID detector may use the obtained indication of the characteristic of the CW RF signal to determine at least one position related parameter for the RFID tag. A location, e.g., of the tag, of a group of tags, of the RFID detector, or of another RFID detector, may be determined based on the position parameter.

This document describes techniques and systems for independent transmit and receive channel calibration for multiple-input multiple-output (MIMO) systems. Antenna responses are collected from each virtual channel of a MIMO system at an angle respective to an object. The transmit components and the receive components of the virtual channels are separated and organized into vectors (one for the transmit components and one for the receive components). Calibration values for elements of the vectors are computed and maintained in a transmit calibration matrix and a receive calibration matrix, respectively. Together, the transmit calibration matrix and the receive calibration matrix may include fewer elements than a calibration matrix for the virtual channels and, therefore, may require less memory and fewer computations to calibrate a MIMO system than using other calibration techniques. As such, described is a less expensive and less complex way to calibrate MIMO system by accurately approximating an ideal antenna array.