Energy Harvesting - Wireless Sensor Networks for Indoors Applications Using IEEE 802.11

AbstractThe paper investigates the feasibility of using IEEE 802.11 in energy harvesting low-power sensing applications. The investigation is based on a prototype carbon dioxide sensor node that is powered by artificial indoors light. The wireless communication module of the sensor node is based on the RTX4100 module. RTX4100 incorporates a wireless protocol that duty-cycles the radio while being compatible with IEEE 802.11 access points. The presented experiments demonstrate sustainable operation but indicate a trade-off between the benefits of using IEEE 802.11 in energy harvesting applications and the energy-efficiency of the system

Wake-up radio systems for cooperative-intelligent transport systems architecture

© 2019 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes,creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.Cooperative-Intelligent Transport systems are new applications developed on top of communications between vehicles and between vehicles and fixed infrastructure. Their architecture envisages devices deployed along the routes and streets, transmitting and receiving different kind of messages belonging to different services. Quite often, these devices will be located in isolated places with very low number of vehicles passing nearby. Being in isolated places, these devices will require to be feed with rechargeable batteries and alternative power sources, the usage of which need to be very efficient. The fact of continuously transmitting messages whenever there is no vehicle to receive them demands a solution. In this paper, we propose to use a well-known saving power strategy already used in Internet of Things, the Wake-up Radio systems. As vehicular communications are based on IEEE 802.11 standard, we propose to use a Wake-up Radio system based on this standard as well, being thus no additional hardware needed for the wake-up transmitter. The paper analyses the feasibility of using this solution on several vehicular applications.Peer ReviewedPostprint (author's final draft

Technologies and solutions for location-based services in smart cities: past, present, and future

Location-based services (LBS) in smart cities have drastically altered the way cities operate, giving a new dimension to the life of citizens. LBS rely on location of a device, where proximity estimation remains at its core. The applications of LBS range from social networking and marketing to vehicle-toeverything communications. In many of these applications, there is an increasing need and trend to learn the physical distance between nearby devices. This paper elaborates upon the current needs of proximity estimation in LBS and compares them against the available Localization and Proximity (LP) finding technologies (LP technologies in short). These technologies are compared for their accuracies and performance based on various different parameters, including latency, energy consumption, security, complexity, and throughput. Hereafter, a classification of these technologies, based on various different smart city applications, is presented. Finally, we discuss some emerging LP technologies that enable proximity estimation in LBS and present some future research areas

Analysis of Energy Efficiency in IEEE 802.11ah

Recently, machine to machine (M2M) communication has been considerably evolved and occupied a large proportion of the wireless markets. The distinct feature of M2M applications brings new challenges to the design of the wireless systems. In order to increase the competence for M2M markets, several enhancements have been proposed accordingly in different wireless technologies. The thesis introduces these M2M enhancements with a focus on the Wi-Fi solution - 802.11ah technology. 802.11ah is a new amendment of Wi-Fi technology for M2M applications. In 802.11ah, a new mechanism named TIM segmentation has been introduced to provide scalable operation for a large number of devices as well as reduce the energy consumption. The scope of the thesis is to evaluate the energy efficiency of TIM segmentation in uplink traffic assuming Poisson process. To thoughtfully understand the principle of this mechanism, the fundamental MAC layer functions in Wi-Fi technologies have also been introduced. In addition, the thesis also proposed an energy-saving solution called additional sleeping (AS) cycles. The performance evaluation is based on a Matlab system-level simulator. The simulations are carried out for various TIM segmentation deployments for a selected M2M use case, the agriculture scenario. The results show that the TIM segmentation can deteriorate the performance for uplink transmission. This is because that in sporadic traffic, restricting the uplink access causes the increase in packet buffering and these packets leads to simultaneous transmission. This can be a serious issue especially for the network with a large number of devices. The random backoff procedure in Wi-Fi cannot efficiently solve this collision problem. In addition, results shows that the AS cycles can reduce the energy consumption in busy-channel sensing and also decrease the collision probability by adding extra randomness

A Review on Wireless Home Automation Systems based on Zigbee Technology

Development in wireless home automation has resulted in enriching the consumer experience in very simple manner. Home automation is one of the major application areas of ZigBee wireless networking. This paper reviews ZigBee Technology and its application in Wireless Home Automation Systems and compares it with other major existing technologies in implementing WHAS. The paper also lists some future opportunities and the challenges that ZigBee holds in this field

Energy Management in RFID-Sensor Networks: Taxonomy and Challenges

Ubiquitous Computing is foreseen to play an important role for data production and network connectivity in the coming decades. The Internet of Things (IoT) research which has the capability to encapsulate identification potential and sensing capabilities, strives towards the objective of developing seamless, interoperable and securely integrated systems which can be achieved by connecting the Internet with computing devices. This gives way for the evolution of wireless energy harvesting and power transmission using computing devices. Radio Frequency (RF) based Energy Management (EM) has become the backbone for providing energy to wireless integrated systems. The two main techniques for EM in RFID Sensor Networks (RSN) are Energy Harvesting (EH) and Energy Transfer (ET). These techniques enable the dynamic energy level maintenance and optimisation as well as ensuring reliable communication which adheres to the goal of increased network performance and lifetime. In this paper, we present an overview of RSN, its types of integration and relative applications. We then provide the state-of-the-art EM techniques and strategies for RSN from August 2009 till date, thereby reviewing the existing EH and ET mechanisms designed for RSN. The taxonomy on various challenges for EM in RSN has also been articulated for open research directives