Quadrature spatial modulation with space‐time block‐coded CPM MIMO system

Abstract

Quadrature spatial modulation (QSM) is recently regarded as a technique to combat inter‐channel interference (ICI) for future wireless systems. In this paper, we consider a system of QSM combining space time block codes (STBC) and continuous phase modulation (CPM). In the system, the spatial constellation symbols are not expanded by two in‐phase and quadrature components, but represented by two STBC symbols. Moreover, we employ K‐means clustering algorithm to decrease the correlation of two transmit antennas. Then in the system, the bit error ratio (BER) performances are derived and evaluated for CPM and linear modulations (PSK, QAM). It is demonstrated that the proposed system has the advantages of BER performance and power spectrum density compared to its counterpart with linear modulations or without K‐means clustering of antennas.