A radar apparatus includes a transmission-reception antenna unit including a plurality of transmission antennas and a plurality of reception antennas along a predetermined array direction, which form a virtual array in which a plurality of virtual reception antennas are arranged along the array direction. Based on virtual reception signals received by the virtual reception antennas, the radar apparatus detects an object that reflects transmission signals, calculates a transmission phase difference between the transmission antennas of the transmission signals transmitted by the transmission antennas, and calculates a reception phase difference between the reception antennas of reception signals received by the reception antennas. The radar apparatus calculates a transmission-reception phase difference that is a difference between the calculated transmission phase difference and the calculated reception phase difference, and determines that the detected object is a ghost, in response to the calculated transmission-reception phase difference being greater than a predetermined phase threshold.

Devices and systems for implementing a walk-through gate are provided. The devices include a walk-through gate structure having boundaries that have curved inner surfaces on each side of a cavity. The curved inner surfaces are partially covered by a reflective material. The devices include radio frequency (RF) signal transmitters positioned tangent to the curved inner surfaces and RF signal receivers. The devices also include apertures that provide access to the cavity of the walk-through gate structure.

A method for supporting radar operations may involve providing, from a radar server, one or more transmit beam parameters, over one or more wired or wireless interfaces, to a first wireless communications system Transmission Reception Point (TRP) for configuring a transmit beam for sending a transmit signal from the first wireless communications TRP. The method may further involve providing, from the radar server, one or more receive beam parameters, over one or more wired or wireless interfaces, to a second wireless communications system TRP for configuring a receive beam for receiving, at the second wireless communications system TRP, an echo signal from one or more targets as a reflection of the transmit signal. The first wireless communications system TRP and the second wireless communications system TRP may be part of a wireless communications system.

A system and method of tracking a hypersonic object over a flightpath includes at least one observer having at least one sensor. The sensor is configured to provide measurements of the hypersonic object that are geometrically diverse such that each observer may independently measure any combination of range, angles, Doppler, and angle rates. The observers transmit measurements to a processing unit as the hypersonic object undergoes three phases including a boost phase, a ballistic phase, and a hypersonic glide phase. The hypersonic object is tracked over many time steps by first selecting a dynamics model representative of expected object kinematics during said phase. Then, an unscented Kalman filter is used to predict a future state and a covariance using the dynamics model that was selected. Finally, the unscented Kalman filter updates the future state and covariance that were predicted based on the geometrically diverse measurements of the sensors.

An electronic device may include a plurality of antennas, a memory storing at least one reference data, and a processor. The processor may be configured to obtain context information associated with a state of the electronic device, when the context information meets a first specified condition, determine phase difference information corresponding to signals obtained using the plurality of antennas based on first specified reference data, when the context information meets a second specified condition, determine phase difference information corresponding to signals obtained using the plurality of antennas based on second specified reference data, and determine a relative location of an external electronic device with respect to the electronic device based on the determined phase difference information.

An electronic device may include a plurality of antennas, a memory storing at least one reference data, and a processor. The processor may be configured to obtain context information associated with a state of the electronic device, when the context information meets a first specified condition, determine phase difference information corresponding to signals obtained using the plurality of antennas based on first specified reference data, when the context information meets a second specified condition, determine phase difference information corresponding to signals obtained using the plurality of antennas based on second specified reference data, and determine a relative location of an external electronic device with respect to the electronic device based on the determined phase difference information.

An example display system includes: a display; an input device configured to transmit an initial position signal; a plurality of antenna modules configured to transmit a position detection signal, receive a reflection signal of the position detection signal that is reflected from the input device and a surrounding object, and receive the initial position signal transmitted from the input device; and a controller configured to perform control to cause a pointer to be displayed on the display based on a position of the input device according to the received initial position signal and the reflection signal.

An example display system includes: a display; an input device configured to transmit an initial position signal; a plurality of antenna modules configured to transmit a position detection signal, receive a reflection signal of the position detection signal that is reflected from the input device and a surrounding object, and receive the initial position signal transmitted from the input device; and a controller configured to perform control to cause a pointer to be displayed on the display based on a position of the input device according to the received initial position signal and the reflection signal.

According to one embodiment, a radar apparatus includes first antennas, a second antenna, and a third antenna. If the first antennas are used as transmission antennas, the second and third antennas are used as reception antennas. If the second and third antennas are used as the transmission antennas, the first antennas are used as the reception antennas. The first antennas are arranged in a first direction at a first distance and in a second direction crossing the first direction at a second distance. A distance between the second antenna and the third antenna in the first direction is approximately equal to a product of the first distance and a number of first antennas arranged in the first direction.

According to one embodiment, a radar apparatus includes first antennas, a second antenna, and a third antenna. If the first antennas are used as transmission antennas, the second and third antennas are used as reception antennas. If the second and third antennas are used as the transmission antennas, the first antennas are used as the reception antennas. The first antennas are arranged in a first direction at a first distance and in a second direction crossing the first direction at a second distance. A distance between the second antenna and the third antenna in the first direction is approximately equal to a product of the first distance and a number of first antennas arranged in the first direction.