Radiated emission measurement of small EUT by using a reverberation chamber

In radiated emission testing based on the measurement of the total radiated power by using reverberation chambers and TEM devices, the E-field strength is correlated with the radiated power by assuming the maximum directivity of the equipment under test (EUT). For small EUT, the directivity of a short dipole is often used. This paper describes how the emission E-field strength of small EUT was measured by using the substitution method in a reverberation chamber. These results were compared with those obtained using a GTEM-cell and an anechoic chamber. The experimental results showed an error caused by the assumption of the directivity in the correlated E-field strength; however, the reverberation chamber effectively measured the total radiated power. The total radiated power of the EUT with the directivity of a dipole measured by using a GTEM-cell was shifted 6 dB lower than that measured with a reverberation chamber.