Performance evaluations of unslotted CSMA/CA algorithm at high data rate WSNs scenario

As a leading standard in wireless sensor networks, IEEE 802.15.4 based networks are well-adapted to various applications such as environment monitoring, building automation and medical/health care, in which sensor nodes are always densely deployed and with the intense channel competition. However, the use of 250Kbps low-rate based network that defined in the standard can be inefficiency for these applications. Therefore, in this paper with nRF24 transceiver that supports high data rate over the air transmission and reception, we analyse the packet loss and lifetime estimation of a high data rate network via SystemC simulations by using unslotted algorithm in 1Mbps and 2Mbps scenarios. The impact of macMinBE / macMaxBE (BE), macMaxCSMABackoffs(Backoff) and macMaxFrameRetries (Retries) are performed under different traffic loads and at 1Mbps and 2Mbps high rate along with 250Kbps low rate. Experimental results show that the use of greater BE under different traffic loads of three data rates,and smaller Backoff at high traffic loads under 250Kbps and 1Mbps are able to achieve better lifetime and less packet loss.For Retries, the use of a greater value under low traffic loads of 1Mbps and 2Mbps can provide a good trade-off between lifetime performance and packet loss. On the other hand, we also deepen the analysis to include the nRF24 transceiver´s embedded communication protocol engine Enhanced ShockBurst (ESB) for comparison. Furthermore, we also provide suggestions on the trade-off between packet loss and lifetime after each scenario analysis.