The radio anechoic chamber provides a free-space environment for radio wave propagation. It is used for testing radio navigation equipment before field experiments. It is also used for antenna pattern measurement.

    The anechoic chamber is built in a shielded box. Its inside ceiling, walls and floor are covered by electoromagnetic absorbers, because reducing interference improves measurement accuracy.

    Interference occurs because of outside sources and the reflection of signals under measurement from the inside surfaces and parts of the chamber. Low leakage is also a requirement.