This Standard specifies the measurement methods for the reflectivity of electromagnetic wave absorbers (EMA) for the normal incident, oblique incident and each polarized wave in the millimetre-wave range. In addition, these methods are also equally effective for the reflectivity measurement of other materials: - Measurement frequency range: 30 GHz to 300 GHz - Reflectivity: 0 to -50 dB - Incident Angle: 0° to 80° Note This standard is applicable not only to those EMA which are widely used as the counter-measures against the communication faults, radio interference etc. , but also to those used in an anechoic chamber in some cases. EMAs may be any kind of material, and may have any arbitrary shape, configuration, or layered structure as pointed out below. Material: Conductive material, dielectric material, magnetic material Shape: planar-, pyramidal-, wedge-type, or other specific shapes. Layer structure: single layer, multi layers, or graded-index material