Slotted ALOHA Based p-Persistent CSMA Energy-Efficient MAC Protocol for WSNs

Abstract

Extending the lifetime of wireless sensor networks (WSNs) is considered a vital challenge due to its limited sources, small size, and difficulty in replacing the battery when used to monitor remote areas. Various approaches and protocols have been proposed to reduce energy consumption. Medium Access Control (MAC) particularly random-access protocols are important techniques used to extend network lifetime and reduce energy consumption. In this paper, we proposed an improvement on the slotted ALOHA protocol using p-persistent carrier sense multiple access (CSMA) protocol. The channel divided into slots as in the slotted ALOHA, the distinction being that the slots have an adaptive duration based on the size of the data and do not impose the node to send at the beginning of the slot. In addition, the nodes sense the channel if it is idle or busy using the P-persistent CSMA approach before beginning the data transmission. The performance of pure ALOHA, slotted ALOHA, p-persistent CSMA, S-MAC, and T-MAC protocols was evaluated separately and compared to the proposed protocol. The simulation results show that the proposed protocol reducing energy consumption significantly hence increases the network lifetime.