A distributed paging mechanism over the X2 interface for all-wireless Networks of Small Cells

In this paper we propose a 3GPP-compliant distributed paging mechanism over the X2 interface for all-wireless Networks of Small Cells (NoS). An all-wireless NoS is a wireless mesh network that provides multi-hop connectivity amongst small cells, as well as access to functional entities in the mobile operator´s core network. The standard 3GPP paging procedure has been designed with traditional macrocell scenarios in mind. This raises scalability and network congestion issues in large-scale deployments of all-wireless NoS, where paging messages need to traverse a large number of small cells in order to reach the destination mobile terminal. Our proposal aims at reducing the total number of over-the-air paging transmissions and end-to-end paging delay needed to locate a terminal in a large NoS upon arrival of an incoming voice/data connection request. The scope of the proposed scheme is limited to the NoS, thus allowing all standard procedures and interfaces towards the core network to remain untouched. In addition, new network procedures and protocol messages have been designed to ensure a seamless integration with the latest release of 3GPP Technical Specifications. Simulation results show that our scheme outperforms the standard 3GPP paging mechanism in terms of total number of over-the-air paging transmissions, number of wireless channel accesses per byte, and end-to-end paging delay.