Performance Analysis And Modulation Scheme Design Of Non-Coherent Spatial Modulation

Spatial modulation(SM)is a promising multi-input and multiple-output(MIMO)technique.The SM only activates one antenna for data transmission in each time slot,and the antenna index also transmits additional information bits in a buried manner.Unlike traditional MIMO schemes with repetition codes and spatial multiplexing schemes,the antenna activation mode of the SM can reduce inter-channel interference(ICI)and avoid inter-antenna synchronization(IAS)problems.Therefore,in terms of bit error rate(BER)and energy efficiency,SM can achieve significant performance improvement.This paper mainly compares the performance of the index modulation in spatial domain,which is spatial modulation and its improved systems,such as generalized spatial modulation(GSM)and differential spatial modulation(DSM).The overall optimization goal is to reduce bit error rate of the system with the same transmission efficiency.In this paper,for the performance loss problem of non-coherent spatial modulation(NCSM)differential detection,a new power allocation concept is applied to the non-coherent spatial modulation system to reduce its bit error rate performance firstly.In order to verify the superiority of the proposed scheme,Monte Carlo simulation experiments are carried out on the NCSM system under the traditional amplitude phase shift keying constellation and the proposed scheme,the average symbol error rate formula of the above two systems is derived simultaneously.The system's average symbol error rate formula theoretically proves the correctness of its simulation results.In addition,the optimization problem of APSK constellation is also studied.The optimized constellation parameters are given by formula derivation.Finally,the simulation results show that the proposed BER performance of the proposed new APSK power allocation non-coherent spatial modulation system scheme(P-NCSM)is better than that of the traditional APSK-based non-coherent spatial modulation system.Subsequently,in the GSM system,due to its signal transmission matrix does not have the unitary characteristic and closed nature,the traditional differential detection cannot be implemented.Therefore,a differential scheme of generalized spatial modulation(D-GSM)is proposed.Firstly,the average bit error rate formula of D-GSM and GSM system is derived by theoretical performance analysis,and the corresponding simulation results are simulated by Monte Carlo method,so as to compare the bit error rate performance between the two systems.Then,the BER performance changes of the D-GSM system are simulated by setting different parameters.Secondly,the complexity of the two systems is analyzed,the formula is derived,and different parameters are set in the experiment for simulation comparison.The simulation results show that as the length of the transmitted frame increases,the BER performance of the D-GSM system is close to that of the coherent GSM system under equal spectral efficiency,and the D-GSM system has lower detection complexity.