On Optimal Energy Efficiency in Low-Rate Wireless Personal Area Networks

Characterizing and optimizing energy efficiency in Carrier Sense Multiple Access (CSMA)-based Low-Rate Wireless Personal Area Networks (LR-WPANs) remains challenging due to varying power consumption levels and sporadic data transmission. To address this issue, this paper focuses on the analysis of energy efficiency in CSMA-based LR-WPANs. Specifically, by considering finite energy, varying power consumption, and network throughput, we derive the closed-form expressions for lifetime throughput and achieve optimal energy efficiency by tuning the access probability. The analysis indicates that when data traffic is sporadic, the optimal channel access probability aligns with the right endpoint of the unsaturated region. Maintaining the access probability at this optimal point significantly minimizes energy wastage, balances network throughput, and reduces contention. These findings provide valuable insights into the configuration of access parameters for achieving high energy efficiency in CSMA-based LR-WPANs.