The goal of this graduation project was to design a state-of-the-art central farm controller. The designed central farm controller distinguishes itself from prevailing controllers by including a subsystem (the optimisation unit) that contributes to an improvement in power transmission effciency, decrease in maintenance costs and an increase in system reliability/robustness. This thesis describes the design process of the optimisation unit and the verifcation of its feasibility. Originally, the plan was to test the design on a remote terminal unit (RTU), but unfortunately due to the current crisis, this was not possible. Therefore, the implementation and testing were carried out only in MATLAB. Tests were performed using a MATPOWER system model which has been derived from a real wind farm topology. The optimisation unit makes use of a meta-heuristic algorithm to solve an optimal reactive power flow dispatch optimisation problem. In this thesis, the feasibility of this optimisation unit is investigated. Furthermore, it is determined which devices should be controlled and of which the usage is optimised. This makes the treated optimisation problem a multiple objective optimisation. Lastly, the robustness is verified by extending the topology and testing the solutions of the optimisation unit.

In this work the portion of the incident field that can be received by an antenna is investigated: the observable field. This field can be characterized only relying on the volume allocated to the antenna and thus independently from the specific antenna. The observable field is composed by a single spherical wave that first converges in the origin and then diverges to infinity. The power associated to the converging wave is the available power for the considered antenna domain. Previously, an estimation of this spherical wave was obtained by truncating the spectral spherical modal series representation of the incident field. Here we provide a more applicable approximation of the observable field, by truncating a spatial integral representation of the incident field that is based on the use of equivalent ideal currents. Eventually, for the vast majority of antennas, the estimation of the available power that can be obtained by approximating the observable field via the ideal currents is more accurate that the estimation that would be obtained via the spectral modal expansion. The ideas are first set considering the case of single plane wave incidence. Eventually, the extension to multiple plane waves is immediate and rigorous.

In this thesis a Volumetric Method of Moments (V-MoM) is developed to analyse accurately, and ease the design of small size lens antennas, and to estimate the power emitted by warm bodies constituted by realistic materials, and having arbitrary geometries. hanks to the application of the volume equivalence theorem and the use of a structured mesh, this method can be used in a design loop efficiently, since different geometries can be simulated with the same evaluation of the projections, and the specific material arrangements are added at a negligible cost. Therefore, at every design iteration, differently from other integral equation methods, only the linear system has to be solved. Moreover, thanks to the use of a uniform sampling, a convolutional structure is obtained, implying that only a reduced number of projections are sufficient to characterize the entire matrix, reducing significantly the memory requirements, and allowing the solution of large scale systems. The linear system is then solved with an iterative solver, that, thanks to the convolutional properties, can be accelerated by fast matrix-vector products by using Fast Fourier Transform (FFT). The method is validated by studying the field scattered by a homogeneous and multilayer dielectric sphere, proving an accuracy within the discretization tolerance, and the capability of handling inhomogeneous structures. A Graphical User Interface (GUI) based on the presented method has been developed, with the aim of easing and assisting the user experience on the electromagnetic analysis. The GUI allows to simulate complex geometries combining elementary shapes, characterized by arbitrary materials, and excited by either plane waves or discrete ports. The solution can be post-processed in terms near-fields, far-fields, and network quantities. A representation in terms of impressed currents and incident voltage has been formulated to represent the incoherent radiometric sources in the V-MoM, used to analyse the power emitted by lossy semiconductors, characterized by a Drude’s dispersion for the conductivity. An experimental setup to verify the numerical and analytical model is then designed

A rigorous model based on classic electromagnetism to characterize the thermal radiation of real ohmic media is presented in this thesis. This model explains the available energy due to thermal agitation inside ohmic material based on Johnson's theory of thermal noise in electric circuits. The field is expanded in a finite number of modes (degrees of freedom per unit of volume), which are all independent and orthogonal from each other and are eigenvectors of Maxwell's Equations. The minimum distance for two eigenvectors to be independent is found as half of the real effective wavelength in the medium, based on which an analytical expression of the total energy available by thermal agitation in the finite volume is given. Integrating Poynting vectors of sources over the entire object volume, an analytical expression to estimate the total spectral power radiated out by a real ohmic material body is derived, which does not utilize Planck's law of black body radiation as an intermediary. Finally, a measurement campaign is proposed aiming at providing accurate measurements of the thermal radiation from silicon samples of small dimensions in the mm and sub-mm wave range.

WiECG aims to create a prototype device which enable ambulance personnel to perform a 12-lead ECG without wires connecting the patient to the monitor. The proposed solution consists of a transmitter and a receiver device. The transmitter transmits the measured signals, the receiver sends the measured signals to the monitor, which shows the measured signals. This thesis describes the design and implementation process for the hardware. This concerns the amplification and filtering of the signals produced by the heart of the patient as well as the reconstruction and attenuation at the output of the receiver module. These processes should be done for 9 signals. Furthermore, component selection, design decisions and the process of implementing this analog signal processing on a printed circuit board is described including the interfaces with the modules used by the other subgroups of this thesis. The prototype built during this project was able to filter the 9 signals and send it from transmitter to receiver while only adding 1.572 𝜇V RMS noise to the output ECG signal.

When symptoms of atrial fibrillation (AF), a common cardiac arrhythmia, are experienced, a Holter monitor or event recorder is used for official diagnosis. Apart from the fact that these devices are experienced as inconvenient, AF can already manifest damage in a pre-symptomatic phase. This thesis is aimed at developing a method for recording heart activity using a wearable device to permit convenient early detection of AF. For this, heart activity is measured continuously by means of photoplethysmography (PPG). A classification algorithm is used to detect AF episodes in the PPG recording. If the algorithm suspects AF, a limb lead I ECG recording is requested from the user. The ECG recording can be analyzed by a clinician for official diagnosis. The Maxim Integrated Max86150 chip is used for the implementation of PPG and ECG. Acceleration data is gathered by means of the Adafruit MMA8451 accelerometer to allow for detection of motion artefacts. These sensors and the data they retrieve are controlled and processed by the ARM Cortex-M7 microcontroller. From the results, PPG recordings have a higher quality when infrared light is used as compared to when red light is used. However, both types of recordings are of sufficient quality for monitoring the heart rate accurately when in stasis. Although complete functionality of the system could not be verified, the results are promising for future work.

Distributed feeding in photo-conducting antennas (PCAs) leads to simple optical designs, less prone to overheating, as well to terahertz (THz) antennas that can operate non-dispersively over wide bandwidths. However, the efficient analysis of pulsed PCAs was so far limited to architectures characterized by feeds small with respect to the THz wavelengths. In this thesis, an efficient and rigorous procedure for the time domain analysis of an infinitely long slot antenna printed on photo conductive material and excited by a distributed pulsed laser is presented. The procedure is electromagnetically rigorous, and relies on spectral representations of the fields in both the frequency and spatial domains.