Proposed Hybrid MAC Layer Design for Priority Application Usage in Wireless Sensor Network (WSN)

The design of Medium Access Control (MAC) layer in Wireless Sensor Network (WSN) is very important because it gives significant impact in network performance especially in term of energy consuming. Contention Access method which is Carrier Sense Multiple Access (CSMA) will encounter collision problem when more than one node want to access the network simultaneously. Meanwhile, the issue in slotted access which is Time Division Multiple Access (TDMA) is channel utilization when the usage of the slot is neglected and wasted in transmission network. In this paper, we propose a hybrid MAC that combines both strengths of CSMA and TDMA in one protocol while avoiding their weaknesses to improve the network performance. The simple and efficient transmission in CSMA method will be used in neighbor discovery (ND) and slot allocation (SA) process. For data transmission, non collision transmission method which is TDMA will be used and it will be changed to CSMA depending on the contention level of the channel. This proposed protocol is suitable for priority application usage where the important information will arrived at the destination in acceptable delay time.