Radome

A radome (which is a portmanteau of radar and dome) is a structural, weatherproof enclosure that protects a microwave (e.g. radar) antenna. The radome is constructed of material that minimally attenuates the electromagnetic signal transmitted or received by the antenna. In other words, the radome is transparent to radar or radio waves. Radomes protect the antenna surfaces from weather and conceal antenna electronic equipment from public view. They also protect nearby personnel from being accidentally struck by quickly rotating antennas.

Radomes can be constructed in several shapes (spherical, geodesic, planar, etc.) depending upon the particular application using various construction materials (fibreglass, PTFE-coated fabric, etc.).

When found on fixed-wing aircraft with forward-looking radar (as are commonly used for object or weather detection), the nose cones often additionally serve as radomes. In case of advanced aircraft systems like AEW&C, a rotating radome often called 'rotodome' is mounted on the top of the fuselage for 360 degree coverage. There are newer AEW&C configurations which instead of rotodome uses three antenna modules in triangular configuration inside radome (usually mounted on top of the fuselage) for 360 degree coverage such as Chinese and Indian AEW&Cs.

On rotary-wing and fixed-wing aircraft using microwave satellite for beyond-line-of-sight communication, radomes often appear as blisters on the fuselage. In addition to protection, radomes also streamline the antenna system, thus reducing drag.

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