Internet of Things (IoT) has been developing to become a free exchange of useful information between multiple real-world devices. Already spread all over the world in the most varied forms and applications, IoT devices need to overcome a series of challenges to respond to the new requirements and demands. The main focus of this manuscript is to establish good practices for the design of IoT devices (i.e., smart devices) with a focus on two main design challenges: power and connectivity. It groups IoT devices in passive, semi-passive, and active, giving details on multiple research topics. Backscatter communication, Wireless Power Transfer (WPT), Energy Harvesting (EH), chipless devices, Simultaneous Wireless Information and Power Transfer (SWIPT), and Wake-Up Radio (WUR) are some examples of the technologies that will be explored in this work.

Radon is a naturally occurring radioactive gas that can easily accumulate in indoor environments. According to the World Health Organization (WHO), radon gas is the second largest risk factor associated with lung cancer, after tobacco smoking. People spend at least half their life inside buildings, which are becoming increasingly more hermetic due to the pursuit of high energy efficiency – an increase in ventilation rates tends to increase heat losses. In this context, energy efficiency and Indoor Air Quality (IAQ) concepts, if not studied in a balanced way, can move in opposite directions. The introduction of Internet of Things (IoT) technologies for continuous assessment of the IAQ can help to achieve an optimally integrated balance between them. This article focus on the specification and design of the RnProbe, an IoT Edge Device developed under the scope of the RnMonitor R&D project whose main objective was the specification and development of a Cyber-Physical System (CPS) for integrated Radon Risk Management in public buildings, such as schools, kindergartens, offices, and hospitals, that are restricted to regular occupancy schedules, so that policymakers and building managers can reduce public health risks associated with the exposure to this pollutant. The device collects, aggregates, and transmits up to the cloud, several indoor environmental parameters. When combined these measurements are used to perform specific mitigation actions in the building, to improve IAQ.

The research of safety applications in vehicular networks has been a popular research topic in an effort to reduce the number of road victims. Advances on vehicular communications are facilitating information sharing through real time communications, critical for the development of driving assistance systems. However, the communication by itself is not enough to reach the most desired target as we need to know which safety-related information should be disseminated. In this work, we bring passive sensors and backscatter communication to the vehicular network world. The idea is to increase the driver (or vehicle) awareness regarding the presence of pedestrians in a crosswalk. Passive sensors and backscatter communication technologies are used for the pedestrians’ detection phase, while the vehicular network is used during the dissemination of the detection information to surrounding vehicles. The proposed solution was validated through end-to-end experimentation, with real hardware and in a real crosswalk with real pedestrians and vehicles, demonstrating its applicability.

In this work, three different concepts are used to develop a fully passive sensor that is capable of measuring different types of data. The sensor was supplied by Wireless Power Transmission (WPT). Communication between the sensor and reader is established by a backscatter, and to ensure minimum energy consumption, low power techniques are used. In a simplistic way, the process starts by the transmission of two different waves by the reader to the sensor, one of which is used in power transmission and the other of which is used to communicate. Once the sensor is powered, the monitoring process starts. From the monitoring state, results from after processing are used to modulate the incoming wave, which is the information that is sent back from the reader to the tag. This new combination of technologies enables the possibility of using sensors without any cables or batteries to operate 340 cm from the reader. The developed prototype measures acceleration and temperature. However, it is scalable. This system enables a new generation of passive Internet of Things (IoT) devices.

In the digital transition era of scaling down from macro through micro turbine; to the setting up of Smart Turbine Energy Harvesters (STEH), this paper presents Project Management (PM) principles applicable and best practices to meet the increasing energy demand of digitised technology. The massive deployment of autonomous devices such as those for Internet of Things (IoT), for the support of smart cities, has necessitated more research about their energy demands. With the use of ‘waterfall’ Project Management Methodology (PMM), turbine grid-connected energy are classified into different categories, and comparative study is made between scaling down of turbine grid from macro to micro, to the economic impact of setting up of STEH. This study concludes by proposing the use of STEH, which is an onsite green energy harvesting scheme that is self-sustaining; ubiquitous; and long lasting; as preferable source to other categories of turbine grid system. Additionally, it is an improvement on energy harvesting (EH) mechanisms using battery; whose replacement and disposal are not economical. STEH is considered economical and time saving with little or no physical and investment risk attached, the Return on Investment (RI) is considered favourable. Also, the energy delivery is sufficient for the requirement of IoT and Wireless Sensor Networks (WSN).

The use of wearable devices is increasing as a growing number of applications is introduced. The major limitation of these intelligent and multifunctional devices is the battery-charge capacity, which restricts the applications' scope.