The anechoic chamber is a large metal room lined with EM absorbers. The test object is illuminated by antennas driven by continuous wave (CW) or pulsed RF Amplifiers. The objective is to create a uniform EM field over the test object. The absorber suppresses reflections from the wall that would produce standing waves and, therefore, a non uniform field. This chamber provides adequate performance for all frequencies above 500 MHz. Field strength is calculated using the antenna gain and the net radiated power, as measured by means of directional couplers. Field strength and illumination spot size are inversely related and can be offset by the antenna's gain or its separation from the test object.
The chamber also has a 2 meter diameter vertical axis, remotely controlled turntable. The turntable is used to rotate the test object to provide different aspect angles.
Instrumentation is completely automated; signals from probes are transmitted over fiber optic cables to a digital recording system.
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