Fig. 2

Schematic view of the measurement setup. The UL transmission (solid lines) is wired, while the DL transmission (dotted lines) is wireless. For both UL and DL transmission, we were using OFDMA. During the experiment, we change the transmit power of UE 0 (indicated by the red solid line) and observe the receive power difference between UE 0 and UE 1 at a spectrum analyzer (indicated by the green box) and the BER at the BS. We use the same hardware for BS and UE; however, their firmware is different