Antenna Location Design for Distributed-Antenna Based Secondary Systems

Distributed antenna system (DAS) can extend the cell coverage, increase the system capacity and decrease the other-cell interference. Dynamic spectrum access (DSA) can improve the whole system spectrum efficiency by allowing secondary system to access the licensed frequency bands. In this paper, a distributed-antenna based secondary system(DABSS) is considered, in which the antenna location is designed to obtain the maximum ergodic capacity of the secondary system. Particularly, a new metric called squared distance divided power criterion (SDDPC) is proposed to simplify the analysis of ergodic capacity. A linear DABSS is considered and the analytical solution of antenna location is derived using the squared distance divided power criterion. Simulation results show that the ergodic capacity using the proposed antenna location is closed to the maximum ergodic capacity.