A radome (radar dome) is an electromagnetically transparent protective shield that encloses mmWave Radar sensors and the antenna. It protects the mmWave antenna and electronics from external environment effects such as rain, sunlight, wind providing structural weatherproof enclosure. The radome minimally attenuates the electromagnetic signal transmitted or received by the antenna and as such should effectively be transparent to radio waves.

In some cases, a radome could be constructed as a lens that alters the beam characteristics intentionally. Such a radome or lens needs to be designed using electro-magnetic simulation tools in conjunction with the antenna and desired field of view in consideration.

Based on the needs of specific end equipment, radomes can be constructed in several shapes such as planar, spherical, and geodesic where the shape will have some influence on the radiation pattern or field of view and maximum achievable distance by radar sensor. The radome material choice, such as fiberglass, PTFE-coated fabric, and polycarbonate, is generally dependent on the targeted application environmental use.