Radome
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A radome (a
Radomes can be constructed in several shapes – spherical, geodesic, planar, etc. – depending on the particular application, using various construction materials such as fiberglass, polytetrafluoroethylene (PTFE)-coated fabric, and others.[2]
In addition to radar protection, radomes on
The air supported radome built by Walter Bird in 1948 at the Cornell Aeronautical Laboratory is the first pneumatic construction built in history.[4][2]
Use
A radome is often used to prevent ice and freezing rain from accumulating on antennas. In the case of a spinning radar parabolic antenna, the radome also protects the antenna from debris and rotational irregularities due to wind. Its shape is easily identified by its hardshell, which has strong properties against being damaged.
Stationary antennas
For stationary antennas, excessive amounts of ice can de-
Where radomes might be considered unsightly if near the ground, electric antenna heaters could be used instead. Usually running on
Radar dishes
For radar dishes, a single, large, ball-shaped dome also protects the rotational mechanism and the sensitive electronics, and is heated in colder climates to prevent icing.
The RAF Menwith Hill electronic surveillance base, which includes over 30 radomes, is widely believed to regularly intercept satellite communications. At Menwith Hill, the radome enclosures prevent observers from seeing the direction of the antennas, and therefore which satellites are being targeted. Similarly, radomes prevent observation of antennas used in ECHELON facilities.
The United States Air Force Aerospace Defense Command operated and maintained dozens of air defense radar stations in the contiguous United States and Alaska during the Cold War. Most of the radars used at these ground stations were protected by rigid or inflatable radomes. The radomes were typically at least 15 m (50 ft) in diameter and the radomes were attached to standardized radar tower buildings that housed the radar transmitter, receiver and antenna. Some of these radomes were very large. The CW-620 was a space frame rigid radome with a maximum diameter of 46 m (150 ft), and a height of 26 m (84 ft). This radome consisted of 590 panels, and was designed for winds up to 240 km/h (150 mph). The total radome weight was 92,700 kg (204,400 lb) with a surface area of 3,680 m2 (39,600 sq ft). The CW-620 radome was designed and constructed by Sperry-Rand Corporation for the Columbus Division of North American Aviation. This radome was originally used for the FPS-35 search radar at Baker Air Force Station, Oregon. When Baker AFS was closed the radome was moved to provide a high-school gymnasium in Payette, Idaho. Pictures and documents are available online at radomes.org/museum for Baker AFS/821st Radar Squadron.
Maritime satellites
For maritime satellite communications service, radomes are widely used to protect dish antennas which are continually tracking fixed satellites while the ship experiences pitch, roll and yaw movements. Large cruise ships and oil tankers may have radomes over 3 m in diameter covering antennas for broadband transmissions for television, voice, data, and the Internet, while recent developments allow similar services from smaller installations such as the 85 cm motorised dish used in the SES Broadband for Maritime system. Small private yachts may use radomes as small as 26 cm in diameter for voice and low-speed data.
Alternatives
An active electronically scanned array radar has no moving antenna and so a radome is not necessary.[2] An example of this is the pyramid which replaced the golfball-style radome installations at RAF Fylingdales.
Notes
- ISBN 9780850451634.
- ^ a b c Latifiyan, Pouya (August 28, 2022). "What is Radome?". Qoqnoos Scientific Magazine. 1: 13.
- ^ example of helicopter radome
- ^ Collado Baíllo, Isabel. "Walter Bird y las primeras construcciones neumáticas". Revista Europea de Investigación en Arquitectura. 20: 119–140.
- Gordon, J.E., The New Science of Strong Materials: 2nd Edition, Pelican, 1976.
External links
- Photograph of Mount Hebo while active overlooking Pacific Ocean