Effect of Cooperative Base Stations and Relay Stations for Disaster Recovery in MIMO Multi-cellular System

It has been shown that cooperative work of base stations (BSs) is effective for the disaster recovery, namely, even if BSs in some cells are destroyed and user terminals (UTs) should communicate with another BS in a far away distance, coordination scheme of survived BSs can mitigate the degradation of link quality in disaster cells. This paper extends this scheme to relay-aided case attempting the further performance improvement, after certain time has passed from disaster, the arrival of portable relay systems could be anticipated if they are previously prepared. Allocating one relay to each cell with a defect BS, the effectiveness of relay-aided processing and influence of related parameters are evaluated from the viewpoint of cooperative transmission through computer simulations. It is shown that the use of relay is not always preferred, but under certain condition, it brings significant performance improvement in disaster cells.