الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
One of the solutions used for supplying low-power medical applications is the photovoltaic energy harvesting system (PEHS). In this thesis, the proposed PEHS is composed of a photovoltaic panel, a DC-DC boost converter, a fixed resistive load, and an analog control algorithm. This algorithm is designed based on the output load current. It is implemented using the multisim tool. This algorithm is simple, low cost, and low power consumption because it measures only the output current parameter and does not need multipliers. The power consumption of the proposed load is approximately 39.24 mW. Therefore, the expected working duration of the load is 20.9 hours under continuously operation of the light for 4 hours. Finally, the simulation results illustrate the transient characteristics of the proposed PV system.
In this thesis, an autonomous wearable sensor node is developed for long-term continuous healthcare monitoring. This node is used to monitor the body temperature and heart rate of a human through a mobile application. Thus, it includes a temperature sensor, a heart pulse sensor, a low-power microcontroller, and a Bluetooth low energy (BLE) module. The power supply of the node is a lithium-ion rechargeable battery, but this battery has a limited lifetime. Therefore, a photovoltaic energy harvesting system (PEHS) is proposed to prolong the battery lifetime of the sensor node. This PV energy harvesting system is practically tested outdoor under lighting intensity of 1000 W/m2. Experimentally, the overall power consumption of the node is 4.97 mW and its lifetime about 246 hours in active-sleep mode. The experimental results demonstrate long-term and sustainable operation for the sensor node.
In this thesis, a self-powered Internet of Things (IoT) wearable sensor node is proposed for healthcare monitoring. This node enables doctors of measuring the heart rate, blood oxygen saturation (SpO2), and body temperature. This node is based on NodeMCU board that includes a microcontroller with a Wi-Fi chip. A solar energy harvester is developed as power supply to provide a solution for prolonging the lifetime of the node. This harvester is designed of two flexible photovoltaic (PV) panels, a charging controller, and a lithium-ion battery. The harvester is practically tested outdoors under direct sunlight and partly cloudy conditions. Experimentally, the IoT wearable sensor node consumes an average power of 20.23 mW over one hour and the lifetime of the node is 28 hours in a wake-up-sleep mode.
In this thesis, a wearable medical sensor system is designed for long-term healthcare applications. This system is used for monitoring temperature, heartbeat, blood oxygen saturation (SpO2), and the acceleration of a human body in real-time. This system consists of a temperature sensor, a pulse oximeter sensor, an accelerometer sensor, a microcontroller unit (MCU), and a Bluetooth low energy (BLE) module. Batteries are needed for supplying energy to this sensor system, but batteries have a limited lifetime. Therefore, a photovoltaic-thermoelectric hybrid energy harvester is developed to power a wearable medical sensor system. This harvester provides sufficient energy and increases the lifetime of the sensor system. The proposed hybrid energy harvester is composed of a flexible photovoltaic (PV) panel, a thermoelectric generator (TEG) module, a DC-DC boost converter, and two super-capacitors. Experimentally, in active-sleep mode, the sensor system consumes an average power of 2.13 mW over one hour and works without the energy harvester for 46 hours.