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This paper presents the preliminary design and integration of a notch antenna in an aircraft winglet. The antenna covers bandwidth reserved for VHF air traffic control.

A new optimized winglet of a small aircraft is used to develop the solutions for structure, VHF antenna, systems as lights and lightning protection. The aerodynamic optimization has been based on the Design of Experiment and Response Surface method in order to find out the suitable shape of the winglet from the aerodynamic, structure and the basic operating frequency range for VHF radio communication points of view. The winglet’s structure has been designed based on the aerodynamic loads and took into account the appropriate technology. The improvement of the aerodynamic characteristics and handling qualities of the aircraft are discussed and the integration concepts and production moulds are presented.

HIRF transfer functions results are rarely available to the public. Generally, the data provided in applicable guidance material are used for estimation of internal HIRF environment in an air vehicle. An exemplary set of HIRF transfer functions for a small aircraft is presented here. Results for the aircraft (10.4-m wingspan and 8.3 m of length) are compared with regard to state of the art approaches applied for aircraft HIRF certification campaigns. This is done in appropriate frequency ranges and by the use of applicable test methods with regard to requirements in place. For all major types of contemporary test methods, results are generated by measurement and numerical computer modeling. Principles of outcomes are discussed and compared to current practice in place. This concerns the shapes of the transfer functions on one hand and the order of magnitudes of obtained levels on the other hand. The obtained results show significant deviations from generic transfer functions currently applied in aircraft industry. The coupling to the interior of the aircraft observed here was higher than indicated by the applicable generic transfer functions. Numerical computer modeling is used here to verify the obtained outcomes by principle.

This paper deals with a new electrotherapeutic method for use in physiatric treatment. The micro-pulse stimulation is based on the combination of three electrotherapeutic methods: burst therapy, high-voltage pulsed current therapy, and microelectrostimulation. Micro-pulse stimulation is special for its unusual configuration of pulse parameters; high-voltage electric pulses are safely used as a result of a cumulative effect of the subthreshold monophasic pulses with a very short duration. This combination of parameters should connect the advantages of used methods. This includes an analgesic effect without any obvious adaptation of the stimulated tissue and making the tissue penetration easier. As the micro-pulse stimulation was designed especially for the treatment of swelling and pain in animal therapy, the device is small, portable, battery-operated and easy to use.

In this paper, electromagnetic effects arising from high intensity radiated fields (HIRF) within realistic aircraft structures are investigated using the method of moments (MoM) and experimental tests. This study focuses on simulation-to-measurement correlation, where two potential error sources are investigated: Accuracy of the numerical techniques and the generation of numerical models. It is shown that the conventional mixed potential electric field integral equation may lead to inaccurate results regarding the field penetration through apertures. An alternative integral equation is introduced which splits the computational domain into an interior and an exterior domain, improving the results for aperture problems. To analyze the accuracy and the range of applicability for these integral equations, a generic aircraft structure is investigated, both numerically and experimentally. Thereby, various modeling aspects required for a meaningful simulation of aircraft are discussed. Following these observations, a real aircraft is analyzed in a broad frequency range from 10 kHz to 1 GHz. It is demonstrated that accurate numerical techniques are as important as modeling and appropriate simplification of the considered structures.

In the paper, we discuss the issue of the analysis of a lightning protection system (LPS) of a composite nose in case of a lightning stroke. The analysis is based on numerical outputs produced by two different computational methods (FIT, MoM). Computational methods were applied on a simplified composite nose model of the aircraft EV-55. The analysis of the model itself has been accomplished in two ways: with and without the composite skin. The differences of these two options are described through their dissimilar response to the defined excitation signal, the character of which fully corresponds to the standardized character of the lightning stroke of the type A.

Reasons for performing study: Electrotherapy is used in human medicine and successively also in veterinary practice, but relatively little is known about the mechanisms of action in detail.This study is focused on identifying the physiological effects of micro-pulse stimulation, a new method designed for equine electrotherapy, using the thermodynamic sensing. Objectives: To establish on the basis of measurement with the Thermo Dynamic Sensors, if the micro-pulse stimulation has any effect on blood circulation. Methods: Twenty horses participated in this study. Two miniature Thermo Dynamic Sensors (TDS), working on the principle of the balance energy equilibrium and special designed for the measurement on horses, were placed on both forelimbs and monitored the changes in thermal activity. Micro-pulse stimulation of specified parameters was applied for a defined time only on one limb and the other was just considered as a reference. The measured responses were statistically processed, compared and evaluated. Results: The measured data were processed by basic and multivariate statistical analysis (correlation, Wilcoxon test, multidimensional scaling, and cluster analysis) which identified a significant difference between signals from stimulated and reference limb. A considerable increase of thermal activity is evident in signals from stimulated limb during the applied micro-pulse stimulation. Conclusions: Based on the results, it seems the micro-pulse stimulation really has physiological effect consisting in an increased blood perfusion which is associated with the warming-up of the stimulated area and this is detectable by the thermodynamic sensor. Potential relevance: Comparison and statistical evaluation of the measured signals provided a more detailed view on the thermal changes within the stimulated area, which is significantly related to blood circulation in limbs, and also with the support of the reduction of edema which could be one of the practical applications of micro-pulse stimulation (also tested parallel to this study).

Time Domain (TD) and Frequency Domain (FD) simulations of aircraft internal electromagnetic environment were carried out using a digital mockup of a real small aircraft. Results are compared with the experimental High Intensity Radiated Fields (HIRF) certification test carried out in a semi-anechoic chamber

A methodology for virtual EMC tests - comprising pre-processing, EM simulation, and post-processing - is presented. An aircraft application serves as an example for solving large multi-scale problems in CST STUDIO SUITTE™. The EM problem of the aircraft was solved for up to 12 billion Degrees of Freedom (DOF) on CST's computing cluster.

This paper deals with new developed thick film sensor based on powerful thermodynamic method using the high resistance ratio-metric sensor, which is improving the accuracy of the temperature measurement. This solution minimizes usual problems as dependance of sensor's sensitivity from other factors as power supply instability, ambient temperature shift, humidity and pressure changes, effect of self heating, aging, etc.

In this paper, simulation of a small aircraft complex model with shielded composite parts is presented. The emphasis is put on the analysis of the internal electromagnetic environment and its alterations caused by exclusion of specific parts of the aircraft. From the knowledge about the influence of these parts the possible ways how to simplify the simulation model are concluded.

The paper is focused on numerical studies of electromagnetic properties of composite materials used for the construction of small airplanes. Discussions concentrate on the homogenization of composite layers with metal lattice and composite layers with metal lattice with a slot. The homogenization is aimed to reduce CPU-time demands of EMC computational models of electrically large airplanes. First, a methodology of creating a 3-dimensional numerical model of a composite material with metal lattice in CST Microwave Studio is proposed focusing on a sufficient accuracy of the model. Second, two different approaches to homogenizing the composite with metal lattice are discussed. The proposed approaches are evaluated and compared from the viewpoint of the efficiency, the accuracy, the convergence, and hardware requirements. The obtained field distribution is compared with the distribution computed for the original composite walls.

Simulation of large complex structures (e.g. aircraft) with significant shielding composite parts is presented in this paper. The emphasis is put on the simplicity of model description without loosing its information capability. The complicated structure of the composite is substituted by a homogenous dielectric layer with constant thickness instead of a fine metallic mesh on a laminate surface. The influence of replacing shielding composite parts by equivalents is investigated by observing the changes of the electric field distribution in the chosen areas. Moreover, the ways of describing this type of composites in simulation models is discussed.

Segmented thermodynamic sensor in temperature shift balance circuit as the power AC/DC transmitter and direct working sub-systems thermo interactivity in thermodynamic systems is described. This paper deals with new thick film sensor used for thermodynamic direct power AC/DC transmission and metering in active industrial systems. In previous papers the basic principle of thermodynamic sensor was introduced and its construction on alumina ceramic substrate with commercial thick film pastes was demonstrated. Generally this sensor has plenty of application possibilities in various areas of industry. Some final users especially from RF area are asking for galvanic isolated sensors independent to contiguous environment effects. Such applications can be realized by the bisected thermodynamic sensor probe. The basic principle of this solution is segmented thermodynamic sensor with the thermodynamic environment temperature shift between more active sensor sections to influence of ambient temperature compensation. The simulation model of segmented thermodynamic sensor as particular segment elements of thermodynamic system was simulated. Values obtained from simulation are compared and discussed with experimental results. There is a good conformity between calculated and measured values. Results obtained from simulations enables construction of new family of segmented thermodynamic sensor probes in balance circuitry models. These could be integrated into many industrial thermodynamic metering systems designed in standardized design environments. They can be used as technical solution in galvanic isolated power measuring systems in integral industrial designs of any complex thermodynamics systems. Namely power and heat distribution, overpower protection systems, thermal circuit breaking systems, HIRF detection systems, etc.