This assignment was given by Nordic Semiconductor. In this project a radio frequency energy harvesting system able to harvest ambient power at 900 MHz (GSM) was simulated and designed. A Villard voltage multiplier, boost converter and power management circuit was implemented for the harvesting system. The intention was to implement a system which would give sufficient output power and voltage to supply a load (nRF52810) at all times. The nRF52810 is a power efficient multi protocol SoC made by Nordic Semiconductor. Since the power harvested by the antenna is of AC power, a recti er was needed. A Villard voltage multiplier was proposed as the most suitable application. It not only recti es the voltage, but the voltage doubles for every stage. A 2-stage Villard voltage multiplier was proposed with the advantage that in theory the output voltage should be four times higher in magnitude than the input voltage. There exists several other ways to boost a voltage, a voltage boost converter was combined with the Villard Voltage multiplier. According to calculations the boost converter should boost the voltage up to 2.3 V. Since the assumed power from the harvesting system may be lower than the power consumed by the load, a power managing circuit was also needed, which would avoid the load to drain the current from the storage element before the voltage level was sufficient. Different solutions for a power management circuit was proposed using different variations of MOSFETs. A real-life design was implemented, but the Villard voltage multiplier gave out a much lower e efficiency than expected from simulations. The output power of the VVM was too low to supply the load (nRF52810).

This Thesis „Emergency Button for Seniors“ is about suggestion of realization of system emergency signalization. The System consists of programmable digital watch with wireless interface and PC with software processing signals. Status signalization is created by phone message and figuration of dialog on monitor. There is used free software for realization. Operation system on PC is Linux (distribution Ubontu 11.04). For graphic transitional plane PC application is used cross-platform framework QT. For watch firmware is used C compiler MSP430-GCC, MSP debug v0,15 and firmware OpenChronos.

Made available in DSpace on 2016-03-15T19:37:54Z (GMT). No. of bitstreams: 1 Fernando Biazi Nascimento.pdf: 3885211 bytes, checksum: 52d266afc3ffddce2e0abc915e2471a1 (MD5) Previous issue date: 2014-10-23 / Fundo Mackenzie de Pesquisa / The present work consists of an implementation of time distribution protocol based on PTP disclosed in the IEC 61588:2009 / IEEE 1588-2008 standard to be used in low-power wireless devices. The distribution of time is important to determine the order of occurrence of events marked in distinct counts that can then be related. And the problems of lack of synchronicity are evident in circumstances ranging from the study of historical facts up to the investigation of intruders in modern equipments connected to the internet. The work included development of a completely new software for the microcontroller MSP430F2274TM using the CC2480TMnetwork controller. The implementation of the protocol considers one of the mechanisms described by the standard and remains very close to it, not fully conformant mainly because of lack of resources on the used device, but the expected behavior was kept. The devices synchronize the time between them and sintonize their time counting, in a way to reduce, as much as possible, the adjustments of further synchronizations. / O presente trabalho consiste em uma implementação de protocolo de distribuição de tempo baseado no PTP, definido na norma IEC 61588:2009/IEEE 1588-2008 a ser utilizado em dispositivos sem fio de baixo consumo de energia. A distribuição de tempo é importante para determinar a ordem de ocorrência de eventos marcados em contagens distintas que podem então ser relacionadas. E os problemas de falta de sincronia são evidentes em circunstâncias que vão de estudo de fatos históricos até a verificação de intrusos em equipamentos modernos conectados à internet. O trabalho contou com desenvolvimento de um software completamente novo para o micro-controlador MSP430F2274TM utilizando o controlador de rede CC2480TM. A implementação do protocolo considera um dos mecanismos apresentados pela norma e ficou muito próxima, não atendendo-a plenamente principalmente por falta de recursos no dispositivo utilizado, mas manteve o comportamento previsto. Os dispositivos sincronizam os tempos entre eles e sintonizam suas contagens de tempo, de forma a reduzir, tanto quanto possível, o ajuste de futuras sincronizações.