Reverberation chambers (RC) have been utilized for more than half century. Initially, they have been employed in measuring the EM properties of material before using in EMC performance of equipment, like immunity properties or interference. Recently, reverberation chamber has been introduced into the evaluation of over-the-air (OTA) performance of wireless devices, which include TRP, TIS and gain or efficiency of antenna. As compared with anechoic or other methods, RC method can reduce the cost of measurement devices, also increase the test efficiency of TRP. In order to further improve the testing efficiency of the reverberation chamber, this paper proposes an electrically controlled smart surfaces (ESS) which could switch on or off to improve the uniformity of electromagnetic field inside chamber.