Spatial Modulation Based On Compressed Sensing In Multi-user System

Nodes in cooperative systems construct the virtual antenna arrays through sharing antennas with each other,which induces spatial multiplexing gain.Spatial Modulation(SM)conveys information using the indexes of activated antennas.It has characteristics of low-complexity and energy-efficient and can reduce the Inter-Channel Interference as well as the requirement of Inter-Antenna Synchronization in communication systems.Because unlike in the conventional modulation techniques,the transmit vectors of SM are sparsely populated.That is to say they have mostly zero values.This thesis analyzed the application of SM in Multi-User cooperative systems.In this treatise,we provided a general survey of cooperative technology and SM.and introduced a compressed sensing(CS)based SM system.We have analyzed and validated the system with experiments based on the GNU Radio an USRP.Through the analysis of data,we have got the influences of signal sparsity and the compressing dimension on Bit Error Rate(BER)performance.Moreover,we have also investigated the influence of power imbalance among antennas.Furthermore,considering that the wireless communication systems are particularly vulnerable to security attacks because of the inherent openness of the transmission medium,we have investigated the physical layer security from an information theory point in the cooperative systems.We have computed the lower and upper bounds of secrecy capacity and simulated the influences of the number of eavesdroppers and cooperative nodes through MATLAB.