Method for handling collisions of broadcast packets due to hidden node problem

Abstract

In this paper a method of collision detection and retransmission of broadcast packets is proposed. In multi-hop wireless networks, broadcasting is an elementary part of the routing process. However, due to the hidden node problem, broadcasting often leads to collisions. In the presence of broadcast collisions, a node cannot populate its neighbor table completely, leading to missing out on knowledge of potential neighbors. The proposed method uses Collision Detection Pulse (CDP) to make other nodes in the vicinity aware of a collision. If transmitter of the broadcast packet detects a CDP right after the completion of transmission, it retransmits the broadcast packet. The performance of the proposed method is compared with that of IEEE 802.11 DCF (Distributed Coordination Function) standard. Simulation studies show that the proposed method outperforms the existing IEEE 802.11 DCF in discovering the neighbors of a particular node. With the proposed method, every node can discover all its neighbors within a maximum delay of 161ms.