A sectored cell architecture in two-hop relay-enhanced OFDMA cellular networks

In this paper, a novel cell architecture in relay-enhanced Orthogonal Frequency-Division Multiple Access (OFDMA) cellular networks is proposed. By spatially reusing the spectrum in the same cell, the frequency efficiency is enhanced, while the co-channel interference is reduced by dividing the coverage of both the base stations (BSs) and the relays into sectors, thus the MSs at the cell edge can attain higher Signal-to-Interference-plus-Noise Ratio (SINR). Simulation results illustrate that the proposed architecture can improve the system spectral efficiency, the SINR of cell edge MSs, and the number of MSs with quality of service (QoS) guaranteed significantly, while maintaining a low outage ratio, compared with the relay-based cell architecture that only dividing the coverage of the BSs into sectors.