Research On The Key Parameters Of Generalized Spatial Modulation Over Fading Channels

In order to meet the growing demand for data traffic, the future of wireless mobile communications system should have significant features of high spectral efficiency, high reliability, and energy-saving green. Multi-input multi-output (MIMO) transmission technology use multiple antennas to build space independent channels, combined with space-time coding techniques dramatically improve the system spectral efficiency and link reliability. However, since MIMO system is not only configure independent radio frequency channels (RFC) for each transmitting and receiving antennas which consume a lot of static power, but also require to maintain strict synchronization between each RFC, it is difficult to simultaneously achieve green and energy-saving requirements. As an expansion of spatial modulation, generalized spatial modulation (GSM) system can get high spectrum efficiency (SE) and energy efficiency (EE) with low signal processing complexity and hardware cost by effectively overcoming the above problems. Research on how to design the key parameters of GSM and analysis the performance of GSM system are effective ways to promote the system from theory to application.In this paper, we propose effective methods on how to design the key parameters of GSM system from two perspectives including maximizing energy efficiency and minimizing average bit error probability. The main work and innovations are:1. Optimally design the number of RFC according to the criterion of maximizing EEThe number of RFC is one of the key factors of restricting the EE of GSM. To improve the EE of the system, in this paper, we optimally design the number of RFC according to the criterion of maximizing EE, and then we propose an energy efficiency optimization generalized spatial modulation system named EE-GSM system. We first give the EE of GSM according to the MIMO system capacity and EARTH power consumption model. Based on that, we combine the successively reduced antenna selection algorithm to elect feasible antenna subset, and then get the optimal number of RFC, so as to complete the configuration of the whole system. Simulation results show that the EE performance of the proposed EE-GSM is superior to the existing AS-MIMO system, GSM system and SM system regardless of the channel condition is independent or correlated.2. Optimally design the modulation set based on minimizing the average bit error probabilityGiven the SE and EE of GSM, spatial modulation set and symbol modulation set are the key parameters of restricting the receive performance of GSM. To improve the receive performance of the system, we want to optimally design the modulation set based on minimizing the average bit error probability, and we propose a oriented transmission optimization generalized spatial modulation named TOGSM. In this paper, we first analysis the ABEP theoretical performance of GSM system over spatial correlated fading channels, and derived the upper bound and the high SNR approximate expression of the ABEP. Based on that, we optimal design the spatial modulation set and symbol modulation set by solving the optimization of minimizing ABEP. So as to complete the configuration of the whole system. The simulation results show that the proposed TOGSM system can only use the correlated information of the channel to configure the key system parameters, and get much better ABEP performance than the existing fixed-GSM system, V-BLSAT system, GSM system and GSSK system.