Analysis And Implementation Of The MAC Layer Of Narrow Band M2M

With the development of technology,M2M(communication between machines)business scope is more and more widely.The number of M2 M connections is also rapidly increasing.Studies have shown that it is expected to have 17 billion M2 M connections in 2020.Among these connections,10 billion is for similar smart business.These services are usually in the wireless coverage area(basement,garage,etc.).They transmit data with low rate(less than 10kpbs)and low data volume(several times a day)and the terminals are with low power consumption and low cost.Cellular network can provide excellent coverage,support mobility and high security and there are many infrastructures.These make the cellular network become a promising direction of M2 M communication network.Therefore,optimization for cellular network technology and research for M2 M communication network will bring a major breakthrough for the development of IoT(Internet of Things,IoT).3GPP proposed technical solutions for cellular IoT,including NB(Narrow Band)cellular technology,which has the characteristics of ultra-low data transfer rate,higher coverage,lower cost and it can coexist with existing cellular network technology.The main content of this page is the design and implementation of MAC(Medium Access Control)layer in NB M2 M base station tester.In order to test the performance of the base station,this tester designs multi-user systems to simulate interaction with the base station in the MAC layer.Firstly,as the ultra-low rate and ultra-small amount of data in NB M2 M,this paper gives the user side MAC layer protocol design programs from three aspects of air interface protocol architecture,radio resource management and data transmission and focus on the analysis of the M2 M terminal random access optimized design and data transmission acknowledgment mechanism.Then,the combining with MAC layer protocol,it analyzes the difficulties to achieve a multi-user system in the MAC layer and points that the system must meet the need of best MAC layer scheduler,independent with the number of users,little impact between layers and low coupling degree of code.Finally,it gives the realization scheme of a multi-user system from technical analysis,framework design,interface design,functional design and other aspects.At the same time,it shows the protocol test results.