Showing papers on "Reflector (antenna) published in 2003"

LED lamp heat sink

Abstract: An LED lamp includes an exterior shell that has the same form factor as a conventional incandescent light bulb, such as a PAR type bulb. The LED lamp includes an optical reflector that is disposed within the shell and that directs the light emitted from one or more LEDs. The optical reflector and shell define a space that is used to channel air to cool the device. The LED is mounted on a heat sink that is disposed within the shell. A fan moves air over the heat sink and through the spaced defined by the optical reflector and the shell. The shell includes one or more apertures that serve as air inlet or exhaust apertures. One or more apertures defined by the optical reflector and shell at the opening of the shell can also be used as air exhaust or inlet apertures.

Planar artificial magnetic conductors and patch antennas

Abstract: Surfaces act as perfect magnetic conductors (PMC) if the phase shift of the reflection of an electromagnetic wave amounts to 180/spl deg/ compared to the reflection at a perfect electric conductor (PEC). One possibility to create PMC surfaces artificially is an array of closely spaced patches. In this paper, based on the relation between PMC surfaces and patch antennas, an explanation for the functioning of this artificial PMC is given. An equivalent network is derived that allows to understand the functioning and to provide a starting design for a numerical optimization by aid of fullwave methods. A planar PMC is used for the first time as a reflector for a large aperture coupled patch antenna array, especially in order to reduce the parallel-plate modes that are usually present in traditional aperture coupled patch arrays. An additional sidelobe suppression of over 6 dB has been achieved by the planar PMC reflector in comparison to a traditional reflector.

Self-packaged optical interference display device having anti-stiction bumps, integral micro-lens, and reflection-absorbing layers

Abstract: An electronic device of an embodiment of the invention is disclosed that at least partially displays a pixel of a display image. The device includes a first reflector and a second reflector defining an optical cavity therebetween that is selective of a visible wavelength at an intensity. The device includes a mechanism to allow optical properties of the cavity to be varied such that the visible wavelength and/or the intensity are variably selectable in correspondence with the pixel of the displayable image. The device also includes one or more transparent deposited films, one or more absorbing layers, an integral micro-lens, and/or one or more anti-stiction bumps. The deposited films are over one of the reflectors, for self-packaging of the device. The absorbing layers are over one of the reflectors, to reduce undesired reflections. The integral micro-lens is over one of the reflectors, and the anti-stiction bumps are between the reflectors.

Optical interference pixel display with charge control

Abstract: An electronic device of an embodiment of the invention is for at least partially displaying a pixel of a displayable image. The electronic device includes a first reflector and a second reflector that define an optical cavity therebetween, and which is selective of a visible wavelength at an intensity by optical interference. The electronic device also includes a charge-controlling mechanism to allow optical properties of the optical cavity to be varied by controlling a predetermined amount of charge stored on the first and the second reflectors. The visible wavelength and/or the intensity are thus variably selectable in correspondence with the pixel of the displayable image.

Concentrating solar energy receiver

Abstract: There is disclosed herein a concentrating solar energy receiver comprising a primary parabolic reflector having a center and a high reflectivity surface on a concave side of the reflector and having a focal axis extending from the concave side of the reflector and passing through a focal point of the primary parabolic reflector, and a conversion module having a reception surface wherein the reception surface is spaced from the focal point by a predetermined distance and disposed to receive a predetermined cross section of radiant solar energy reflected from the concave side of the primary parabolic reflector for conversion to electrical energy in the conversion module. In one aspect, the conversion module includes a reception surface comprising a planar array of at least one photovoltaic solar cell. In another aspect, the conversion module includes a reception surface coupled to a thermal cycle engine. The mechanical output of the thermal cycle engine drives an electric generator.

Antenna having at least one dipole or an antenna element arrangement similar to a dipole

Abstract: An improved antenna includes a coupling element in the form of a rod. The coupling element is electrically conductive and extends transversely with respect to the reflector plane is provided on the front face of the reflector. A mount device has an axial hole in the interior. The axial hole in the mount device can be placed on the coupling element which is in the form of a rod, such that the mount device and the coupling element which is the form of a rod are capacitively coupled, while avoiding any electrically conductive contact.

Light-emitting device and manufacturing method thereof

Abstract: In the light-emitting device provided with the conventional wavelength converter, colors became irregular, and light radiated to a side of the semiconductor light-emitting element from the wavelength converter could not be used as radiation light, thus lowered the conversion efficiency. The present invention improves the availability of the light from the wavelength converter 5 and resolves the problems by realizing a composition of an LED lamp, wherein a light-radiation-direction-limiter 4 a and reflector 4 b around it are mounted on a substrate 4, a wavelength converter 5 is mounted on a proper position to cover a part of the light-radiation-direction-limiter 4 a and the reflector 4 b , and among the light whose wavelength gets converted from fundamental wavelength-light into wavelength-converted light at the wavelength converter 5, both the wavelength-converted light transmitted through the aforementioned wavelength converter 5 and radiated to the front face as direct light, and the wavelength-converted light radiated to the inner face of the wavelength converter 5, by reflecting towards the radiation direction of this light-emitting 1 by the reflector 4 b , can be taken out as output light.

Methods of making phosphor based light sources having an interference reflector

Abstract: A method of manufacturing a light source includes the steps of providing a first flexible sheet comprising a first multilayer interference reflector, providing a carrier film to carry the reflector, dividing the reflector into individual pieces carried by the carrier film, and positioning at least one of the individual pieces proximate an LED capable of emitting light that excites a phosphor material.

Parametric design and analysis of multiple-beam reflector antennas for satellite communications

Abstract: This paper presents the parametric design and analysis of multiple-beam reflector-antenna systems employed for satellite communications. It is based on extending the earlier work of Rao (see IEEE Antennas and Propagation Magazine, vol.41, no.4, p.53-59,1999) by taking into account the efficiency of the horn and pointing error of the satellite in the design of the multiple-beam antennas (MBAs), and by analyzing the edge-of-coverage directivity and co-polar isolation (C/I) performance. Design and analysis equations are developed for the multiple-beam antennas using offset parabolic-reflector antennas by including various design parameters such as the number of reflectors, the number of frequency cells, the focal-length-to-diameter (F/D) ratio, the horn efficiency, and the pointing error. The analysis employs a quasi-Gaussian beam representation for the primary and secondary patterns in order to take into account the effect of the sidelobes. Results of the analysis given in this paper agree well with rigorous computations based on physical optics analysis of the antenna radiation. Design curves showing the impact of horn efficiency on the C/I performance of multiple-beam antennas are presented for various frequency-reuse schemes.

Semiconductor light emitting device, method for producing the same and reflector for semiconductor light emitting device

Abstract: A semiconductor light emitting device comprising a metallic supporting plate (1), an optical reflector (3) bonded to the supporting plate (1), a light emitting diode (2) bonded onto the supporting plate (1) in the inner cavity (3a) of the reflector (3), and a resin sealing body (6) sealing the outer circumferential part of the reflector (3) and the upper surface (1c) of the supporting plate (1). Since the reflector (3) is connected electrically with a wiring body (5) or the semiconductor light emitting diode (2) is connected with the wiring body (5) by means of fine lead wires (8) passing through a cut (3k) made between the light emitting diode (2) and the wiring body (5), the fine lead wires (8) connected with the semiconductor light emitting element can be protected against deformation by shortening the wiring distance of the fine lead wires (8), and optical directivity and front luminance of the semiconductor light emitting element can be enhanced by decreasing the diameter of the reflective surface (3c) of the reflector (3) and increasing the height from the supporting plate (1). Furthermore, thermal deterioration of resin can be avoided by forming the resin sealing body (6) of heat resistant resin because the inner cavity (3a) can be formed in the reflector (3).

Apparatus and method for operating a portable xenon arc searchlight

Abstract: A xenon arc searchlight or illumination system incorporates a high frequency/high efficiency electronic circuit that allows lamp ballasting and charging of the system battery to occur over a wide range of external DC power supplies. The tolerance to variations in the system battery voltage as well as external battery voltage are increased by providing logic control of the converter circuit through a programmed logic device. The intensity of the arc lamp is smoothly decreased or increased in a continuous manner from a maximum intensity to a minimum intensity beam. Ignition of the lamp at its minimum illumination levels is thereby permitted. The xenon arc lamp is uniquely oriented within the searchlight with respect to the reflector to provide the most concentrated and convergent field of illumination on which the lamp is capable, namely with the anode of the lamp turned away from the forward beam direction in the reflector. The resulting light beam is focused by relative movement of a reflector with respect to the lamp by advancing or retracting the reflector along its optical axis of symmetry on which the lamp is also aligned. The searchlight is designed so that the lamp, reflector and battery assemblies are easily field replaceable without tools. The lamp, ballast, battery and charger are provided in a single rugged package which can be sealed for field use. The searchlight is combined by an appropriate mounting adaptable with other optical detector devices such as cameras, binoculars and night vision telescopes. The beam output is similarly usable with a combination of filters to allow the most varied intensity and wavelengths for a particular application, such as smoke filled environments, surveillance employing near-infrared or infrared illumination, ultraviolet, underwater illumination or illumination with any color in the visible range.

Sign illumination system

Abstract: A radiation-emitting device comprising a side-emitting optoelectronic device having an upper surface and a heat sink in thermal conductivity with the side-emitting optoelectronic device. A reflector at least partially surrounds the side-emitting optoelectronic device. The reflector is positioned and shaped to reflect the emitted light substantially in an output direction. A reflective, non-transparent layer is disposed adjacent the upper surface of the side-emitting optoelectronic device.

Titanium-containing interference pigments and foils with color shifting properties

Abstract: Interference pigment flakes and foils are provided which have color shifting properties. The pigment flakes can have a symmetrical coating structure on opposing sides of a reflector layer, can have an asymmetrical coating structure with all of the layers on one side of the reflector layer, or can be formed with encapsulating coatings around a core reflector layer. The coating structure of the flakes and foils includes a reflector layer, a dielectric layer on the reflector layer, and a titanium-containing absorber layer on the dielectric layer. The pigment flakes and foils exhibit a discrete color shift so as to have a first color at a first angle of incident light or viewing and a second color different from the first color at a second angle of incident light or viewing. The pigment flakes can be interspersed into liquid media such as paints or inks to produce colorant compositions for subsequent application to objects or papers. The foils can be laminated to various objects or can be formed on a carrier substrate.

Light-emitting diode reflector assembly having a heat pipe

Abstract: A light-emitting diode reflector assembly having a heat pipe and a reflector body is provided. The assembly further includes a mounting member for mounting a circuit board having an array of light-emitting diodes. The mounting member and reflector body are made from a thermally-conductive polymer composition comprising: i) about 20% to about 80% by weight of a base polymer matrix such as polycarbonate; and ii) about 20% to about 80% by weight of a thermally-conductive material such as carbon graphite.

Lithographic Apparatus, and Device Manufacturing Method

Abstract: PURPOSE: A lithographic apparatus and a device manufacturing method are provided to be capable of detecting position error and disturbances of a reflector by real-time CONSTITUTION: A reflector alignment system(10) uses an alignment beam(AB1) propagating through a projection system(PL) comprising a mirror group to measure the apparent relative positions of two reference markers fixed to a reference frame(RF) on opposite sides of the projection system The movement of mirrors in the projection system(PL) detects as a shift in the apparent position of a plurality reference markers(11,14)

Large antennas of the Deep Space Network

Abstract: Foreword.Preface.Acknowledgments.Chapter 1 : Introduction.1.1 Technology Drivers.1.1.1 Frequency Bands Allocated to the Deep Space Network.1.2 Analysis Techniques for Designing Reflector Antennas.1.2.1 Radiation-Pattern Analysis.1.2.2 Feed-Horn Analysis.1.2.3 Spherical-Wave Analysis.1.2.4 Dual-Reflector Shaping.1.2.5 Quasioptical Techniques.1.2.6 Dichroic Analysis.1.2.7 Antenna Noise-Temperature Determination.1.3 Measurement Techniques.1.3.1 Theodolite Measurements.1.3.2 Microwave Holography.1.3.3 Aperture Gain and Efficiency Measurements.1.3.4 Noise-Temperature Measurements.1.4 Techniques for Designing Beam-Waveguide Systems.1.4.1 Highpass Design.1.4.2 Focal-Plane Matching.1.4.3 Gaussian-Beam Design.1.4.4 High-Power Design.1.5 Summary.References.Chapter 2: Deep Space Station 11: Pioneer-The First Large Deep Space Network Cassegrain Antenna.2.1 Introduction to the Cassegrain Concept.2.2 Factors Influencing Cassegrain Geometry.2.3 The DSS-11, 26-Meter Cassegrain System.References.Chapter 3: Deep Space Station 12: Echo.3.1 The S-Band Cassegrain Monopulse Feed Horn.3.2 The 26-Meter S-/X-Band Conversion Project.3.2.1 Performance Predictions.3.2.2 Performance Measurements.3.3 The Goldstone-Apple Valley Radio Telescope.References.Chapter 4: Deep Space Station 13: Venus.4.1 The Dual-Mode Conical Feed Horn.4.2 Gain Calibration.References.Chapter 5: Deep Space Station 14: Mars.5.1 Antenna Structure.5.2 S.Band. 1966.5.3 Performance at X-Band.5.3.1 Surface Tolerance.5.3.2 Measured X-Band Performance.5.4 Tricone Multiple Cassegrain Feed System.5.4.1 Radio Frequency Performance.5.4.2 New Wideband Feed Horns.5.4.3 Dual-Hybrid-Mode Feed Horn.5.5 Reflex-Dichroic Feed System.5.6 L-Band.5.6.1 Design Approach.5.6.2 Performance Predictions and Measurements.5.6.3 L-Band System Modifications.5.7 The Upgrade from 64 Meters to 70 Meters.5.7.1 Design and Performance Predictions.5.7.2 S- and X-Band Performance.5.7.3 Ka-Band Performance.5.7.4 Adding X-Band Uplink.5.8 Distortion Compensation.5.8.1 Deformable Flat Plate.5.8.2 Array-Feed Compensation System.5.8.3 The Array-Feed Compensation System-Deformable Flat-Plate Experiment.5.8.4 Projected Ka-Band Performance.5.9 Future Interests and Challenges.References.Chapter 6: Deep Space Station 15: Uranus-The First 34-Meter High-Efficiency Antenna.6.1 The Common-Aperture Feed.6.2 Dual-Reflector Shaping.6.3 Computed versus Measured Performance.References.Chapter 7: The 34-Meter Research and Development Beam-Waveguide Antenna.7.1 New Analytical Techniques.7.2 Beam-Waveguide Test Facility.7.3 The New Antenna.7.3.1 Antenna Design Considerations.7.3.2 Upper-Mirror Optics Design.7.3.3 Pedestal Room Optics Design.7.3.4 Bypass Beam-Waveguide Design.7.3.5 Theoretical Performance.7.3.6 Dual-Shaped Reflector Design.7.3.7 The Effect of Using the DSS-I 5 Main Reflector Panel Molds for Fabricating DSS-13 Panels.7.4 Phase I Measured Results.7.4.1 The X- and Ka-Band Test Packages.7.4.2 Noise Temperature.7.4.3 Efficiency Calibration at 8.45 and 32 GHz.7.4.4 Optimizing the G/T Ratio of the Beam- Waveguide Antenna.7.4.5 Beam-Waveguide Antenna Performance in the Bypass Mode.7.5 Removal of the Bypass Beam Waveguide.7.6 Multifrequency Operation.7.6.1 X-IKa-Band System.7.6.2 S-Band Design.7.7 Bearn-Waveguide Versatility.References.Chapter 8: The 34-Meter Beam-Waveguide Operational Antennas.8.1 Bearn-Waveguide Design.8.2 Initial Testing.8.2.1 Microwave Holography Measurements.8.2.2 Efficiency Measurements.8.2.3 Noise-Temperature Results.8.2.4 Theshroud.8.3 Adding Ka-Band to the Operational 34-Meter Bearn-Waveguide Antennas.8.3.1 The Cassini Radio Science Ka-Band Ground System.8.3.2 Ka-Band Upgrades-Receive-Only System.References.Chapter 9: The Antenna Research System Task.9.1 Design of the Beam-Waveguide System.9.2 Design of the Transmit Feed Horn.9.3 Receive-System Design.9.4 Dual-Vane Polarizers.9.5 Uplink Arraying.9.6 Deep Space Station 27.References.Chapter 10: The Next-Generation Deep Space Network.10.1 The Study to Replace 70-Meter Antennas.10.1 . 1 Extending the Life of the Existing 70-Meter Antennas.10.1.2 Designing a New 70-Meter Single-Aperture Antenna.10.1.3 Arraying Four 34-Meter Aperture Antennas.10.1. 4 Arraying Small Antennas.10.1.5 Arraying Flat-Plate Antennas.10.1.6 Implementing a Spherical Pair of High-Efficiency Reflecting Elements Antenna Concept.10.2 Towards the Interplanetary Network.10.3 Final Thoughts.References.Acronyms and Abbreviations.

High-intensity directional light

Abstract: A high-intensity light comprising a side-emitting optoelectronic device adapted to emit light of a desired color. A heat sink is positioned adjacent the optoelectronic device and a reflector at least partially surrounds the optoelectronic device. The reflector is spaced a distance from the optoelectronic device. A window portion is sized to output the light in a desired arc.

Acoustic reflector for a BAW resonator providing specified reflection of both shear waves and longitudinal waves

Abstract: A BAW resonator includes a piezoelectric layer, a first electrode, a second electrode, a substrate, and an acoustic reflector disposed between the substrate and the second electrode The acoustic reflector has a plurality of layers A performance of the acoustic reflector is determined by its reflectivity for a longitudinal wave existing in the BAW resonator at the resonance frequency of the BAW resonator and by its reflectivity for a shear wave existing in the BAW resonator at the resonance frequency of the BAW resonator The layers of the acoustic reflector and layers disposed between the acoustic reflector and the piezoelectric layer are selected, with reference to their number, material, and thickness, such that the transmissivity for the longitudinal wave and the transmissivity for the shear wave in the area of the resonance frequency is smaller than −10 dB

Forward-looking radar system

Abstract: An assembly for receiving and transmitting millimeter (mm) waves, including at least one mm wave reflector (84, 86, 88)and at least one mm transmission wave feed (72) configured in a transmission feed location (34) within the at least one mm wave reflector. The assembly also includes a plurality of receiving mm wave feeds (72) configured in respective receiving feed locations (36) within the at least one mm wave reflector; and a radio frequency (RF) module (38). The RF module is coupled to the at least one mm transmission wave feed and to the plurality of the receiving mm wave feeds, so as to drive the at least one mm transmission wave feed to transmit outgoing mm waves and to simultaneously receive incoming mm waves from all of the plurality of the receiving mm wave feeds.

Electronically steerable parasitic array radiator antenna for omni- and sector pattern forming applications to wireless ad hoc networks

Abstract: An electronically steerable parasitic array radiator antenna is presented. The antenna has only a single element connected to a receiver or a transmitter. This active element is surrounded by parasitic elements loaded with variable reactors (varactors). The loaded reactance and the length of the parasitic radiators are designed so that each of the parasitic elements plays its role of director or reflector depending on its bias voltage on the loaded reactance. This design guarantees that the radiation pattern can be controlled by changing the bias voltages on the varactors. For omnipattern forming, a voltage vector is obtained such that the received power is maximised under the assumption that each component of the voltage vector is equal. An experiment yields an omnipattern with an average −0.83 dBi gain over the angles [0°, 360°). For sector pattern forming, a single-source power maximisation technique is proposed to optimise the voltage vector such that the received signal power is as large as possible in the direction of the source. Experiments yield twelve sector patterns at every 30°. The average gain is 5.5 dBi in the patterns' beam directions. The average 3 dB beamwidth is 72.4° for the sector patterns in the directions 0°, 60°, 120°, 180°, 240°, and 300°, while the average value is 90.1° for the remaining patterns.

GaAs-based near-infrared omnidirectional reflector

Abstract: We introduce a compound-semiconductor-based omnidirectional reflector. A four-layer-pair stack of GaAs/AlAs was grown epitaxially using molecular-beam epitaxy, and was then converted to a GaAs/Al2O3 multilayer stack by selective oxidation of the AlAs layers. The resultant one-dimensional photonic crystal exhibited omnidirectional reflection properties in near-IR wavelength range below 1 μm. Reflectance spectra measured at various incidence angles and polarizations were observed to be in good agreement with theoretically simulated results.

Small reflector antenna with low sidelobes

Abstract: A prime focus low sidelobe parabolic reflector antenna with self-supported feed is designed for low sidelobe applications. The parabolic reflector diameter is between nine and twelve wavelengths. A simple design is achieved to satisfy the required first sidelobe level. The design is performed numerically using a computer code for bodies of revolutions (AKBOR2). The measured radiation patterns of 18 inch and 24 inch reflector systems at 5.75 GHz. are presented. Good agreement between computed and measured radiation patterns is obtained.

Reflector providing particularly high reflectance in an intended viewing angle and reflection type liquid crystal display device using the same

Abstract: The present invention provides a reflector having a light-diffusing property which suppresses inter-object reflection over a wide angle, and giving particularly high reflectance in an intended range of viewing angle; and to provide a reflection type liquid crystal display device using the same. The reflector includes a plurality of light-reflective concave portions. Each of the concave portions is formed so that an inclination angle (an angle between a plane tangential to a point on a concave surface and the surface of the base material) is maximum on a side portion of the curved surface, and so that the direction of the side portion having the maximum inclination angle is on a far side from a view point of an observer. Moreover, the reflector includes many concave portions formed on a reflector surface, an inner surface of each of the concave portions including a peripheral curved surface and a bottom curved surface that are continuously connected to each other, the peripheral curved surface being a part of a first sphere having a first radius, the bottom curved surface being a part of a second sphere having a second radius different from the first radius, and the bottom curved surface being located within the peripheral curved surface, wherein the first radius is smaller than the second radius, and a normal line extending from a center of the first sphere to the reflector surface and a normal line extending from a center of the second sphere to the reflector surface are not collinear. Further, the reflection type liquid crystal display device is provided with the reflector.

Compact micro-concentrator for photovoltaic cells

Abstract: A reflector array comprises a plurality of partial parabolic reflectors arranged in rows and columns with each reflector directing radiation to a receiver or from a transmitter located at the focus of the reflector. In a compact photovoltaic cell arrangement, each cell is shielded from direct radiation by the adjacent reflector. The reflectors can be formed as one unit with reflective material or with the reflecting surfaces coated with aluminum, silver, or other suitable reflecting material. A secondary reflector can be positioned at the focus of a reflector for directing radiation to a receiver or from a transmitter located at a more accessible location in the array.

Lithographic apparatus, device manufacturing method and device manufactured thereby, control system

Abstract: A lithographic projection system has an illumination system. A plurality of directing elements direct different sub-beams of an incident beam into predetermined directions. By using re-directing optics any desired angular intensity distribution of the projection beam can be produced. The illumination system includes a setting device that includes a reflector plate that supports reflectors. The reflectors are resiliently supported on the reflector plate. At least one aperture in the reflector plate is associated with each reflector. A setting plate includes at least one pin associated with each reflector. The pins of the setting plate are insertable into the apertures of the reflector plate. Each pin or pins engages its associated reflector to control the orientation of the associated reflector by rotation about two axes substantially perpendicular to the optical axis of the associated reflector.

Lithographic projection apparatus and reflector assembly for use therein

Abstract: A lithographic projection apparatus includes a grazing incidence collector. The grazing incidence collector is made up of several reflectors. In order to reduce the amount of heat on the collector, the reflectors are coated. The reflector at the exterior of the collector has an infrared radiating layer on the outside. The inner reflectors are coated with an EUV reflective layer on the outside.

Radio communication system

Abstract: PROBLEM TO BE SOLVED: To provide a radio communication system by which scattering of signals can be prevented and the signals can be effectively used SOLUTION: The RFID system 1 has an interrogator 11, an interrogator antenna 12 which is connected with the interrogator 11 and transmits signals, an approximately elliptic radio wave reflector 14 which reflects the signals emitted from the interrogator antenna 12 and radio tags 13 which receive the signals from the interrogator antenna 12 through at least the approximately elliptic radio wave reflector 14 and respond for performing communication with the interrogator 11 The interrogator antenna 12 is arranged in such a way that the reflecting surface 15 is oriented to a first focal point 16 of the reflecting surface 15 of the approximately elliptic radio wave reflector 14 and the radio tags 13 are arranged in the proximity of a second focal point 17 of the reflecting surface 15 of the approximately elliptic radio wave reflector 14 Since the interrogation signals emitted from the interrogator antenna 12 are reflected by the approximately elliptic radio wave reflector 14 and a region in which the interrogation signals are intensive is formed at the second focal point 17, the communication accuracy of the radio tag 13 positioned at the second focal point 17 with the interrogator 11 is improved COPYRIGHT: (C)2004,JPO

Method and device for calibrating a measuring system

Abstract: A measuring system including a measuring device with a laser tracker and an opto-electronic sensor having fixed positions relative to one another and an auxiliary measuring tool with a reflector and at least three light spots, is calibrated. The auxiliary measuring tool is rigidly coupled with an arrangement of auxiliary reflectors and is moved around at least two different rotation axes. Reflector and auxiliary reflectors are registered by the laser tracker and the light spots are registered by the opto-electronic sensor. From the data of the laser tracker, positions and orientations of the reflector arrangement relative to the laser tracker and from the data of the opto-electronic sensor, positions and orientations of the light spot arrangement relative to the opto-electronic sensor are calculated and the two rotation axes relative to the reflector arrangement and the light spot arrangement are calculated. Calibration data are calculated by equating corresponding rotation axes.

Multi-beam and multi-band antenna system for communication satellites

Abstract: An antenna system includes a reflector having a modified-paraboloid shape; and a multi-beam, multi-band feed array located at a focal point of the reflector so that the antenna system forms a multiple congruent beams that are contiguous. The system has a single reflector with non-frequency selective surface. The reflector is sized to produce a required beam size at K-band frequencies and is oversized at EHF-band frequencies. The synthesized reflector surface is moderately shaped and disproportionately broadens EHF-band and Ka-band beams compared to K-band beams. The synthesized reflector surface forms multiple beams each having a 0.5-degree diameter at K-band, Ka-band, and EHF band. The multi-beam, multi-band feed array includes a number of high-efficiency, multi-mode circular horns that operate in focused mode at K-band and defocused mode at Ka-band and EHF-band by employing “frequency-dependent” design for the horns.