A networked radio frequency identification system includes a plurality of radio frequency identification (RFID) tag readers, a computer in signal communication with the RFID tag readers over a network, and a software module for storage on and operable by the computer that localizes RFID tags based on information received from the RFID tag readers using a network model having endpoints and oriented links. In an additional example, at least one of the RFID tag readers includes an adjustable configuration setting selected from RF signal strength, antenna gain, antenna polarization, and antenna orientation. In a further aspect, the system localizes RFID tags based on hierarchical threshold limit calculations. In an additional aspect, the system controls a locking device associated with an access point based on localization of an authorized RFID tag at the access point and reception of additional authorizing information from an input device.

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.

A radar system for tracking UAVs and other low flying objects utilizing wireless networking equipment is provided. The system is implemented as a distributed low altitude radar system where transmitting antennas are coupled with the wireless networking equipment to radiate signals in a skyward direction. A receiving antenna or array receives signals radiated from the transmitting antenna, and in particular, signals or echoes reflected from the object in the skyward detection region. One or more processing components is electronically coupled with the wireless networking equipment and receiving antenna to receive and manipulate signal information to provide recognition of and track low flying objects and their movement within the coverage region. The system may provide detection of objects throughout a plurality of regions by networking regional nodes, and aggregating the information to detect and track UAVs and other low flying objects as they move within the detection regions.

A pair of radar nodes, each with full azimuthal coverage, cooperate to identify the position of an object without explicit measurements of the object's azimuthal coordinate. A first radar node, operating within a first azimuth field of view (FOV), measures a first elevation angle and a first slant range of the object. A second radar node, operating within a second azimuth FOV, measures a second elevation angle and a second slant range of the object. The second radar node transmits the data to the first radar node, which identifies, based on the first and second azimuth FOVs, an object half space within which the object is located. The first radar node then calculates the position of the object without an ambiguous solution. Alternatively, the first radar uses the first and second azimuth FOVs to identify and reject the ambiguous solution.

A pair of radar nodes, each with full azimuthal coverage, cooperate to identify the position of an object without explicit measurements of the object's azimuthal coordinate. A first radar node, operating within a first azimuth field of view (FOV), measures a first elevation angle and a first slant range of the object. A second radar node, operating within a second azimuth FOV, measures a second elevation angle and a second slant range of the object. The second radar node transmits the data to the first radar node, which identifies, based on the first and second azimuth FOVs, an object half space within which the object is located. The first radar node then calculates the position of the object without an ambiguous solution. Alternatively, the first radar uses the first and second azimuth FOVs to identify and reject the ambiguous solution.

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.

A radar including an interface configured to receive a frequency estimation output and a synchronization signal correlation output from a radio communication device; and a processing block configured to use the received frequency estimation output and synchronization signal correlation output for velocity and range estimation.

A radar including an interface configured to receive a frequency estimation output and a synchronization signal correlation output from a radio communication device; and a processing block configured to use the received frequency estimation output and synchronization signal correlation output for velocity and range estimation.

A method and a system for locating underground targets by using radar signals emitted from a radar transmitter coupled to a transmitter antenna, and echoed signals collected from a target by a radar receiver coupled to a transmitter antenna. The radar signals are collected via the receiver antenna which translates above ground along a closed course in cooperation with the transmitter antenna. The radar signals are processed in correlation with time and with a respective momentaneous location of the receiver antenna and the location of the transmitter antenna. The transmitter antenna is disposed on a land borne platform and the receiver antenna is disposed on the same land borne platform or on another land borne platform or on an airborne platform. The land borne platform and the airborne platform are selected as a mobile platform, a driver guided platform, a remotely guided platform, or an autonomously guided platform.

A system for tracking multiple projectiles includes a first radar device aimed so that a field of view of the first radar device covers at least a portion of a target area into which projectiles are to be launched from a plurality of launch locations and a processor receiving data from the radar and identifying from the data tracks of a plurality of projectiles. The processor determines for each projectile track identified a specific one of the launch locations from which the projectile was launched and provides to the launch location associated with each projectile data corresponding to a trajectory of the projectile.