101 results about "Beam tilt" patented technology

A dual polarized variable beam tilt antenna (10) having a plurality of offset element trays (12) each supporting pairs of dipole elements (14) to orient the dipole element pattern boresight at a downtilt. The maximum squint level of the antenna is a consistent downtilt off of boresight and which is at the midpoint of the antenna tilt range. The antenna provides a high roll-off radiation pattern through the use of Yagi dipole elements configured in this arrangement, having a beam front-to-side ratio exceeding 20 dB, a horizontal beam front-to-back ratio exceeding 40 dB, and is operable over an expanded frequency range.

A dual-polarization wireless base station antenna that implements vertical electrical downtilt and sidelobe reduction using beam steering circuit that includes a variable power divider and a multi-beam beam forming network. The variable power divider includes a single adjustable control element to divide an input voltage signal into a pair of complimentary amplitude voltage drive signals that exhibit matched phase and constant phase delay through the variable power divider. The beam forming network is configured as a double-sided, edge-connected microstrip module mounted to a main panel, which support the antenna elements in a vertical column organized into sub-arrays in a manner that implements sidelobe reduction. The power distribution network connecting the beam steering network to the antenna elements implements beam tilt bias and sidelobe reduction through coordinated phase shifting implemented through transmission media trace length adjustment.

An improved communication system and method employing an actively controlled antenna array architecture is disclosed. The array contains a plurality of driven radiating elements that are spatially arranged having a pair of radiating elements fed with an RF signal predistorted so as to provide a controlled variation of the antenna array's elevation radiation pattern. High power amplifier (PA) efficiency is maintained by adaptive predistortion, coupled to each high power PA, while providing beam tilt and side lobe control.

There is provided a phased array antenna having variable phase shifters constituted by using a variable dielectric-constant dielectric substance whose dielectric constant varies according to an applied electric field, which antenna can dispense with a DC blocking element that causes mismatch, and reduce deformation of the beam shape even when beam tilt occurs, in the case where the variable phase shifters are divided into those for right-side tilt and those for left-side tilt and the phase shift amounts thereof are independently controlled.The phased array antenna is provided with a feeding phase shift unit (130) having a laminated structure obtained by laminating at least a ground conductor layer (117), an insulator layer (118), a main conductor layer (119), a variable dielectric-constant dielectric layer (120), and a sub conductor layer (121) in this order, and a propagation characteristic variable line (105) having a line on the sub conductor layer in an area which planarly overlaps a line on the main conductor layer is provided on the feeding phase shift unit. By applying a bias voltage between the main conductor layer and the sub conductor layer, the dielectric constant of the variable dielectric-constant dielectric substance in the propagation characteristic variable line area is varied to control the propagation characteristics. Thereby, a DC blocking element to be inserted in series into the feeding line can be dispensed with.

A dual polarized variable beam tilt antenna (10) having a plurality of offset element trays (12) each supporting pairs of dipole elements (14) to orient the dipole element pattern boresight at a downtilt. The maximum squint level of the antenna is a consistent downtilt off of boresight and which is at the midpoint of the antenna tilt range. The antenna provides a high roll-off radiation pattern through the use of Yagi dipole elements configured in this arrangement, having a beam front-to-side ratio exceeding 20 dB, a horizontal beam front-to-back ratio exceeding 40 dB, and is operable over an expanded frequency range.

A phased array antenna includes a variable phase shifting device configured by using a variable dielectric constant dielectric body whose dielectric constant is varied by an electric field applied. When the variable phase shifting device is divided into a group of right side tilt and a group of left side tilt, phase amounts of which are controlled independently of each other, it is possible to eliminate a DC inhibit element causing mismatch and realize one having a beam shape which is little deformed during beam tilt. The phased array antenna includes a power supply phase shifting unit (130) having at least a ground conducting layer (117), an insulating layer (118), a main conducting layer (119), a variable dielectric constant dielectric layer (120), and a sub constructing layer (121) which are layered in this order. The power supply phase shifting unit has a propagation characteristic variable line (105) having a line on a region of the sub conducting layer superposed on the line on the main conducting layer. By applying a bias voltage between the main conducting layer and the sub conducting layer, it is possible to change the dielectric constant of the variable dielectric constant dielectric body of the propagation characteristic variable line portion so as to control the propagation characteristic. This eliminates the need of a DC inhibit element inserted in series to the power supply line.

A dual polarized three-sector base station antenna with variable beam tilt in each sector. The invention advantageously provides a variable phase shifter with very small lateral dimensions which significantly reduces the diameter of a three-sector antenna. The feed network is located on both sides of the antenna ground plane, and the combination of the cable, microstrip and airstrip lines further reduces the lateral size of the antenna. Metal rings on the radome and double-bended ground plane are providing antenna with better cross-polarization and port-to-port isolation.

A working position measuring system, comprising a rotary laser device for irradiating and rotating a laser beam and a photodetection sensor device for receiving the laser beam and for detecting a working position, wherein the rotary laser device comprises a laser projector for projecting at least two fan-shaped beams with at least one beam tilted, and the photodetection sensor device comprises at least one photodetection unit for receiving the fan-shaped beams and an arithmetic unit for calculating an elevation angle relative to the rotary laser device based on photodetection signals produced when the photodetection unit receives the light beam.

An antenna for radiating an electromagnetic field includes a ground plane, a first dielectric layer disposed on the ground plane, and a second dielectric layer disposed on the first dielectric layer. The antenna includes at least one feeding element embedded in the first dielectric layer and a radiating element extending from the feeding element. The radiating element is embedded within the first dielectric layer adjacent to the second dielectric layer. A beam steering element is embedded in the second dielectric layer and electromagnetically coupled to the radiating element. Embedding the beam steering element in the second dielectric layer and electromagnetically coupling the beam steering element to the radiating element allows the antenna to tilt a radiation beam to overcome a roof obstruction from a vehicle while maintaining acceptable gain, polarization, and directional properties for SDARS applications.

A variable differential phase shifter including an isolation element providing good isolation between output ports, good return loss and reduced reflections. In one embodiment a Wilkinson divider is incorporated in the wiper arm of a wiper type variable differential phase shifter. In another embodiment a linear phase shifter incorporates a Wilkinson divider. Multistage embodiments are also disclosed. The variable differential phase shifter may be used in combination with a hybrid coupler to provide an isolated variable power divider. The variable differential phase shifter may be utilized in a variety of feed networks and antenna arrays to vary beam tilt, beam azimuth and beam width. Antennas incorporating the phase shifter exhibit low variation of half power beam width with frequency and reduced side lobes.

The invention relates to a dual-polarized oblique beam waveguide slot array antenna. The dual-polarized oblique beam waveguide slot array antenna comprises more than one unit array antenna; the unit array antenna is formed by a horizontally polarized linear array and a vertically polarized linear array; the horizontally polarized linear array and the vertically polarized linear array are arranged in a horizontal staggered mode; the horizontally polarized linear array is arranged on the upper layer; the vertically polarized linear array is arranged on the lower layer; a horizontally polarized single ridge waveguide is provided with a broadside V-shaped radiation slot; a vertically polarized single ridge waveguide is provided with a broadside U-shaped radiation slot; a feed portion is in a ridge waveguide form and accordingly the integral bandwidth of the antenna is effectively guaranteed, the antenna achieves beam inclination, meanwhile the matching bandwidth of the antenna and the radiation efficiency are guaranteed. The integral antenna can achieve a good circular polarization axial ratio characteristic and meanwhile achieve a 45-degree fixed beam inclination angle due to appropriate phase compensation of a feed network. Compared with the waveguide slot antenna at the same frequency band, the dual-polarized oblique beam waveguide slot array antenna is small in size, low in profile and effectively reduces costs due to a bolt fastening installation mode.

A vertically polarized traveling wave antenna is omnidirectional, bottom-mounted, and bottom-fed. A robust center coax provides a self-supporting mechanical structure. Multiple dipoles are capacitively coupled to the coax in quads, with a first two dipoles placed on opposite sides of the center coax and spaced by a quarter wavelength along the coax from the second two, which couple at right angles to the first two. This matched-layer spacing cancels the reactive components of the impedances of the dipoles. Beam tilt is readily incorporated over a wide range by adjusting layer spacing to add phase taper. All dipoles are oriented parallel to the coax axis, with opposite “hot” (center coupled) dipole elements oriented oppositely to each other. A radiated signal thus has rotating phase, when viewed from above, but is vertically polarized at each azimuth. A lightweight radome, provided for weather protection, is not needed for structural integrity.

A Multi-Line Phase Shifter (MLPS) for a vertical beam tilt-controlled antenna is provided, in which a housing is shaped into an elongated rectangular box, a fixed plate is attached on an inner bottom surface of the housing and has transmission lines printed thereon, the transmission lines forming part of a plurality of phase shifting patterns and a plurality of signal division patterns, for dividing an input signal and shifting phases of divided signals, and a mobile plate is installed within the housing, movably along a length direction at a position where the mobile plate contacts a surface of the fixed plate, and has transmission lines printed thereon, the transmission lines forming a remaining part of the plurality of phase shifting patterns for phase shifting by forming variable lines through coupling with the part of the plurality of phase shifting patterns.

A charged-particle beam emitting device which includes the following configuration devices so that a lowering in the image resolution will be suppressed even if a primary beam is tilted relative to a sample: A device for causing orbit of the primary beam to pass through off-axes of a plurality of lenses, and controlling off-axis orbit of the primary beam. This device allows the aberration which occurs in the objective lens at the time of beam tilt to be cancelled out by the aberration which occurs in the other lens. Also, there is provided a device for simultaneously modulating excitations of the plurality of lenses including the objective lens.

A tilted illumination observation method and observation device with easy adjustment, high speed, good reproducibility and low cost is provided. A high resolution tilt image of a specimen is obtained by extracting the blurring on the scanning spot occurring during beam tilt from the image (step 6) captured by the tilted beam, and the image (step 4) captured from directly above the standard specimen; and then deconvoluting (step 11, 12) the tilted image of the target specimen (step 10) using the extracted scanning spot from the oblique beam.

A patch antenna receives circularly polarized RF signals from a satellite. The antenna includes a radiating element. A plurality of feed lines feed the radiating element at a plurality of feed points. The feed points are spaced apart to generate a circularly polarized radiation beam solely in a higher order mode at a desired frequency. The antenna may include a plurality of parasitic structures. The feed point spacing and / or the parasitic structures tilt the radiating beam away from an axis perpendicular to the radiating element. Thus, the patch antenna provides excellent RF signal reception from satellites at low elevation angles.

This invention provides a technique for observing defects, which can automatically decide a direction from inclined observation and take an inclined review image. In a defect observing system for detecting the defects and thereafter observing images of the defects from various directions in detail, positions of inclined images to be taken are automatically displayed on a display screen from a planar image (top-down image) of a SEM using CAD data, and the defects are selected from the images displayed on the display screen based on specification by a user, an inclined angle and direction are determined per selected image to take an inclined image (beam-tilt image), and the inclined image of each defect is acquired.

A test fixture for characterizing a device-under-test (DUT) includes first and second planar antennas and a planar waveguide arranged to guide terahertz (THz) and / or millimeter wave (mmW) radiation between the first and second planar antennas. The planar waveguide is further configured to couple THz and / or mmW radiation guided between the first and second planar antennas with the DUT. A beam forming apparatus is arranged to transmit a probe THz and / or mmW radiation beam to the first planar antenna of the test fixture. An electronic analyzer is configured to wirelessly receive a THz and / or mmW signal emitted by the second planar antenna responsive to transmission of the probe THz and / or mmW radiation beam to the first planar antenna. The planar antennas may be asymmetrical beam-tilted slot antennas.

A circularly polarized, omnidirectional, corporate-feed pylon antenna uses multiple helically-oriented dipoles in each bay, and includes a vertical and diagonal support arrangement of simple structural shapes configured to provide a frame strong enough to sustain mechanical top loads applied externally. The radiators in each bay fit within the vertical supports. The radiators are integrally formed with cross-braces, and are fed with manifold feed straps incorporating tuning paddles. A single cylindrical radome surrounds the radiative parts and the vertical supports. The antenna admits of application to the upper L-band at the full FCC-allowed ERP. Beam tilt, null fill, and vertical null can be readily accommodated.

The LTCC (Low Temperature Co-fired Ceramic) substrate is used to form an antenna structure operating at 60 GHz. The dielectric constant is high and ranges from 5 to 8. The substrate thickness is fabricated with a thickness between 360 μm to 700 μm. The large dielectric constant and large thickness of the substrate creates a guiding wave in the LTCC that forms an endfire antenna. A high gain signal of 10 dB in a preferred direction occurs by placing the microstrip fed dipole structure in the center of the LTCC substrate creating a dielectric cavity resonator. The creation of a slot in the LTCC substrate between the two microstrip fed dipole structures eliminates beam tilting and allows for the two microstrip fed dipole structures to reduce the coupling to each other thereby providing substantially two isolated endfire antennas. These antennas can be used as multiple receive or transmit antennas.

An improved communication system and method employing an actively controlled antenna array architecture is disclosed. The array contains a plurality of driven radiating elements that are spatially arranged having a pair of radiating elements fed with an RF signal predistorted so as to provide a controlled variation of the antenna array's elevation radiation pattern. High power amplifier (PA) efficiency is maintained by adaptive predistortion, coupled to each high power PA, while providing beam tilt and side lobe control.

A short wave omnidirectional antenna for the 26 Megahertz band provides line-of-sight broadcasting at comparatively low power to serve local communities while suppressing sky wave propagation. Sky wave suppression is achieved by a critically configured reflector above the radiator or by a co-located second active or parasitic radiator spaced to achieve sufficient beam tilt to create a null at critical angles, generally from the horizon to thirty degrees above. This arrangement allows local broadcasts to be originated at numerous sites despite the narrow extent of the band (330 kHz) and the narrow (10 kHz) channel width. Among other possible applications, the antenna supports transmission using the Digital Radio Mondiale® (DRM®) system for COFDM. COFDM technology can suppress ghosting and most noise, while low emission angle of the antenna and low intended transmitter power largely prevent interference between broadcasts at moderate distances.

A variable differential phase shifter including an isolation element providing good isolation between output ports, good return loss and reduced reflections. In one embodiment a Wilkinson divider is incorporated in the wiper arm of a wiper type variable differential phase shifter. In another embodiment a linear phase shifter incorporates a Wilkinson divider. Multistage embodiments are also disclosed. The variable differential phase shifter may be used in combination with a hybrid coupler to provide an isolated variable power divider. The variable differential phase shifter may be utilized in a variety of feed networks and antenna arrays to vary beam tilt, beam azimuth and beam width. Antennas incorporating the phase shifter exhibit low variation of half power beam width with frequency and reduced side lobes.