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Standard and nonstandard types of radome wall structures are discussed to aid in determining practical design concepts for radar systems operating at Ka-band frequencies. Transmission efficiencies of selected radome panels are illustrated and compared for a hypothetical radome design problem.

It has been demonstrated that the ribs of the CW-396A radome have a negligible effect on the L-band elevation plane radiation pattern and consequently on the altitude error curves for the air-search radar discussed in Part 2 of this report (RADC-TR-215). In particular, the radome produces grating lobes that are approximately 30 dB below the main beam level.

This is quarter wavelength antenna protected by a radome. Use a wire (e.g 8.6 cm for 869.85 MHz) soldered to the printed circuit board. Openscad file is provided so you can change the dimensions if you change the frequency. The radome can be glued to the pcb. You can see a picture with and without the radome.

This paper presents a measurement system used for w-band complex permittivity measurements performed in NASA Langley Research Center's Electromagnetics Research Branch. The system was used to characterize candidate radome materials for the passive millimeter wave (PMMW) camera experiment. The PMMW camera is a new technology sensor, with goals of all-weather landings of civilian and military aircraft. The sensor is being developed under a NASA Technology Reinvestment program with TRW, McDonnell- Douglas, Honeywell, and Composite Optics, Inc. as participants. The experiment is scheduled to be flight tested on the Air Force's 'Speckled Trout' aircraft in late 1997. The camera operates at W-band, in a radiometric capacity and generates an image of the viewable field. Because the camera is a radiometer, the system is very sensitive to losses. Minimal transmission loss through the radome at the operating frequency, 89 GHz, was critical to the success of the experiment. This paper details the design, set-up, calibration and operation of a free space measurement system developed and used to characterize the candidate radome materials for this program.

UNMANNED AERIAL VEHICLE RADOME

Radome mount for cheap ADS-B antenna

This remix was done to eliminate the need for separate PVC and cap parts. Removed the through mounting holes and added a radome section. Also lengthened the mounting section as mine has to be mounted a bit down the mast. The additional length will pull it away from the mast. Build with 68mm of wire on the center pin of a PL259 or Type N connector. This will go inside the radome. Add 4 radials of 68mm off each of the mounting holes, bent at a 45-degree angle. The mounting holes are 15mm deep. This is a typical ground plane antenna. I am surrounded by trees on my property, but this little antenna performs well. My test part was printing with PLA, but can use PETG if used outdoors. Spray paint will seal the PLA as well.

This Volume 4 of four volumes presents 140 measured far-field patterns and boresight error data for eight combinations of three monopulse antennas and five tangent ogive Rexolite radomes at 35 GHz. The antennas and radomes, all of different sizes, were selected to provide a range of parameters as found in the applications. The measured data serve as true data in the parametric investigation of radome analysis methods to determine the accuracies and ranges of validity of selected methods of analysis. (Author)

Measurement errors of radiometric brightness temperature as function of lossy radome

The problem of radome diffraction in radar-controlled homing missiles at high speeds and high altitudes is considered from the point of view of developing a control system configuration which will alleviate the deleterious effects of the diffraction. It is shown that radome diffraction is in essence a kinematic feedback of body angular velocities which causes the radar to sense large apparent line-of-sight angular velocities. The normal control system cannot distinguish between the erroneous and actual line-of-sight rates, and entirely wrong maneuvers are produced which result in large miss distances. The problem is resolved by adding to the control system a special-purpose computer which utilizes measured body angular velocity to extract from the radar output true line-of-sight information for use in steering the missile. The computer operates on the principle of sampling and storing the radar output at instants when the body angular velocity is low and using this stored information for maneuvering commands. In addition, when the angular velocity is not low the computer determines a radome diffraction compensation which is subtracted from the radar output to reduce the error in the sampled information. Analog simulation results for the proposed control system operating in a coplanar (vertical plane) attack indicate a potential decrease in miss distance to an order of magnitude below that for a conventional system. Effects of glint noise, random target maneuvers, initial heading errors, and missile maneuverability are considered in the investigation.

This report presents the results of w-band complex permittivity measurements performed in NASA Langley's Electromagnetics Research Branch. The test articles included in the permittivity study were flat panels of materials which are under consideration for use in a radome for the Passive Millimeter Wave Camera (PMMWC) flight experiment. This experiment is scheduled to fly on the Air Force's 'Speckled Trout' aircraft in late 1997. The radome design is very important because the PMMWC can tolerate only a small amount of electromagnetic loss through the radome. A free space measurement system was used to obtain complex reflection and transmission coefficients of the samples. The frequency of interest was 89 GHz, so measurements were performed over a range of 79 to 99 GHz. The transmission and reflection coefficients were used, along with the measured sample thickness, to calculate complex permittivity over the frequency range. The material samples measured in this study can be divided into four categories: skin materials, core materials, coating materials, and layered samples.

This report studies the transmission properties of metallic radome configuration of two slot arrays consisting of three-legged elements imbedded in three dielectric layers. The purpose is to design a bandpass filter with as large a bandwidth as possible while still maintaining a constant bandwidth for all angles of incidence. (Author)

This report studies the transmission properties of metallic radome configuration of two slot arrays consisting of three-legged elements imbedded in three dielectric layers. The purpose is to design a bandpass filter with as large a bandwidth as possible while still maintaining a constant bandwidth for all angles of incidence. (Author)

This report describes a computer analysis tool for calculating the electrical transmission and reflection properties of a multiwall radome. The radome program may be used with a suitable antenna program to estimate the effects of the radome on the antenna pattern. The analysis tool is comprised of two programs, a radome-geometry program, RADOME, and a flat-panel analysis program, WAVES2. The geometry program calculates the incidence angle for each ray (a ray represents the radiated RF power from each antenna element) at the radome wall. The output data from the geometry program, RADOME, serves as input to the flat-panel program. The flat-panel program then calculates the electrical transmission and reflection parameters of the radome for each ray. These parameters may then be used with a suitable free-space antenna pattern simulation program, and the resultant antenna pattern in the presence of the radome can be computed.

This Volume 4 of four volumes presents 140 measured far-field patterns and boresight error data for eight combinations of three monopulse antennas and five tangent ogive Rexolite radomes at 35 GHz. The antennas and radomes, all of different sizes, were selected to provide a range of parameters as found in the applications. The measured data serve as true data in the parametric investigation of radome analysis methods to determine the accuracies and ranges of validity of selected methods of analysis. (Author)

The problem of radome diffraction in radar-controlled homing missiles at high speeds and high altitudes is considered from the point of view of developing a control system configuration which will alleviate the deleterious effects of the diffraction. It is shown that radome diffraction is in essence a kinematic feedback of body angular velocities which causes the radar to sense large apparent line-of-sight angular velocities. The normal control system cannot distinguish between the erroneous and actual line-of-sight rates, and entirely wrong maneuvers are produced which result in large miss distances. The problem is resolved by adding to the control system a special-purpose computer which utilizes measured body angular velocity to extract from the radar output true line-of-sight information for use in steering the missile. The computer operates on the principle of sampling and storing the radar output at instants when the body angular velocity is low and using this stored information for maneuvering commands. In addition, when the angular velocity is not low the computer determines a radome diffraction compensation which is subtracted from the radar output to reduce the error in the sampled information. Analog simulation results for the proposed control system operating in a coplanar (vertical plane) attack indicate a potential decrease in miss distance to an order of magnitude below that for a conventional system. Effects of glint noise, random target maneuvers, initial heading errors, and missile maneuverability are considered in the investigation.

The B757 Radome on positioner. Photographed in building 1299, room 150.

ICE ON RADOME

This report documents the Operational Test and Evaluation (OT&E) Operational testing performed on the Type II, Fixed Ground Antenna Radome (FGAR) First Article. The Type II FGAR is used at Mode Select Beacon System (Mode S) and Air Traffic Control Beacon Interrogator (ATCBI) beacon only sites (BOS). This testing was performed on the Federal Aviation Administration's (FAA) Central Region's Rockville BOS Facility (QJM), Nebraska (NE). The testing was limited to electromagnetic performance characteristics evaluation. In conjunction with the FGAR installation, the ATCBI-5 was replaced with a Mode S. Electromagnetic performance data was collected for evaluation by the Minneapolis (ZMP), Denver (ZDV), and Kansas City (ZKC) Air Route Traffic Control Centers (ARTCC). The testing showed no degradation of the antenna electromagnetic patterns. The testing determined that the FGAR meets the Operational Suitability and Operational Effectiveness requirements of the FAA.

This report summarizes the analysis conducted to determine the thermal stresses in a ceramic radome subjected to laser irradiation. It describes the thermal analysis conducted to determine the thermal loading in laboratory test discs and in a full-size radome model based on a "Sparrow" scribes the structural analysis of both structures based on the thermal loading derived and compares these results to a one-dimensional thermal and thermal stress analysis.

The report describes the results of a research program to select, analyze, and evaluate various radome materials and configurations in order to determine a preliminary design of a radome which can be used with advanced RF seekers operating over the 8.0 to 18.0 GHz frequency band and physically constrained for operation in a five-inch (outside) diameter missile.

This report documents the usage and applications of the Ray Trace Formulation Radome Analysis Computer Program (RTFRACP) to the BMD ENNK Program. Methodology for applying the program to a generic millimeter wave radome is presented. Data is given to illustrate the effect of temperature, erosion, ablation and frequency variation on radome boresight error.

A need has arisen for radomes suitable for use in areas where wind velocities of 150 mph are likely to be encountered. It was decided that a wind tunnel program would be the optimum method of obtaining tower loading and other data required for design purposes. It was decided that the following parameters would be investigated: wind speed, internal inflation pressure, angle of attack and Reynolds' number.

The B757 Radome on positioner. Photographed in building 1299, room 150.

UNMANNED AERIAL VEHICLE RADOME

UNMANNED AERIAL VEHICLE RADOME

sent by Steven Rowell at 18.07.2008 12:59:19

Data is given on the properties of radome materials in use and those which are considered candidates for possible application in avionics systems. Inorganic and organic radome materials used for walls, core, and coatings are reported on together with electrical, mechanical, thermal and environmental properties. The report has aimed to include a comprehensive description of radome materials, particularly for airborne microwave application.

A Fortran computer program is described for computing the effects of a tangent ogive radome on the receiving patterns and boresight directions of a monopulse antenna. The analytical method based on ray tracing, main program, and 34 subroutines are thoroughly documented. Four test cases and their results in the form of printouts, pattern plots, and near-field graphs are presented. (Author)

This report contains a summary of rain erosion results obtained for high-purity slip-cast fused silica (SCFS) models on sleds at Holloman Air Force Base, New Mexico. This effort, which was initiated to evaluate the rain erosion behavior of SCFS as a function of velocity and angle of incidence was completed with good correlation of results. The test were performed in artificial rain at average velocities between 1270 and 1740 m/sec (Mach 3.7 and 5.0). Right circular cone models having semivertex angles of 15, 19, 22.5, 25, 27.5, and 30 degrees were tested. A special test vehicle and sample design were utilized to avoid sled vibration-induced failures that are common to small samples of brittle ceramics at velocities near Mach 5. A unique feature of the sled test vehicle is its capability of testing seven cone frusta, thereby simulating actual radome fore body shapes. The sample design and special mounting technique resulted in obtaining correlatable erosion data which were free of spurious mass losses caused by sample fracture and edge effects. Because SCFS has low fracture toughness and relatively poor rain erosion resistance under severe conditions, other candidate ceramic and plastic radome materials were tested concurrently in the interest of finding a tougher structure. However only those results for SCFS are presented in this report.

UNMANNED AERIAL VEHICLE RADOME

BURNER RIG TESTS IN BOTH HEATING AND COOLING POSITIONS - RADOME CERAMIC MISSILE - EROSION RIG - THERMAL BARRIER COATED SAMPLE

BURNER RIG TESTS IN BOTH HEATING AND COOLING POSITIONS - RADOME CERAMIC MISSILE - EROSION RIG - THERMAL BARRIER COATED SAMPLE

BURNER RIG TESTS IN BOTH HEATING AND COOLING POSITIONS - RADOME CERAMIC MISSILE - EROSION RIG - THERMAL BARRIER COATED SAMPLE

In a previous report, details of the analysis of a curved dielectric radome using geometrical optics were considered for a point source. In this report, we first consider the transmission of a spherical or plane wave through a curved dielectric interface. The transmitted field is proportional to the product of the conventional Fresnel's transmission coefficient and a divergence factor DF, which describes the cross-sectional variation (convergence or divergence) of a ray pencil as the latter propagates in the transmitted region. The factor DF depends on the incident wavefront, the curvatures of the interface, and the relative indices of the two media. We give explicit matrix formulas for calculating DF, illustrate its physical significance via examples, and point out an erroneous solution in the recent literature.

An analysis of the aerodynamic and stress problems encountered in the design of radome shells is presented in two volumes. This volume discusses the aerodynamics with special emphasis on the calculation and reduction of heat transfer to the radome. Results are shown for Mach numbers up to 7 and altitudes to 150,000 eet. A chapter on shock layer ionization is also included in which the flow field about a typical radome configuration is studied for Mach numbers of 15 and 20 at altitues of 150,000 and 200,000 feet.

This Volume 4 of four volumes presents 140 measured far-field patterns and boresight error data for eight combinations of three monopulse antennas and five tangent ogive Rexolite radomes at 35 GHz. The antennas and radomes, all of different sizes, were selected to provide a range of parameters as found in the applications. The measured data serve as true data in the parametric investigation of radome analysis methods to determine the accuracies and ranges of validity of selected methods of analysis. (Author)

The status is described of a research program whose objective is to determine the accuracies of various methods of radome analysis as functions of antenna size and placement, radome size and shape, and wavelength. The analytical methods used and the experimental program to establish true data are described concisely. (Author)

ICE ON RADOME

Radomes constructed from a Kevlar/polyester composite are being produced for U.S. Air Force Milstar terminals for use on airborne platforms. The MITRE Corporation is prototyping a computer-based training system that will train nondestructive inspection (NDI) personnel how to inspect Milstar radomes using ultrasonics. The Trainer uses state-of-the-art multimedia tools to integrate ultrasonic signals, simulated test equipment, microscope images, digitized video, talking help agents, and a database of radomes with electronically configurable flaws. The resultant training environment is both visual and highly interactive. This document describes the Trainer prototype in terms of its functions, design architecture, and development tools.

This document defines the Type II Fixed Ground Antenna Radome (FGAR) Operational Test and Evaluation (OT&E) operational test procedures that will be performed at Federal Aviation Administration (FAA) field facilities.

The objectives of this program are: to investigate and evaluate the various grades of BeO available for radome fabrication; to determine the optimum compositions and material preparation methods for forming; to utilize pressure casting as a means of forming BeO and determine the material and process parameters which control the properties of the finished pieces; to fabricate prototype radomes using the materials and process information established, so as to reduce final grinding to a minimum.

This paper present the design of a circular patch microstrip antenna with enhancement in terms of bandwidth and gain using a dielectric double negative (DNG) split ring metamaterial radome. This radome is positioned on top of the CP antenna operating from 5.2 GHz to 6.4 GHz. The metamaterial radome comprises of two alternate split rings of negative permittivity, permeability and refractive index. The circular microstrip antenna bandwidth of 430 MHz has been realized by the presence of DNG metamaterial radome compared to 220 MHz without the radome. The gain has been increased as well from 1.84 dBi to 3.87 dBi.

The ADS-B radome by markend is a brilliant design - looks really smart and fits really nicely with no soldering necessary to fit everything together. My only issue with it was the mount, which I wanted to modify so that it would fit on top of a small 48mm diameter satellite dish mast (https://smile.amazon.de/gp/product/B0052AUX50/ref=ppx_yo_dt_b_asin_title_o02_s00?ie=UTF8&psc=1) which I mounted to my balcony rail. This way the coax cable goes down through the mast and out the bottom and I left a cutout to allow other cables to run up the mast and in under the antenna to the inside, where they can also be routed down and out. The mast attachment just pressure fits onto the top of the mast and then it has a bayonet style attachment to the antenna part.

Summary Airfoil antenna radom for S500 quadcopter. Receiver holder ★ Flysky FS-A8S 2.4G 8CH Berci the guinea pig :-)

Summary Airfoil antenna radom for S500 quadcopter. Receiver holder ★ Flysky FS-A8S 2.4G 8CH Berci the guinea pig :-)

Summary Airfoil antenna radom for S500 quadcopter. Receiver holder ★ Flysky FS-A8S 2.4G 8CH Berci the guinea pig :-)

Summary Airfoil antenna radom for S500 quadcopter. Receiver holder ★ Flysky FS-A8S 2.4G 8CH Berci the guinea pig :-)

The B757 Radome on positioner. Photographed in building 1299, room 150.

C130 RADOME TEST