Research On Multi-scenario Access Technology For Satellite Internet Of Things

As people’s lives become more and more diversified,a variety of electronic terminal devices appear in every corner of people’s lives,a variety of devices can be connected to each other for information transmission has become people’s needs,in the face of the needs of this life,how to efficiently connect a large number of Internet of Things devices together for information interaction has also become a hot research topic.Existing cellular networks are difficult to support on such a large scale of Io T business,and it is imperative to expand resources in the field.Because of the wide distribution of Internet of Things terminals,and in some sparsely populated places there are a large number of terminals based on the above Internet of Things business distribution characteristics,in recent years,the proposed satellite Internet of Things can better solve these problems.How to connect the massive terminal to the satellite efficiently makes th e efficient operation of the system worth studying.This paper first analyzes the current research status of satellite Internet of Things at home and abroad on the satellite Internet of Things research trends,progress,and the access technology classifica tion,different access methods of the specific technology and its application to the satellite Internet of Things to introduce and analyze the existing situation.Secondly,it analyzes the multi-access technology in satellite Internet of Things,analyzes t he CDMA technology in orthogonal multi-access technology and SCMA technology in non-orthogonal multi-access technology,and analyzes the scope and scenarios applicable to satellite Internet of Things.In addition to the multi-access technology of the physical layer,this paper introduces the typical access technology of MAC layer in the satellite Internet of Things,and gives this paper’s random access method based on code channel for the specific scenario of satellite Internet of Things,the packet can be randomly selected for transmission by different code channels,when the number of code channels is more packet collision probability is lower;The performance analysis of this scheme verifies the advantages of multi-code channel for system performance improvement.Finally,the hybrid access method based on different resources such as code channel and time is analyzed,which is divided into grant-based and grant-free access from the strategy,and the resource is divided into two kinds of grant-based and grant-free access,different mixed mode selection is made according to different business scenario models,which gives the system great freedom and flexibility,verifies the feasibility of the scheme,and makes theoretical analysis and simulation verification based on the hybrid access of typical CDMA based on code channel division.