The globe is being challenged by growing population and accelerated urbanization, which demands sustainable usage and sharing of resources to create more livable and smarter environments at all scales. To answer those demands, the Internet of Things (IoT) is ultimately a powerful enabler to share resources on a large scale. IoT requires pervasive sensing, which demands a large number of distributed nodes with integrated circuits to collect information. Therefore, Photovoltaic Energy Harvesters (PVEH) have been widely chosen to power IoT nodes, which minimize the maintenance costs. PVEHs are usually managed by Power Management Integrated Circuits (PMIC), also referred to as Photovoltaic cell based PMIC (PV-PMIC). One of the most important feature of PV-PMIC is Maximum Power Point Tracking (MPPT), which ensures the system can output power at Maximum Power Point (MPP). Among various MPPT algorithms, Perturb and Observe (P\&O) is the most popular, which requires measurements of a combination of current and voltage of different nodes or branches, which are analog signals and need to be converted into digital signals. To achieve this analog-to-digital conversion, many ADC and TDC architectures have been proposed, but they are all challenged by power limitation and mismatch and Process, Voltage, and Temperature (PVT) variation. This thesis aims to present the design procedure of a new type of ADC for MPPT structure in a PV-PMIC system. To achieve the objectives, a literature research is carried out, with the research question being 'Which Analog-to-Digital Conversion techniques are suitable for MPPT in a low-power, small-area chip?'. After the literature research, a set of requirements is established and an alternative ADC design is proposed and tested. The proposed design combines capacitive current sampling and a Non-Linearity Canceling TDC. The proposed design is further verified at different levels, including the system level and the circuit level. The final verification includes three tests, namely the Linear Time Response, the Static Response, and the Frequency Response. The obtained results show that the proposed system at the circuit level achieves ENOB=3.97, FoM=4.17 pJ/conv-step, DNL bounded to +-0.8 LSB, and INL bounded to 2.5 LSB. It is further concluded that the proposed system generally meets the requirements. Moreover, the proposed system has unique advantages compared to conventional ADCs for the dedicated MPPT application. Possible future improvements include further improving linearities, designing calibration and trimming methods, and replacing the hard-coded logic with a storage component.

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In this thesis, the realization and qualification of an anechoic dome chamber for 5G antenna’s is discussed. As with audio, where no echoes or noise from outside is wanted when listening to music, when characterizing an antenna it must be prevented to get internal reflections or electromagnetic (EM) radiation from outside. For this reason, a measurement setup was simulated, using that setup, different absorbers were tested and characterized. And a Faraday cage shielding is designed and evaluated, to remove EM interference. To make the anechoic chamber physically possible, rebuilding the minidome was also required, so that the absorber and Faraday cage could be mounted on the inner wand of the dome. Eventually, a suitable test environment for 5G antenna’s is build. In the end, the assessment of the absorbing materials was completed, and the chamber achieved all requirements. Despite the space of improvement, the idea of building an anechoic chamber is successfully verified. ... Read more