Design of a battery-free wireless sensor node

Abstract

AgradecimentosÉ verdade que o meu nomeé oúnico escrito na capa deste documento, mas isso não significa que eu tenha sido eu oúnico autor, e nem tão pouco que a lista de pessoas que contribuiram de uma forma ou de outra tenha sido propriamente pequena, e por isso, ao meu orientador, prof. .6MHz e a respectiva antena. Além de ser passivo, o sistema propostó e também programável, uma vez que o sensor integra um microcontrolador de uso geral, e inclui um conector de 50Ω e uma interface para depuração e expansão, composta por um total de 26 pinos. Em termos de performance prática, o sistema propostoé capaz de executar tarefas relacionadas com comunicação e processamento até um máximo de 4.1 metros de distância de uma antena transmissora a operar dentro das limitações impostas pelas entidades reguladoras locais, no que diz respeito a potência. KeywordsRF energy harvesting; electromagnetic energy harvesting; wireless sensor networks; RFID; backscatter modulation; RFID sensor networks; wireless passive sensor networks. AbstractWireless sensor networks are currently of primary importance in a multitude of applications, and therefore, it comes as no surprise that there are many types of sensor nodes as well. Yet, almost all of them operate on batteries that normally deplete long before the predicted life span of basically all the other hardware components. Not only that, the large size of the batteries is indeed actually preventing sensor nodes from becoming smaller. One way of overcoming the drawbacks related to batteries is to remove them and harvest all the necessary energy from electromagnetic waves being radiated by a nearby source. In this document, a wireless sensor node designed to harvest energy from radio waves at 866.6MHz and its antenna are proposed and described in detail. In addition to being passive, the proposed system is also programmable, given that the sensor node includes a general-purpose microcontroller, and features a 50Ω port, and an interface for debugging and expansion, comprised of a total of 26 pins. Lastly, with regards to practical performance, the proposed system is able to carry out communication and processing tasks at up to a distance of 4.1 meters away from a transmitter antenna radiating within the limits imposed by local regulatory entities, with respect to power.

Low‐power ultra‐wide band pulse generator based on a PIN diode

“…Fig. 4 Layout of the passive RFID tag (shown on a 1:1 scale) used to test the pulse generator, taken from [8] Fig. 5 Pulse generated by the proposed UWB pulse generator, in response to a high-to-low transition (1.8 V to 0) produced by the RFID tag Curve 1 corresponds to a distance of 1 m and curve 2 corresponds to a distance of 2.6 m…”

“…4 (see [8]). This tag converts RF energy at 866.6 MHz to DC using a multi-level charge pump and a low-dropout voltage regulator of 1.8 V (hence the 1.8 V used in the previous simulation).…”

“…In this test, the pulse generator was connected to the tag and the tag was programmed to trigger pulses at a rate of 1 per second. A dipole antenna (the same antenna used in [8]) was attached to the tag to harvest energy from a 2 W erp pure 866.6 MHz source placed nearby, in direct line of sight. Both the power source and the tag were always kept at a distance of ∼1 m to the floor and at least 1 m to all other obstacles.…”

Boosting the Efficiency: Unconventional Waveform Design for Efficient Wireless Power Transfer

“…The maximum PAPR value occurs when all of the tones are aligned with the 0º phase [13]- [17]. Having equally spaced tone frequencies i i 0 $Ṽ~= + h is also a necessary condition.…”

Low power 8051-MISA-based remote execution unit architecture for IoT and RFID applications

“…Hence, the energy management of the terminal node of the IoT is an important factor in extending the lifetime of the sensor network. Wireless passive sensor network (WPSN) is a system of battery-free sensor nodes remotely powered by an RF source Fernandes et al, 2011;Isik and Akan, 2009;Bereketli and Akan, 2009). WPSN is a cost efficient and non-disposable system that operates on the received incoming power and is based on the passive RFID concepts especially with regard to the energy harvesting techniques Nintanavongsa et al, 2012).…”