Research On System Model And Detection Algorithm Based On Index Modulation

Index Modulation(IM)technology based on multiplexing technology is a new type of multi-angle modulation.The main idea is to further modulate data symbols using the effectiveness of the transmission medium.Index modulation technology creates transmission gaps by selecting different transmission media.On the premise of ensuring good performance,it can well resist Inter-Channel Interference(ICI)and solve the problem of transmission media synchronization.And index modulation also has the characteristics of adjusting transmitter power and spectrum efficiency,and is one of the major technologies for next-generation mobile communications.This paper mainly studies the performance of spatial index,ie spatial modulation system and its deformation system,such as generalized spatial modulation,orthogonal spatial modulation,etc.The overall optimization goal is to increase system transmission efficiency while reducing system interference,bit error rate and detection complexity.First of all,the problem of channel interference in transmitting different symbols under generalized spatial modulation and the complexity of receiver detection is studied.Based on the characteristics of index modulation,a new transmission scheme is proposed,in which the transmit antenna index value and transmission information bits are constructed into new transmission symbols,and then the mapping rules are adjusted and converted into the traditional constellation diagram.The system's active antenna information is hidden into the new modulation symbol,and then the transmitter uses the antenna selection algorithm to select the appropriate channel to achieve multi-antenna transmission anti-interference purposes.The reconfigured system will generate different structural symbols due to the sequential order of antenna selection,which can make full use of bits to select the redundancy of the antenna and improve the signal transmission rate.Each slot can transmit 2 to 3 bits more than conventional generalized spatial modulation.Since the receiver does not need to detect and activate the antenna combination like the conventional GSM,it only needs to detect the modulation symbol in the expanded constellation diagram to obtain the activated antenna information and the loaded transmission information,so that the search range is reduced and the detection complexity is reduced.Afterwards,for the problem that the orthogonal space modulation system has receive diversity but no transmit diversity,combined with the system characteristics of the space time shift keying system,a transmit diversity orthogonal space modulation system is proposed.The new system converts the activated antenna into an active space-time matrix to achieve transmit diversity and improve system performance.Because the new system uses the maximum likelihood algorithm to detect the complexity is too high,then a spherical decoding algorithm that changes the search range with the activation scheme is proposed.The new system uses this spherical detection to achieve the same performance as conventional orthogonal spatial modulation using maximum likelihood detection at high signal-to-noise ratios,but with a 15% reduction in detection complexity.