Route Selection Strategies in Cellular Networks with Two-Hop Relaying

In the relay enhanced cellular network (REC), user terminals can flexibly select transmission routes to get service. This paper investigated the effect of route selection schemes on the system performance of REC. Besides the traditional schemes based on signal power and signal-to-interference-plus-noise-ratio (SINR), we evaluated the effective spectral efficiency (SE) based approach which takes into account the feature of multihop transmission. We compared these three schemes through system level simulation, which is based on 3GPP LTE system enhanced with 2-hop fixed relay nodes. The results confirm that the SE based scheme outperforms the other two schemes. Moreover, the results show that the effect of route selection heavily depends on the position of RNs. The REC system with signal power or SINR based route selection scheme yields even worse throughput than the non-relay case at certain positions. However, the SE-based scheme can always guarantee the gain from relaying.