Low-frequency Analysis of multiconductor transmission lines for crosstalk design rules

For early risk assessment in the design of cabling in an aircraft, as well as cable bundle optimization, efficient crosstalk estimations, and dependency of crosstalk with respect to designable parameters are required. A low-frequency technique for analyzing crosstalk in multiconductor transmission lines is presented. The result of this analysis is a closed-form expression for crosstalk in a specific cabling configuration. The technique has been validated via measurements and is used in two examples comprising two wire pairs close to a ground plane and in free space. Low-frequency closed-form expressions for near-end crosstalk are derived for both situations, which directly relate any designable parameter to crosstalk levels. Moreover, these expressions clearly show differences between the cases with and without a ground plane. Specifically, with the ground plane, the decrease in crosstalk when doubling the separation distance is 24 dB for pairs close to the ground, while it is 12 dB in free space. The closed-form expressions are utilized to create an overview of sensitivities of crosstalk to all designable parameters for both configurations. Finally, the low-frequency approximations of the chain parameters are applied to more complex nonuniform transmission lines, yielding more than 20 times faster computations when compared with complete MTL simulations

Performances of conformal and planar arrays

Static and dynamic deformations can have a severe impact on the performance of conformal antennas on aircrafts and other vehicles. Therefore it is essential to study the different deformation and vibration mechanisms and their influence on the antenna's radiation pattern. This presentation gives an overview of different approaches concerning electromagnetic modelling of array antennas and investigations on antenna deformations presented in the scope of TG20

Architectures for ku-band broadband airborne satellite communication antennas

This paper describes different architectures for a broadband antenna for satellite communication on aircraft. The antenna is a steerable (conformal) phased array antenna in Ku-band (receive-only). First the requirements for such a system are addressed. Subsequently a number of potential architectures are discussed in detail: a) an architecture with only optical true time delays, b) an architecture with optical phase shifters and optical true time delays and c) an architecture with optical true time delays and RF phase\ud shifters (or RF true time delays). The last two architectures use sub-arrays to reduce complexity of the antenna system. The advantages and disadvantages of the different architectures are evaluated and an optimal architecture is selected

Multiple grid methods for equations of the second kind with applications in fluid mechanics

SIGLEBSE B210350M / UCL - Université Catholique de LouvainBEBelgiu

Multifunctional Structures to Reduce the Energy Consumption of Future Aircraft with Integrated Ku-Band Antennas

The CO2 and NOX emissions of international air traffic must be reduced, making aviation more sustainable, requiring innovative technologies that reduce aircraft fuel consumption. The Horizon 2020 ACASIAS project takes up this challenge by improving aerodynamic performance and facilitating fuel-efficient engines such as Counter-Rotating Open Rotors (CROR). ACASIAS improves the aerodynamics through the conformal and structural integration of antennas into innovative aerostructures. Nowadays, installed aircraft antennas are protruding structures that generate turbulence and aerodynamic drag, thus increasing the fuel consumption, i.e. currently available Ku-band satellite antennas still require exterior installation on the fuselage. Hence, the conformal flush integration of a Kuband SATCOM antenna will reduce the drag, as well as CO2 and NOX emissions. Furthermore, ACASIAS will also reduce maintenance costs and minimise operational delays through structurally integrated antennas, reducing the risk of damage to protruding antennas

Towards structural integration of airborne Ku-band SatCom antenna

The paper describes research towards a fully structurally integrated Ku-band SatCom antenna. This antenna covers the complete receive band for aeronautical earth stations and DVB-S broadcast in Ku band (10.7 - 12.75 GHz). The antenna front-end consists of 32 tiles where each tile has 8×8 Ku-band stacked patch antenna elements. Optical True Time Delays (TTDs) in an Optical Beam Forming Network (OBFN) enable a squint free beam steering over the whole band to geostationary satellites. The Ku-band antenna itself covers the whole frequency band in input impedance matching and radiation pattern. The performance of a Ku-band antenna tile will be discussed. A design is presented for the structural integration of 32 tiles and the associated optical beam forming networks into a fuselage panel of an aircraft