Application of Reverberation Chamber for Radiated Emission Testing for Wireless Protection Toward Full-Scale Deployment of 5G System - Advantages and Challenges.

With the widespread deployment of high-frequency wireless communication systems such as the fifth generation (5G) system, high-frequency electromagnetic (EM) disturbances have become prevalent, requiring high-frequency compatibility testing of radiated emissions to prevent unintentional EM disturbance. Generally, radiated emission testing is typically performed in a fully anechoic room (FAR). However, the reproducibility of test results has become a problem owing to the increased insertion losses in the measurement system and the complicated directivity of the radiation from the equipment under test as the frequency increases. As an alternative to the FAR, a reverberation chamber (RC) has attracted attention in recent years as it allows high-sensitivity measurement with compact equipment. To perform radiated emission testing in the RC, it is important that the detection value given by the specified detectors is not affected by the characteristics of the RC. However, the disturbance waveform received in the RC is generally different from that in the FAR, resulting in a different detector response. In this study, the detectors and resolution bandwidths (RBWs) for radiated emission testing were used to investigate the conditions under which the detection values measured in the RC were equivalent to those measured in the FAR. For root mean square detection, the dependence of the mean detection values measured in the RC on the pulse width and RBW agreed well with those measured in the FAR. However, the relative changes in the mean detection values of the peak and average detectors in the RC were different from those in the FAR unless the time constant of the RC multiplied by RBW was sufficiently smaller.