Saab Automobile AB

About: Saab Automobile AB is a based out in . It is known for research contribution in the topics: Radar & Antenna (radio). The organization has 760 authors who have published 890 publications receiving 11811 citations.

A method for executing a gear change in a vehicle

Abstract: The present invention relates to a method for executing a gear change in a vehicle. Said vehicle comprises first and second vehicle propelling machines (101, 102) and a first input gear set (180) and a first output gear set (108), each gear set (180, 108) having two numerically different gear ratios, which gear sets (180, 108) are coupled in series, such that each gear set (180, 108) has one gear ratio engaged in order to propel said vehicle, wherein said first input gear set (180) operates on both of said vehicle propelling machines (101, 102) and said first output gear set (108) operates on said second vehicle propelling machine (102). The method comprises the steps of: - changing gear ratio in said first input gear set (180) in a numerically suitable direction, and - changing gear ratio in said first output gear set (108) in a numerically opposite direction in relation to said first input gear set (180).

Challenges in updating military safety-critical hardware

Abstract: Herein, we describe challenges and suggest solutions when upgrading military safety-critical hardware where RTCA/DO-254 was never applied but is required now and not only for application-specific integrated circuits (ASICs), programmable logic devices (PLDs), and complex commercial-off-the-shelf (COTS) but for all hardware. Several challenges relate to modification to previously developed hardware resulting from hardware or technology enhancements, or procurement difficulties.

A heuristic model for the transmission cross section of wire-mesh covered apertures

Abstract: A simple and low-cost solution for protecting sensitive equipment located behind an aperture in an enclosure, such as a ventilation or display panel, is to use a metallic wire-mesh to cover the aperture(s). At high frequencies, where the aperture transmission coefficient is close to one, the transmission properties depend almost exclusively on the wire-mesh properties. Analytic models for the transmission coefficient of periodic (infinite) wire-meshes can then be used to provide a good approximation of the transmission properties of the wire-mesh covered aperture. At lower frequencies, however, the situation is more complex, since the transmission properties depend also on the size and shape of the aperture. An analytic model for the transmission cross section of wire-mesh covered apertures is proposed in this paper. At low frequencies this is based on a combination of the transmission cross section of a single wire-mesh cell calculated using the magnetic polarizability and a power relation, derived from antenna theory, relating the power transmitted through an array of apertures to the power transmitted through a single aperture. At intermediate frequencies the model assumes a frequency dependence found heuristically through numerical simulations. The proposed model provides results in very good agreement with numerical results over a wide range of frequencies and wire-meshes.

Program for simulation of relay networks

Abstract: The program described here has been tried out in order to simulate a relay network with such a degree of complexity, that its function can not be satisfactorly surveyed with manual methods. Since the program has a separate part, which translates Boolean equations and conditions of time delay written symbolically into the machine language, the program has got greater range of application and can be used for simulation of all systems, which can be represented in that way.