Enhancing Bluetooth Low Energy with wake-up radios for IoT applications

Wake-up radios (WuRs) are usually designed as a secondary near-zero power radio receiver used to trigger the main radio when a new communication is started over the air. Despite the tight relation with the main radio functions, it is usually implemented with separate hardware, firmware, and it is far from being integrated in the most diffused standard wireless protocols for sensors networks and for the Internet of Things (IoT). In this work, we want to check in-deep the coexistence between the Bluetooth Low Energy (BLE), which is one of the most used low-power short-range wireless standards for mobile and wearable communication, and a wake-up facility implemented in the same band. We focus on the analysis of the limits, advantages and drawbacks of adding this interesting feature in the BLE standard, and we discuss about the improvements in terms of power saving and latency of the communication. We target IoT applications and scenarios with a high density of BLE devices, analyzing the standard protocol and how WuRs can enhance its performance. Two common communication schemes will help us to show the limits and to define a design methodology for the application. Simulation results will show the trade-offs of the communication performance and the difference from a normal usage of the BLE. Finally, considerations about the usability of BLE with WuRs and guidelines will be provided as concluding remarks.