261 results about "Beam tracking" patented technology

A method and an apparatus for tracking an uplink beam in a beamforming-based cellular system are disclosed. A method for a terminal comprises the steps of: transmitting, to a serving base station, a measurement report containing signal qualities of the serving base station and neighboring base stations; receiving, from the serving base station, uplink beam tracking information of at least one beam tracking target base station; transmitting an uplink beam training signal for the beam tracking target base station, on the basis of the uplink beam tracking information; and receiving, from the serving base station, information on an optimum terminal transmission beam of the beam tracking target base station, and storing the received information.

Disclosed is a novel scanning-probe type atomic force microscope wherein false deflection of the probe is reduced. The probe of the scanning-probe type atomic force microscope moves in both the horizontal direction and the vertical direction during the scanning, while the sample is kept in order to reduce the false deflection brought to the probe due to the scanning motion, two approaches are adopted. The first is to have a focused laser spot tracking an invariant point on the probe's cantilever, which moves three-dimensionally during the scanning. The second approach is to have the laser beam, which is reflected from the moving cantilever, hitting an invariant point of the PSD, when the sample is distanced from the probe and induces no deflection. A beam tracking system wherein the scanning probe is located approximately at the focal point of an objective lens and he optical system including a laser source, an optical module, a feedback module and the probe are driven by an approach mechanism to move in synchronization.

The present invention relates to a vehicle mountable satellite antenna as defined in the claims which is operable while the vehicle is in motion. The satellite antenna of the present invention can be installed on top of (or embedded into) the roof of a vehicle. The antenna is capable of providing high gain and a narrow antenna beam for aiming at a satellite direction and enabling broadband communication to vehicle. The present invention provides a vehicle mounted satellite antenna which has low axial ratio, high efficiency and has low grating lobes gain. The vehicle mounted satellite antenna of the present invention provides two simultaneous polarization states. In one embodiment, a hybrid mechanic and electronic steering approach provides a more reasonable cost and performance trade-off. The antenna aiming in the elevation direction is achieved via control of an electronic beamforming network. The antenna is mounted on a rotatable platform under mechanical steering and motion control for aiming the antenna in the azimuth direction. Such approach significantly reduces the complexity and increases the reliability of the mechanical design. The antenna height is compatible to the two-dimensional electronic steering phased-array antenna. Additionally, the number of the electronic processing elements required is considerably reduced from that of the conventional two-dimensional electronic steering phased-array antenna, thereby allowing for low cost and large volume commercial production. The present invention provides electronically generated left, right, up, and down beams for focusing the antenna beam toward the satellite while the vehicle is moving. All of the beams are simultaneously available for use in the motion beam tracking. This provides much faster response and less signal degradation.

An antenna-receiver communications system and method is provided to mechanize multibeam mobile antenna-receive subsystems. Digital beam forming for modern wideband mobile communications systems is provided. In an aspect, subsystems can simultaneously receive, acquire, track and output a multiplicity of signals from sources of different locations using a single antenna aperture from a mobile platform. The angle of arrival of a signal of interest is continuously determined. Individual phased array antenna output channels are phased aligned as required by the phased array equation and monopulse signal processing. Angle sensing and beamsteering are separated from antenna channel coherent summation. Thus, the angle sensing and beamsteering functions are not required to be computed at the data rate, but can instead be computed at a rate necessary for the beam acquisition and beam tracking function speed requirements. Signal processing computational load and system cost is reduced as compared to current systems.

An iono-refractive structure that includes one or more ion insertion layers having a real portion and an imaginary portion of the dielectric constant is provided. While both the real portion and the imaginary portion of the dielectric constant change, the change in the imaginary portion is less than the change in the real portion at the wavelength of interest or at the operational wavelength. The iono-refractive structure may be suitable for the fabrication of or integration with tunable optical filters, wavelength-selective optical elements, active modulated interferometers, optical phase shifters, optical phased array beam steering, optical phased array beam tracking, tunable optical filters, sensors, variable lenses, tunable diffraction gratings, and other optical components.