Research On Discontinuous Reception And End Marker Format Design In 5G

With the continuous evolution of communication systems,5G system has begun to be commercialized,but the current 5G technology is not yet perfect,and there are still many directions worth studying in many new application scenarios.On the one hand,due to there is an increasing shortage of spectrum resources,the 5G systems will use unlicensed spectrum for data transmission.On the other hand,because the coverage of 5G networks requires a large number of base station constructions,in order to allow telecommunications operators to make a better transition,they will first use dual connection technology for non-independent networking.Currently,there are many technologies that need to be improved in these two scenarios of unlicensed spectrum and dual connectivity.This thesis focuses on the discontinuous reception(DRX)mechanism in unlicensed spectrum and how to ensure the sequential transmission of uplink data in dual-connection scenarios.Through mathematical modeling and simulation analysis,the corresponding optimization improvement and the advantages of the method proposed in this thesis are verified.The main research contents and innovation points are summarized as follows:(1)The thesis aims at the problem of large delay caused by LBT in the current DRX mechanism in the unlicensed spectrum,and proposes an optimization of changing the active time in DRX to the adaptive length according to the channel conditions.First,the system performance of the adaptive DRX mechanism is analyzed by establishing a timing model,and then simulation experiments prove that adaptive DRX can solve the problem of poor accessibility of user equipment in unlicensed frequency bands,and can effectively reduce the delay performance of the system in unlicensed frequency bands.At the same time,it does not increase excessive energy consumption.(2)The thesis focuses on how to ensure the sequential transmission of uplink data in the current dual-connection scenario.The main reason is that the current end marker based on the Service Data Adaptation Protocol(SDAP)header has some defects and proposes an end marker constructed using IP header,and simulation experiments have proved the feasibility of the proposed method.