Bluetooth Low Energy (BLE) has been designed as a power efficient protocol for small portable and autonomous devices, showing its efficiency for connecting these devices with smartphones to periodically and frequently exchange data, like heart rate or notifications. Additionally, BLE is present in almost every smartphone, turning it into perfect ubiquitous remote control for smart homes, buildings or cities. Nevertheless, there is still room to improve BLE performance for typical IoT use cases where battery lifetime should reach several years. In this paper we propose an extension to a model for evaluating BLE performance, latency and energy consumption, in order to provide realistic results based on various scenario conditions. In addition, we propose a parameter optimization of the BLE Neighbor Discovery process, in order to obtain the best performance possible depending on the constraints of specific use cases. Our results on two typical IoT test-cases show that advertiser battery lifetime can be increased up to ≈ 89× (9.55 days to 2.32 years) for a first case, and ≈ 281× (9.55 months to 7.36 years) for a second case.

Bluetooth Low Energy (BLE) has shown higher energy efficiency and robustness than other well known Wireless Sensor Network (WSN) protocols, making it a strong candidate for implementation in IoT scenarios. In addition, BLE is in almost every smartphone, turning it into perfect ubiquitous remote controls for smart homes, buildings or cities. In this paper we propose new operating modes for BLE to provide a much wider applicability range covering asynchronous, aperiodic and very low frequency scenarios while extending lifetime, without modification of the existing BLE specification. In order to estimate battery lifetime, we propose a coin cell battery model. We show how to efficiently adapt the protocol for different IoT scenarios based on their requirements, thus extending battery lifetime as much as possible while guaranteeing acceptable latency. Our results on two typical test-cases show that by using an optimized configuration and appropriate operating mode based on scenario requirements, lifetime can be increased up to ≈ 2× (4.1 to 7.3 years) for a BLE master in a first case, and ≈ 58× (3.05 months to 14.82 years) for a BLE slave in a second case. This shows BLE compatibility with a vast amount of IoT-related use cases.