Enabling ESP32-based IoT Applications in Building Automation Systems

Abstract

Low-cost system-on-a-chip (SoC) microcontrollers with integrated wireless network capabilities represent a constantly growing and reliable solution for interfacing industrial sensors and actuators commonly used in Building Automation Systems (BAS). These cheap and powerful devices are expediting the development of IoT applications and this process is even accelerated by the forthcoming roll-out of the 5G technology. However, built-in analog-to-digital (ADC) and digital-to-analog (DAC) converters are often characterized by low accuracy and non negligible gain and offset error that actually turn out to increase the final cost and complexity by requiring additional hardware.In this work, we analyze the requirements of a wireless interface for BAS and we discuss some key design considerations arising from the use of a ESP32 microcontroller. The scope of such adapter is to provide retrofit compatibility to the already installed devices, by supporting the migration to IoT platforms and by providing at the same time flexible 5G-ready capabilities. The performed analysis shows that the adoption of proper measures to compensate the errors of built-in converters, effectively enables the use of ESP32 in low-cost applications with industrial-grade performance.