Bandwidth-Efficient Generalized Differential Spatial Modulation

Differential spatial modulation (DSM) can transmit additional data bits by selecting indexes of antennas without the pilot overhead and increasing radio frequency circuits and power consumption. DSM is extended to generalized DSM (GDSM) where more than one transmit antennas are activated each time. However, the transmission rate of the existing GDSM scheme is low. In this paper, we propose a new GDSM scheme that uses symbol interleaving on differential space-time modulation. The number of interleaving patterns is derived, and interleaving patterns with transmit diversity two are created as well. By selecting the interleaving patterns, the proposed scheme has higher data rates than the existing GDSM scheme. We also propose low-complexity detectors for both schemes. Theoretical analysis and computer simulation both show that the proposed scheme has satisfactory error performance.