Tutorial

Low power wireless technologies for connecting embedded sensors in the IoT: A journey from fundamentals to hands-on.

 

Organizers

This tutorial has been composed by a team. Several researchers will join to present and support the hands-on session. Responsible authors for SAS 2019 (click each name to view the author's bio sketch):

 

Ing. Gilles Callebaut

KU Leuven, Belgium

Ing. Stijn Crul

KU Leuven, Belgium

Dr. Ing. Geoffrey Ottoy

KU Leuven, Belgium

Abstract

Embedded sensors are enabling a wide range of emerging smart services in domains ranging from healthcare to smart homes and cities. They are waiting to be connected to the internet and rapidly becoming crucial components of a valuable Internet of Things (IoT).

The variety of wireless sensor system applications demands for appropriate wireless connectivity. Several new technologies and standards are popping up, fit for short or large range, and various data rate requirements. Dedicated networks are being deployed for Machine Type Communication.

This tutorial will bring a theoretical and practical initiation to wireless technologies tailored for connecting embedded sensors. It will explain fundamental concepts of wireless propagation, highlighting the challenges and opportunities to realize low power connections. Several actual technologies and standards for different categories of connections will be introduced. A few illustrative use cases will be presented. A hands-on session will allow the participants to experiment with EFM32 Happy Gecko developer boards, cooperating in small teams. In a final session a glance on future trends will be given. The tutorial will be concluded with an overview of interesting relevant resources and a discussion with the participants on the expectations for follow up beyond the tutorial.


Content

The tutorial will make the participants familiar with state of the art wireless communication systems to connect embedded sensors in the Internet of Things (IoT). The lectures will first explain the challenges related to providing low power and reliable wireless connections, adapted to the typical needs of embedded sensors. Fundamentals of wireless communication will be introduced to provide the basics for understanding the different technologies that are proposed for wireless IoT connections specifically. The variety of actual available and emerging systems will be presented, and they will be illustrated with typical relevant applications.

The lecturers will welcome questions and look forward to discussions with the group of participants, also in preparation of the tutorial and the follow up.

The following schedule of lectures is planned:

1. Introduction and LPWAN Overview (30)

It is raining IoT technologies – which is very good news! A variety of solutions exists and is emerging, with different characteristics to meet the requirements of many different applications and embedded sensors waiting to be connected to the internet. IoT developers and integrators are often overwhelmed by the amount of standards and technologies available for IoT. Appropriate use cases for the different connectivity options will be illustrated from an IoT perspective.

2. How to go really low power (30')

A sketch of the context and expectations on connecting embedded sensors in the IoT. The typical anatomy of a connected embedded system will be introduced, and the challenges associated to their design and operation.

Break

3. Low and lower - reducing power consumption of IoT nodes: a hands-on (1h45’)

In this hands-on session the attendees will experience the development of a wireless sensor node. More specifically, how low-power operation can be achieved by clever utilization of the available resources. Such design choices include: selecting the right wireless technology, duty-cycled operation, hardware acceleration, etc.

The participants will experiment with a custom LoRa-based sensor, built with a Semtec SX1272 Radio chip and an EFM32 Cortex M0 processor. The way operations are being performed on the node can be customized in the Silabs Simplicity Studio IDE. The effect of these changes on the energy consumption can be observed through the IDE’s built-in energy profiler.

In the end, the lecturers will have shown that the design of true low-power wireless sensors requires a thoughtful design. Both software and hardware need to work seamlessly together within the boundaries of a specific application.