An Enhanced Random Access Algorithm Based on the Clustering-Reuse Preamble Allocation in NB-IoT System

As a new wireless access technology, Narrow Band IoT (NB-IoT) enables low-power wide-area coverage services and can be applied to many domains. Emerging applications such as smart traffic, shared bicycles and shared cars have put forward more stringent requirements for connectivity. In order to get higher QoS, an enhancement access algorithm is proposed for the complex service scenario of NB-IoT, in which the network terminals are clustered based the distance from base station and terminal traffic intensity, and allocated reuse preamble code to improve network access capacity. The capacity is modeled and analyzed to evaluate the enhanced access algorithm based on clustering-reuse preamble allocation (ERA-CRPA). The experimental results show that the ERA-CRPA can effectively reduce the probability of random access preamble collision, further improve the access efficiency and increase the equivalent capacity of NB-IoT network.