Never die network based on Cognitive Wireless Network and satellite system for large scale disaster

The Great East Japan Earthquake caused many casualties and radiation contamination from the Fukushima nuclear power plant, and many problems still remain in the disaster area. The communication network was severely affected by the earthquake. The network disconnection greatly delayed the rescue work and isolated many residential areas. This lack of robust network connection has become one of the major topics for any discussion of a Disaster Information Network System. This paper proposes a Never Die Network (NDN) which will consist of a Cognitive Wireless Network (CWN) and a Satellite Network. The best possible wireless links and routes are selected out of multiple wireless networks. This proposal, first of all, puts forward a cognition cycle which has a continuous network and user changing environment. Secondly, the optimal link selection will adapt the extended Analytic Hierarchy Process (AHP) method by a change of network environment and user policy during a disaster. Then, if the network environment or user environment can be changed, a proper route selection method can be conducted by the proposed extended Ad Hoc On-Demand Distance Vector (AODV) method with Min-Max AHP values. The simulation described in this paper contains an evaluation of the proposed methods by comparing a single ordinal wireless network system and a CWN for the disaster situations. The probable effectiveness of the proposed methods is discussed in this paper.