Performance Evaluation of IEEE 802.15.4k Priority Channel Access with DSSS PHY

Low-energy critical infrastructure monitoring (LECIM) applications are rapidly increasing. A communication protocol developed to fulfill the LECIM requirements is the novel IEEE 802.15.4k standard. In this paper, we study the impact of priority channel access (PCA), a feature defined for high priority message transmissions in the IEEE 802.15.4k standard, in LECIM DSSS physical layer (PHY). An LECIM network that employs a Slotted Aloha (S-Aloha) with PCA channel access scheme in conjunction with non-saturated traffic conditions is presented in a varying propagation environment.

OPNET simulation results show that the application of a priority access in the network significantly improves the delay performance of high priority messages while imposing less effect on the overall network performance of low priority messages. However, the reliability performance of the PCA scheme is approximately the same as the reliability performance of a non-PCA scheme for high priority messages. Furthermore, in a last-gasp scenario, during which a large amount of high priority data traffic is observed in the network, an LECIM DSSS PHY with PCA system fails to yield the expected network performances.