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.

Ethernet for avionics

Abstract: An avionics switched Ethernet network (1), for communication of data, the network comprising: a plurality of synchronized interconnected system nodes (N1-N3) each comprising: an avionics module (Al -A3) arranged to periodically provide a set of data messages, each comprising a set of data variables related to avionics functions, a network module (E1-E3) coupling the avionics module (Al -A3) to the network (1), said network module (E1-E3) comprising a network interface unit (15A- 15C) arranged to provide means for transmissions of data packets comprising a number of said set of data messages from said avionics module (Al -A3). According to the invention the network module (E1-E3) of each system node (N1-N3) comprise a transmission control unit arranged to control the network interface unit (15A- 15C) to perform scheduled transmissions of said data packets, wherein said transmission control unit is provided with access to memory means comprising scheduling information relating to a timing table comprising a plurality of time-slots (S1-S8) of predetermined duration within at least one periodically repeating communication time frame (125-128), wherein each of said plurality of time-slots (S1-S8) is statically allocated a predetermined number of data packets, each comprising a predetermined subset of data messages from said set of data messages.

Best quality given a maximum bit rate

Abstract: The present invention relates to flow control of a digital data stream that is to be transmitted with limited bit rate. The present invention provides a mix between CQ and CB. This in order to, in real time, ensure best possible quality of a data stream given a maximum available band with. This is useful both when saving a data stream to a data storage with a limited size and when playing the data stream in real time. In particular the invention relates to a method for flow control of a digital data stream that is to be sent with a limited transmission bit rate R. The method comprises encoding each data frame of a digital data stream into an encoded data frame comprising n quality layers and thereafter balancing the output of the encoder in order to achieve a constant bit rate on the output. The invention also relates to a corresponding data recorder and computer program.

Method and apparatus for phase compensation in a vehicle control system

Abstract: The present invention relates to a method and a device for executing phase compensation in a control system of a motor-driven vehicle, in which the time derivative for an output signal (y) from a circuit (1) contained in the control system is limited relative to the time derivative for an input signal (u) to the circuit (1) if the time derivative for the input signal (u) exceeds a predetermined value. A difference signal (e) is formed between the output signal (y) and a signal (x) present in the circuit (1), the time derivative of which is not limited in relation to the time derivative for the input signal (u). The difference signal (e) is filtered via an asymptotically stable filter (3) to form a signal (δ), which is fed back and added to the input signal (u) of the circuit (1) to form the signal (x). A conventional rate limiter may be used to form the output signal (y) from the signal (x).

Method for fabricating a curved beam from composite material

Abstract: A method for fabricating a curved beam from fiber composite material. A flat fiber composite laminate including a plurality of layers and at least two different fiber directions is formed. The fiber composite laminate is disposed in contact with a male tool includes a first flange, a second flange and an intermediate web. The male tool is curved in its longitudinal direction with a radius of curvature in such a way that the first flange has a shorter longitudinal extent than the second flange. The fiber composite laminate is brought into contact with and secured to the first flange of the male tool. The male tool and the fiber composite laminate are then rotated relative to one another so that the fiber composite laminate is brought into contact with the intermediate web of the male tool in a first rotational movement, and brought into contact with the second flange of the male tool in a second rotational movement. The fiber composite laminate hardens on the male tool, and the finished beam is separated from the tool. Also a beam of fiber composite material fabricated according to the method.

RFI suppression in SAR

Abstract: A filter scheme for broadcast interference cancellation that is computationally efficient and numerically robust Airborne Low Frequency Synthetic Aperture Radar (SAR) operating in the VHF and UHF bands has been shown. At least interference Doppler filtering or interference cancellation is utilised. The interference cancellation involves prediction of the interference for each particular reception interval of mixed interference and radar ground response. This prediction is then coherently subtracted from the incoming signal.