OpenAirMesh—An Experimental Platform for Cooperative Mesh Networks

OpenAirInterface (www.openairinterface.org) is an experimental real-time hardware and software platform for airinterface experimentation. It comes in two configurations, cellular and cooperative mesh network topologies. Here we present the platform architecture for mesh networks. The network is organized in clusters, where dynamically-allocated cluster-heads (CHs) manage radio resources. CHs are typically the bestconnected nodes in a particular geographical area and are synchronized in a distributed fashion by using special relaying nodes on the cluster boundaries. The physical (PHY) layer of the platform targets WiMax and UMTS LTE like networks and thus uses MIMO-OFDMA as modulation and multiple access technique. The current hardware supports 5MHz bandwidth and two transmit/receive antennas. The media access (MAC) layer of the platform supports an abundant two-way signalling for enabling collaboration, scheduling protocols as well as traffic and channel measurements. The platform is designed for a full software-radio implementation, in the sense that all protocol layers run on the host PCs under the control of a Linux real time operation system. Applications of the OpenAirMesh platform include demonstration of broadband ad hoc communications systems for public safety units as well as demonstration of collaborative communication in a cognitive radio system. In addition to the basic architecture of OpenAirMesh we highlight some application examples.