An apparatus and a method for measuring the receiver sensitivity of mobile and wireless terminals is disclosed, including a chamber to enclose the terminal to be tested (TUT). The chamber includes walls of an inwardly reflective material, rendering the walls reflective to electromagnetic waves, and at least one movable object within the chamber. The terminals include at least both a receiver and an antenna. The apparatus further includes an instrument to measure bit error rate (BER) or frame error rate (FER) connected to an antenna inside the chamber and set up to communicate with the TUT, wherein the received signal on the TUT shows fading obtained by moving the movable objects within the chamber.