An effective grouping scheme for avoiding hidden node problem in IEEE 802.15.4-based wireless sensor networks

Abstract

IEEE 802.15.4 standard is designed to achieve low-power transmissions in low-rate and short-distance wireless personal area networks (WPANs). For power consumption consideration, IEEE 802.15.4 uses the modified CSMA/CA protocol and does not have the hidden node protection mechanism, such as RTS/CTS mechanism. Previous studies indicated that the probability of any two nodes in an infrastructure network unheard of each other is around 41%. Therefore, the hidden node problem (HNP) results in inefficient data transmission and serious power consumption issues in WPAN. In this paper, we propose an efficient scheme to avoid the HNP. The idea is to perform hidden node relationship collection for all nodes and then allocate the hidden nodes into different groups with mutually non-overlapping schedules to transmit their frames. The proposed scheme partitions the time of a superframe into several subperiods, and the length of subperiod depends on the number of hidden nodes in a group. Simulation results demonstrate that the proposed scheme not only avoids the HNP but also outperforms the performance of IEEE 802.15.4 standard.