Ionut Cardei, PI
Rapid response teams have to deal with unpredictable RF conditions, sketchy spectrum availability, and system incompatibility.
Collapsed buildings and damaged subway tunnels degrade signal quality inside. Power outages affecting cellular base stations are common after earthquakes and weather disasters. Ubiquitous smartphones with IEEE 802.11 adapters and GPS localization provide a powerful platform for opportunistic communication in difficult environments. Smartphones with IEEE 802.11 adapters configured in ad-hoc mode can form a wireless network that does not need any infrastructure to communicate end-to-end using multi-hop routes. Still, TCP/IP protocols only work if there is a continuously available path between endpoints. With intermittent connectivity, traditional IP MANET routing and transport protocols inevitably fail. The solution is to use Delay Tolerant Networking (DTN) techniques that can tolerate intermittent lack of end-to-end connectivity by storing and carrying messages.
This project develops DTN protocols for rapid response applications that has 802.11 ad-hoc networks self-organize and deliver packets end-to-end when the network topology is dynamic from node mobility and sporadic link availability. The protocols rely on cognitive networking techniques. Channel allocation is aware of availability from primary users (access points), and usage policies in order to prevent interference and to satisfy message quality of service. Message forwarding is scheduled based on contextual information derived from the user’s mission plan and resource availability. Conversely, the mission plan and node trajectory of some nodes is adjusted to serve communication demands using message ferrying.
These technologies will improve the effectiveness of communications for emergency response and for other ad-hoc scenarios using readily available smartphones when circumstances prohibit use of cellular or specialized government radio systems.