Generalized Quadrature Space-Time Modulation for Ambient Backscatter Communication

In this letter, we propose a generalized quadrature space-time modulation (GQSTM)-Backscatter scheme for ambient backscatter communication (AmBC), which can provide both diversity gain and higher data rate. An efficient and simplified dispersion matrices (DMs) design method is proposed to avoid parameter optimization and DMs search while providing hardware simplicity. Furthermore, a low-complexity and near-optimal detector named threshold and error correction-assisted minimum mean square error (TEC-MMSE) detector is proposed. Simulations and theoretical analysis demonstrate that the GQSTM-Backscatter scheme outperforms related schemes in terms of bit error rate (BER) performance.