Research And Realization Of NB-IoT Adaptive Scheduling Method

Towards the tide of 5G,communications technology is facing magnificent challenges and opportunities.IoT(Internet of Things)is a key component with broad prospects.Internet of Things,just as its name implies,is “the network that connects everyday objects”.It is based on Internet and traditional telecommunication network.And embedded with electronics,Internet connectivity,and other forms of hardware,physical devices can communicate and interact with others over the Internet.NB-IoT(Narrow Band-Internet of Things)is a key branch of IoT.It has many advantages,including low power,low cost,low delay demand,wide coverage,large number of users,rapid access,etc.It has broad application prospects,including automatic meter reading,intelligent street lamp,environmental monitoring,shared bicycle monitoring and so on.NB-IoT is now at the primary stage of commercial use.There are still many specific technical problems to be solved in the application process.The actual test in coverage and user signal quality indicates a far distance from being widely applied.This is because there are a large number of devices in NB-IoT.At present,the probability of successful transmission is mainly improved by repeated transmission,which seriously affects the efficiency of transmission and is not conducive to energy conservation and environmental protection.This paper mainly studies how to solve the problem of low transmission success rate and transmission efficiency of NB-IoT when a large number of low-speed terminals are accessed at the same time.Firstly,this paper introduces the existing packet scheduling methods of NB-IoT,and analyses the potential problems.Then,an adaptive scheduling method is proposed,which can adaptively adjust the size of transmission resources according to the retrieved physical layer time-frequency resource space.And it allocates alternative resources satisfying the threshold for users.According to the service delay of each user,the threshold is adjusted adaptively to reduce the threshold for users with longer waiting time.It makes it easier for users to get scheduled and get more fair service and quicker response.The realization method of adaptive threshold and the specific operation steps of adaptive scheduling are also given in this paper.In the simulation experiment,the proposed adaptive scheduling method is compared with the existing scheduling methods.The results show that the proposed method is superior to the existing scheduling methods in terms of cell throughput,resource utilization and scheduling complexity.