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A very compact coplanar waveguide (CPW)-fed ultra-wide band (UWB) printed antenna (PMA) is presented. The proposed antenna is supposed to cover the UWB range from 7 GHz to 10 GHz, with return loss values below −10 dB in the whole frequency range, for X-band applications, often used for dense satellite communications. The 30 $\pmb{\mathrm{x}\ 35\ \mathrm{x}\ 1.6\ \mathrm{mm}^{3}}$ antenna is mounted on a dielectric substrate named FR-4 with thickness $\pmb{\mathrm{h}=1.6}\mathbf{mm}$ , relative permittivity $\varepsilon \mathrm{r}=4.3$ and loss tangent of 0.025. All the design and simulated results are performed using CST Microwave Studio, 3D Electromagnetic Simulator software. The results show broad bandwidth and good omnidirectional radiation patterns in the passband, with a very compact size. The satisfactory overall performance with such a simple structure and small size makes the proposed antenna attractive for use in ultra-wide band (UWB) systems, especially for X-band applications.

A new ultra-wideband (UWB) antenna is presented in this paper. The proposed antenna shows the UWB operation in the frequency range of (3 GHz–13.5 GHz) with (S11

A new microstrip patch antenna for ultra-wideband applications is presented in this paper. The design and performance of the antenna component are discussed. The propounded antenna is mounted on a compact FR-4 substrate having dimensions 20 x 30 x 1.6 mm3 with relative permittivity εr=4.3. The rectangular patch antenna is slotted with two types; rectangular and semi-circle slots so as to ensure a broad bandwidth. The results reveal that the antenna covers the frequency range of 3.1–7.5 GHz with a reflection coefficient reduced to -55 dB and a maximum gain of 5.9 dB. The details of the simulated and measured results for reflection coefficient are presented, showing a good agreement between them. To analyze the effect of the slots, the surface current distribution is investigated. The performances of good impedance matching are achieved within the operating band. Simulations are performed using CST Microwave Studio. The propounded antenna can be deployed for UWB applications and other radio communication services systems such as high-resolution radar, military communication, communications and sensors, position location and tracking

Ultra-Wideband Printed Antennas Design

Electrical Power Systems should be designed in order to minimize the effects of system disturbances and to enable decision-making based on different configurations and relevant priority analysis. Automatic Under Frequency Load Shedding is a known effective solution to the problem of contingencies in the electrical power grid and it is the last resource to mitigate the damage caused by severe and unexpected contingencies. However, to the best of our knowledge, the load priority configuration, which have been presented so far in load shedding process do not take into account some important aspects, such as social, economic or political importance of the connected loads, as well as how negative is the impact on the public image of power utilities when disconnecting specific load branches. This paper aims to provide a general priority holistic function which can be applied to different load shedding schemes, independent of the adopted philosophy and operating principles. The proposed ranking is developed using a Fuzzy system for load priority classification that takes several aspects into consideration. To illustrate the method, an electrical power system was simulated, comparing a traditional load shedding scheme with two different sets of load priorities and evaluated by the proposed metric.

Buildings represent a significant portion of global energy consumption. Ventilation units are one of the largest components in buildings systems and are responsible for large part of energy consumption. Ventilation units are complex components, often customized for the specific building. Their faults impact buildings' energy efficiency and occupancy comfort. In order to ensure their correct operation, proper Fault Detection and Diagnostics methods must be applied. Hardware redundancy, an effective approach to detect faults, leads to increased costs and space requirements. We propose to exploit physical relations inside the unit to create virtual sensors from other sensors' readings, introducing redundancy in the system. We create linear regression models for three sensors using other sensors related through physical laws as inputs. We use two different measures to detect when a virtual sensor deviates from the actual one: coefficient of determination and acceptable range. We test our method on a real building at the University of Southern Denmark. Our method detects a fault in temperature sensor, where its readings have an abnormal trend and fall outside acceptable ranae for one day.