iCAR: an integrated cellular and ad-hoc relay system

Ever increasing data traffic and limited capacity are major causes for congestion in current cellular systems. This paper presents a new architecture for the next generation wireless systems based on the integration of the cellular infrastructure and modern ad-hoc relaying technologies. The new architecture can efficiently balance traffic loads between cells by using ad-hoc relay stations (ARS) to relay traffic from one cell to another cell dynamically. This can not only increase a system's capacity cost-effectively, but also reduce transmission power for mobile hosts, and provide services for shadow areas. In this paper, we present the architectural concept including its basic operations and principal benefits. We also propose a seed-growing approach for ARS placement, and discuss the upper bound on the number of seed ARSs needed in the system. We evaluate the performance improvement of the new architecture through analysis and simulations.