Saab AB

About: Saab AB is a company organization based out in Thun, Switzerland. It is known for research contribution in the topics: Antenna (radio) & Signal. The organization has 862 authors who have published 928 publications receiving 8807 citations. The organization is also known as: Saab AB & Svenska Aeroplan AB.

Evaluation of switching losses in magnetic amplifiers as an alternative to IGBT switching technologies

Abstract: In future more electric aircraft (MEA) applications increased requirements of power levels stress the importance of low losses in converters and switching elements. In this work the losses of transistor switches are analysed and compared with the losses in magnetic amplifiers (Magamp) where amorphous alloy properties allows design of competitive devices. More Electric Aircraft technology can take advantage of this to accomplish compact, robust and reliable systems with low losses. Magamps are already used in the power supply of the Electronic Flight Control System in the Swedish "Gripen" fighter-aircraft. This paper presents a comparison between Magamp technology and an alternative Insulated Gate Bi-polar Transistor (IGBT) design. The study is concentrated on the power losses in a proposed 10 kW converter with ± 270 VDC (540 VDC) regulated output, where the fundamental difference between the switching elements is that the magnetic switch handles AC and the IGBT handles DC. To allow comparison, the copper and magnetic losses in the magnetic switch of the magnetic amplifier are considered as equivalent to the switching and conduction losses in the IGBT. The comparison is based on the sum of losses in power converters comprising six switching elements.

Test activities in the continuous integration and delivery pipeline

Abstract: Based on 25 interviews with participants from four case study companies that develop large-scale software embedded systems, this paper presents the Test Activity Stakeholders (TAS) model. The TAS model shows how the continuous integration and delivery pipeline can be designed to include test activities that support four stakeholder interests: “Check changes,” “Secure stability,” “Measure progress,” and “Verify compliance.” The model is developed to show how each of the stakeholder interests are best supported by unit/component tests or system tests, by automated testing or manual testing and by tests executed in simulated environments or on real hardware. The TAS model may serve as a starting point for companies when evaluating and designing their continuous integration and delivery pipeline. The validation of the TAS model included twelve individuals from three case study companies. The validation showed that the TAS model is actionable and useful in practice, enabling the identification of stakeholders and showing where improvement efforts should be focused in order to support all stakeholder interests in the continuous integration and delivery pipeline.

Manufacturing method with sliding layer

Abstract: A method for producing an article of composite material comprising the steps of: providing a moulding tool of male type; placing one or several prepregs on the moulding tool, forming a fibre stack; placing a dry layer, e.g. fabric, externally on the fibre stack, forming a fibre stack having a dry surface; providing a moulding tool of female type; overturning or tilting the stack having a dry surface from the male tool to the female tool. The method may further comprise the step of arranging said dry fibre layer so that this comprises the edge of the fibre stack. The dry layer may be made of a metal net or other suitable metal structures, or be made of glass fibre fabric or another similar glass fibre structure, or a combination of glass fibre and metal. The fact that metal is an electrically conducting material and that glass fibre is an electrical isolator may be exploited, particularly when producing aircraft components.

STAP analysis using multi-channel airborne radar data from flight trials

Abstract: Flight trials have been performed within the NORA program in order to acquire multi-channel clutter data for different types of terrain, terrain scattered interference, and SAR data. The acquisition of clutter and terrain scattered interference has been made in order to prepare a database for future development of operational space-time adaptive processing (STAP) algorithms applicable to active electrically scanned antenna (AESA) systems employing multiple sub-aperture configurations. In this paper we show some preliminary results that illuminate the benefit of using all four dimensions of multi-channel radar data in a clutter rejection perspective. To illustrate the behavior of multi-channel clutter we employ spatial spectrum estimation methods such as Fourier and MUSIC. We also demonstrate post-Doppler STAP results for the air-to-air case. The results are very promising and indicate that multi-channel processing will indeed enhance the ability to detect targets obscured by clutter.

A system and method for tracking and guiding at least one object

Abstract: The object of the present invention is to provide an inventive guidance system for tracking and guiding at least one object, wherein said guidance system comprises a base station (1) including an optical imaging system (3) configured to determine the angular position vector of said at least one object (5, 15), an optical communication link for transmitting guidance control commands from said base station (1) to said at least one object (5, 15), and steering means provided on said at least one object {5, 15) for adjusting the direction of said at least one object (5, 15) in response to said guidance control commands. The invention also provides a corresponding guiding method.