Configuration optimization of spatial modulation based on analytical bit error rate

Abstract:

Based on the analytical Bit Error Rate (BER) upper bound of Spatial Modulation (SM) systems, the optimal configuration of SM by allocating properly of the information bits onto spatial and signal constellation diagrams is investigated. The analytical BER upper bound of SM systems is derived by employing the moment generating function method. The tightness of the upper bound is verified by a comparison to Monte-Carlo simulations. The antenna number and modulation order of SM systems are optimized based on the upper bound of analytical BER. It is shown that, the Quadrature Phase Shift Keying (QPSK) signal mapping is the optimal constellation in SM systems in terms of BER. Also, a SM system with a given signal constellation can increase the transmission rate without sacrificing BER performance and adding Radio Frequency (RF) chains by increasing the number of transmit antennas.