A random access scheme based on dynamic allocation of PRACH resources for smart grid communication

The core concept of smart grid (SG) is to achieve the intellectual scheduling and control by applying modern information communication and other advanced technology. Many countries choose Long-Term-Evolution (LTE) system as the access network communication of power grid due to its high reliability, high transmission efficiency and mature technology. In the background of SG, it tends to appear that massive devices apply for access resources simultaneously, which will cause Radio Access Network (RAN) congestion, delay increasement, packet loss and even service interruption. Therefore, it is necessary to make some adjustments and improvements on the LTE random access control mechanism in order to achieve the large amounts of access and the reasonable utilization of resource. In this paper, we propose a random access mechanism based on dynamic allocation of Physical Random Access Channel (PRACH) resources. The method will adjust the PRACH configure index according to the overload of high-priority so that the RAN congestion can be alleviated. The simulation results show that this method can effectively improve the access success rate, and more importantly, it greatly reduces the access delay of high-priority. In short, the proposed method solves the massive power grid terminal access problem to some extent while taking into account users' Quality of Service (QoS) requirements.