Complex Generalized Quadrature Spatial Modulation for Large Scale MIMO System

Quadrature spatial modulation (QSM) maintains all of the advantages of spatial modulation but further improves upon its spectral efficiency by the logarithm base two of the number of transmit antennas. However, further improvement in terms of system complexity can still be achieved. This led to a generalized quadrature spatial modulation (GQSM) scheme. The proposed scheme is based on employing the transmit antenna combination to create unique groups at every transmission instant. In addition, a unique symbol is transmitted across the transmit antenna groups employed.GQSM reduced the required number of transmit antennas for high data rate in QSM by employing antenna grouping. Reduction in the imposed complexity for practical implementation of GQSM can still be achieved. Finally, the effects of low-complexity transmit antenna selection for the proposed scheme (CGQSM) is investigated to further reduce the computational complexity (CC) overhead. The selection is based on computing the channel amplitude and antenna correlation to eliminate poor channel(s). Monte Carlo simulation results demonstrate a trade-off between CC and reliability in comparison to the use of optimal antenna selection.