Research On Reconfigurable Intelligent Surface Assisted Space Shift Keying Technology

With the progress of 6G research,the demand for green communication performance is increasing in the future,and new physical layer technologies are constantly emerging,such as Reconfigurable Intelligent Surface(RIS)and Space Shift Keying(SSK).RIS changes the wireless environment in a more environmentally friendly way to bring energy-saving wireless communication solutions,while SSK carries information through antenna indexing at the transmitter,resulting in a new type of modulation with lower transmission and reception complexity.Note that there is currently relatively little research on joint RIS and SSK systems,and reconfigurable smart surfaces require the use of a large number of passive reflective components to change the wireless communication environment.Their auxiliary communication systems typically include multi hop links,making it difficult to analyze the performance of the system.The purpose of this thesis is to theoretically analyze the bit error rate performance of reconfigurable intelligent surface assisted space shift keying systems.The main work of this thesis is as follows:(1)Completed the communication performance analysis of two typical examples in the RIS-SSK system.For intelligent and blind RIS-SSK models,the average bit error rate under the maximum likelihood criterion is derived and compared.(2)A phase optimization algorithm of RIS reflection unit in RIS-SSK system is proposed.It aims to minimize the upper limit of joint error probability and adopts continuous convex approximation for constraint conditions.Secondly,the error rates of intelligent RIS-SSK,blind RIS-SSK,and the proposed RIS-SSK were compared.(3)A grouping optimization scheme of RIS reflection unit in RIS-SSK system is proposed.After the phase optimization algorithm is used to obtain the phase,a certain number of adjacent RIS reflection units are grouped.Then select and activate different packets and find the optimal transmission reflection mode combination to reduce the channel overhead and hardware cost.