Research On Spatial Modulation For BroadBand System In Correlated MIMO Channels

With the development of communication technology, the high speed of transmission data has become more and more important. Broadband system has become the basic needs for the future communications. Orthogonal frequency division multiple techniques (OFDM) and single-carrier frequency domain equalization (SC-FDE) have been widely adopted to combating multi-path propagation in broadband communication system. And they also have the features of simply hardware implementation and high spectrum efficiency. Multiple input multiple output (MIMO) technology which can increase the capacity of the communication system without any increasing of transmission power and system bandwidth,has become one of the key technologies to the communication system in recent years. However, the capacity and the bit error performance of system will decrease by the existence of the channel correlation. There exists mutual interference between the antenna channel (ICI) and inter-antenna synchronous (IAS) problems by using traditional MIMO technology. Spatial modulation (SM) technique becomes a new type of MIMO transmission technology which is able to avoid the problems. It is important and practical significance by adapting the SM technology in broadband communication systems. This paper focus on the research on spatial modulation for broad- band system in correlated MIMO channels. The main contents are as follows:Firstly, the characteristics of wireless MIMO channel has been studied. Then a channel modeling and simulation results has been given out. Furthermore, the relationship between the capacity and the number of systems and the channel correlation has been analyzed.Secondly, Spatial modulation technology and antenna/signal detection technology has been studied. A comparative analysis between SM with the traditional Alamouti space-time coding techniques, as well as V-BLAST spatial multiplexing has also been given. Simulation results show that SM system has better bit error rate (BER) performance at the same transmission rate.And then, the BER performance of the SM-OFDM broadband systems has been studied in wireless broadband MIMO channels. Not only in the uncorrelated Rayleigh multipath channel, but also in the uncorrelated Rician channel and in the correlated Rician channel.Theoretical analysis and simulation results show that the BER performance of system decreases when the channel correlation exists. In order to improve the system performance in the correlated channel, a new coding scheme was proposed, namely TCM encoding technique.The simulation results show the effectiveness of this program.Finally, the BER performance of the SM-SC-FDE system has also been studied. When the channel is correlated,TCM is also the same applies in the SM-SC-FDE system to decrease the impact of the channel correlation.