Radio Environment Map based architecture and protocols for mobile ad hoc networks

In emergency scenarios, when multiple rescue and security actors have to quickly deploy their networks in the same area, interference among networks and lack of frequency resources could strongly impact networks activities and be at the origin of less efficient emergency operations. More generally, to allow the coexistence of mobile autonomous ad hoc networks that share the same frequency resources is a crucial problem to solve, that can be very challenging due to interference they might generate to each other. The introduction of Radio Environment Map (REM) concept can be a helpful mean to face this problem. In this paper we propose an adaptation of the REM concept to the ad hoc constraints. We elaborate a REM-based system architecture and we develop a protocol that enables the deployment and the coexistence of several ad hoc networks that share a limited amount of frequency resources in the same area. The need to optimize the use of frequency resources by reducing signalling load, coupled with the objective to keep networks autonomous, led us to the elaboration of a two-level REM based architecture. In addition to a Global REM (G-REM), to which all networks can have access in order to report and obtain data, each network has a Local REM (L-REM), that pilots nodes with measurement capabilities (MCDs), collecting and processing information and interfacing (when necessary) with G-REM. A protocol that permits to construct and to feed the L-REM as well as to pilot the measurement activities of the nodes is developed in the paper. The proposed protocol takes also into account the problem of coordination of resource allocation activities in each network through a Radio Resource Manager (RRM), integrating in the defined signalling messages both RRM and L-REM operations.