Mobility Adaptive CSMA/CA MAC for Wireless Sensor Networks

In this paper we propose high throughput low collision, mobility adaptive and energy efficient medium access protocol (MAC) called Mobility Adaptive (MA-CSMA/CA) for wireless sensor networks. MA-CSMA/CA ensures that transmissions incur less collision, and allows nodes to undergo sleep mode whenever they are not transmitting or receiving. It uses contention based as well as contention free period efficiently together to minimise the number of collisions cause by the mobile node entering and leaving the clusters. It also allows nodes to determine when they can switch to sleep mode during operation. MA-CSMA/CA for mobile nodes provides fast association between the mobile node and the cluster coordinator. The performance of MA-CSMA/CA is evaluated through extensive simulation, analysis and compared with the existing IEEE 802.15.4 industrial standard. The results show that MA-CSMA/CA outperforms significantly the existing CSMA/CA protocol including throughput, latency and energy consumption.