Advances in microprocessor and wireless communication technologies have fostered the rapid development of large scale wireless ad hoc network. Some of these networks are composed of small sensor nodes which contribute to perform sensing tasks in different environments. In this paper, we explore the solution that is based on statistical information from nodes. In our Directional Optimal Energy-efficient Routing (DOER) protocol design, deviation angle, residual energy and hops to destination node are taken into account, the aim of DOER is to globally achieve energy savings in the whole network. Analysis result is provided to demonstrate the enhanced survivability of the network.