An efficient CSMA-CA algorithm for IEEE 802.15.4 Wireless Sensor Networks

Abstract

networks, the range of backoff exponent is limited to very small values. Problem arises with increased probability of devices choosing the same number of backoff period (BPs). In return, this problem affects the channel utilization and packet collisions. In this paper, we proposed an efficient and adaptive backoff algorithm (EBA) to minimize the collisions among the contending nodes. While CSMA-CA delays for a limited number of backoff ranges, EBA is designed to enhance the performance of CSMA-CA by choosing the appropriate window size based on the collisions determined by the node. Furthermore, to increase the efficiency of EBA we split the backoff period into sub-backoff period called temporary backoff (TB) and next temporary backoff (NTB). During the implementation of EBA, the node choose the TB and NTB value randomly which is represent 10% to 50% of the actual backoff delay value instead of choosing backoff exponent (BE) randomly as in the standard. In this case, we decrease the probability of choosing the same number of backoff exponent randomly selected by nodes and minimize the probability of collision. Hence, we give better opportunities for successful packet transmissions. Simulation results demonstrated and compared the performance of EBA with that of IEEE 802.15.4 standard. According to the results obtained, EBA achieved better performance than the 802.15.4 standard in terms of throughput, delivery ration, and power consumption.

Modified Adaptive Mechanism for Optimising IEEE 802.15.4 WPANs for Wireless Sensor Networks

“…To resolve the trade off and to reduce randomness, the DBA coordinator assigns different tailored back-off to different nodes competing for medium. The authors in [7] propose an e cient CSMA-CA algorithm EBA which modi es contention window size in accordance with the probability of collision parameter. This parameter depends on the number of nodes in network and divides the back-off periods for maximum utilisation.…”

Segmentized Clear Channel Assessment for IEEE 802.15.4 Networks

“…Previous research for enhancing CSMA/CA algorithms by adjusting CCA can be divided into two categories. The first category involves updating the number of CCAs adaptively, as shown in [ 7 , 8 ], etc. The efficient backoff algorithm (EBA) updates the number of CCAs based on the probability of collision parameter [ 7 ].…”

“…The first category involves updating the number of CCAs adaptively, as shown in [ 7 , 8 ], etc. The efficient backoff algorithm (EBA) updates the number of CCAs based on the probability of collision parameter [ 7 ]. The priority-based binary exponential backoff (PB-BEB) algorithm adjusts the number of CCAs by considering the fairness between devices [ 8 ].…”

Study on the energy consumption in wireless sensor networks

“…Xbee PRO radio module has built-in functions and protocols for Medium/Media Access Control (MAC) [124], [125], [128] in order to allow multiple modules to use the shared medium. The Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) [124], [125], [128]- [131], used in Xbee PRO modules, provides a reliable way to send and receive messages without major problems caused by collisions [132]- [135].…”