;Multiple antenna techniques are commonly used in wireless communication systems to enhance transmission rates and provide transmit diversity. Spatial modulation(SM) is a type of multiple antenna technique that uses a single transmit antenna each time, transmitting additional data bits by selecting the transmit antenna. Among them, quadrature spatial modulation(QSM) is a form of spatial modulation, and it contains higher transmission rates than traditional spatial modulation. Later, someone proposed a high diversity quadrature spatial modulation, which can achieve transmit diversity of two. There are two sections in this thesis, both focusing on improvements of DA-QSM. In the first part, we select the real and imaginary antenna matrices jointly by bits to increase the data transmission rates of DA-QSM, and there are two bit¬ mapping methods. In the second part, the structure of the original thesis with a transmit diversity of two is extended to transmit diversity of three of four. We also compare it with space-time block coded spatial modulation(STBC-SM). DA-QSM has better error rates in the case of transmit diversity of two, while STBC-SM achieves superior error rates in the case of transmit diversity of four.
