摘要:
A radar system is proposed. The radar system comprises a radar sensor comprising a first antenna configured to emit a radar beam towards a predefined region. The radar system comprises a reflector spaced apart from the radar sensor and configured to redirect at least part of the radar beam towards a target region different from the predefined region. The radar sensor comprises a second antenna configured to receive a reflection of the radar beam originating from the target region.
摘要:
A system comprises a first sensor on a first end of a vehicle and an on-board controller coupled to the first sensor. The first sensor is configured to detect a radio frequency (RF) signature of a marker along a guideway. The first sensor is a radar detection device. The on-board controller is configured to determine a first position of the vehicle on the guideway or a first distance from the position of the vehicle to a stopping location along the guideway based on at least the RF signature received from the first sensor. The marker is a metasurface plate comprising a first diffused element, a first retroreflector element, a first absorbing element and a second diffused element between the first retroreflector element and the first absorbing element.
摘要:
A multiple-feed antenna system includes a primary reflector that directs signals along a primary RF signal path and a movable subreflector assembly. When the subreflector assembly is in a first position, a first subreflector element of the subreflector assembly redirects signals traveling along the primary RF signal path to a first RF signal path and a second subreflector element of the subreflector assembly does not intersect the primary RF signal path. When the subreflector assembly is in a second position, the second subreflector element redirects signals traveling along the primary RF signal path to a second RF signal path and the first subreflector element does not intersect the primary RF signal path. The antenna system includes a first feed of the antenna system intersects the first RF signal path, a second feed that intersects the second RF signal path, and an actuator that moves the subreflector assembly.
摘要:
A mounting unit (210) securely mounts a radio wave reflection device (200) on a stable installation place such as a pole (20). A reflector unit (300) holds two reflectors (350, 360) at a tilt angle of 45°, allowing the two reflectors (350, 360) to be coaxial and rotatable independently of each other. A joint unit (220) connects the reflector unit (300) and the mounting unit (210). The joint unit (220) has rotational freedom along two axes (AZ axis and EL axis) orthogonal to each other. A radio wave reflecting device that relays, by reflection, radio communications between a first antenna device and a second antenna device distant from each other is thereby provided.