Figure 2
From: On the performance of MIMO RFID backscattering channels
An illustration of the MIMO RFID channel signaling scheme. In a passive RFID system, the coding and modulation are done by the tag circuits at the tag side and the reader transmitting antennas actually act as charging devices. The modulation and coding in the middle way of a cascaded channels make the RFID channel different from other forms of cascaded channels.