MAC Protocol for Contacts from Survivors in Disaster Areas Using Multi-hop Wireless Transmissions.

We propose a simple multiple access control (MAC) protocol that allows survivors in disaster areas to establish contact to the base stations (BSs) provided by the rescue team. Our protocol relies on downstream broadcast single-hop wireless transmissions from the BSs to the survivors and upstream multi-hop wireless transmissions. For MAC, the protocol uses a combination of tree splitting and code division multiple access (CDMA). Compared to the single-hop approach for upstream transmissions, we show that the multi-hop approach can expend less transmission energy, especially when data aggregation is possible at relay points. In addition, the multi-hop approach requires less connection setup time. The energy and time efficiency makes the protocol attractive for communications for disaster management. [ABSTRACT FROM AUTHOR]