Signal Processing for MIMO‐Based Chipless RFID Systems

Summary

This chapter presents signal processing techniques for successfully detecting the tag bits of a multiple input multiple output (MIMO)‐based chipless radio‐frequency identification (RFID) system. Two standard MIMO decomposing methods are presented, including zero forcing (ZF) equalizer, and the minimum mean square error equalizer (MMSE). Even though MMSE leads to better signal to interference plus noise ratio (SINR) performance, in the process it makes noise distribution to be bimodal, hence it no longer can be treated as Gaussian. On the other hand, the noise produced after ZF method still follows a Gaussian distribution subjected to an amplified noise. The chapter shows an experiment was conducted to measure the MIMO tag response using an arbitrary waveform generator (AWG) and an oscilloscope with a high sampling rate. The MIMO decomposing technique and the tag detection technique were implemented in MATLAB. The results obtained using both computer simulation technology (CST) and MATLAB simulations are presented and discussed.