Abstract— The IEEE 802.16 mesh mode supports two scheduling mechanisms, namely centralized scheduling and distributed scheduling. Centralized scheduling is based on a routing tree to offer centralized control. As we will show, the structure of the routing tree has a significant impact on the system performance. In this paper, we propose a routing tree construction scheme for centralized scheduling to fully exploit spatial reuse. Our proposed method can be seamlessly integrated into IEEE 802.16 without any modification to the protocol. In particular, our scheme takes into account both interference and bandwidth request during tree construction. Performance evaluation shows that the routing tree generated by the proposed scheme achieves performance close to the optimal result and significantly outperforms existing routing tree construction methods.