Abstract: This invention concerns a procedure for the elimination of interferences, such as pulses and linear chirps, in a radar unit of the FMCW type. According to the procedure, the useable signal in the form of a beat signal, is subjected to time-frequency division of the type STFT for division of the signal into narrow-band frequency bands. Interference is detected and eliminated in each frequency band, after which the time signal freed from interference and its Discrete Fourier Transform, DFT, are calculated from the time-frequency division in narrow-band frequency bands.

Abstract: The invention relates to a process for determining the relative velocity in the radial direction between two moving objects, using linear frequency modulation with continuous frequency sweeps. A problem in such processes lies in being clearly able. to determine the phase difference. According to the invention, a clear determination is realized by varying the period. length for successive frequency sweeps and using the difference in period length and corresponding phase change in determining the volocity.

Abstract: A method and device for testing the function of a radar. A diode (21) with variable radar radiation impedance is arranged in the beam path (23) inside the antenna unit (4, 6) of the car radar and is fed with alternating current for simulating a radar target at a distance from the antenna unit. The obtained target data for the simulated target are compared to the expected target data for testing the function.

Abstract: This invention concerns a repeater jamming transmitter (2), and a casing arrangement with repeater jamming transmitter. The repeater jamming transmitter (2) comprises transmitter antenna (7), receiver antenna (8) and electronics part (10) with amplifier and control circuits. In order to avoid self-oscillation caused by leakage between the transmitter antenna (7) and the receiver antenna (8) and to maintain the isolation a special connection arrangement (7,8,10) is included in the repeater jamming transmitter. By means of the connection arrangement the amplification of the repeater jamming transmitter can be increased without self-oscillation arising.

Abstract: A method of presenting a complete image on the retina of an observer, wherein the image is comprised of a large number of pixels located along mutually adjacent lines. The presentation is effected by deflecting a limited number of pixels shown on a display over the image-perceiving area of a retina, wherein these pixels represent consecutively all pixels in the image. According to the invention, the display shows the pixels in at least one band of a limited number of complete lines in the image. The lines in the band are generated parallel with one another and such that each line represents successively the pixels in all lines of the image or a part-image. The band is deflected as a unit over the image-perceiving area of the retina in time with the generation of the lines on the display. The invention also relates to a system for use when carrying out the method.

Abstract: An antenna device for emitting and/or receiving electromagnetic radiation, such as radar radiation in a car radar apparatus is provided. Sweeping is realized by means of a fixed feeder and a rotatable reflector. The reflector is driven by a drive motor and its motion is monitored by a tachometer. The drive motor and the tachometer are constituted by so-called flag motors which are mutually motionally coupled to each other by mechanical means.

Abstract: In a procedure for the elimination of interferences of short duration, such as pulses, in a radar unit of the FMCW type, the transmitted and received signals are combined to form a useable signal. According to the procedure, the contribution to the Fourier Transform of the interferences of short duration are filtered out of the Fourier Transform in the frequency domain by an FIR filter with complex coefficients. The procedure requires no additional signal processing between sampling and applying the Fourier Transform, gives very little widening of strong contrasts in the Fourier Transform and is fast and simple to implement in a signal processor.

Abstract: A procedure for the elimination of interferences of short duration, such as pulses, in a radar unit of the FMCW type where the transmitted and received signals are combined to form a useable signal is provided. According to the procedure, interferences in the useable signal are detected and eliminated in the time domain and the part of the useable signal with interference is reconstructed by extrapolation based on samples without interference. Thus, the occurrence of interferences is prevented in the complex Fourier Transform of the type that is generated by known methods of clipping the signal.

Abstract: A method and an apparatus for controlling a radar oscillator for use in the traffic field, in particular for a car radar, for generating a linear frequency sweep. A phase-locked linearization loop generates a linear frequency sweep controlling a phase-locked oscillator loop, which has a considerably broader bandwidth than the linearization loop.

Abstract: A sight including an infrared camera. A first admission aperture receives an incident image. The position of the first admission aperture is rotatable vertically and sideways. A mirror arrangement is rotatable about a common axis for derotation of the incident image. An output aperture is fixed with respect to the infrared camera. The incident image passes through the output aperture to the infrared camera.

Abstract: A method of presenting a complete image on a retina of an observer. The image is built-up of a large number of pixels located along mutually adjacent lines on the retina of the observer by utilizing at least one line on a display which is separated from the observer and which consecutively shows the pixels in all lines of the image to be built up and presented on the retina of the observer, by deflecting the line shown on the display over the whole of the image-perceiving surface of the retina utilizing a line deflection movement which is non-linear in time, and by compensating for image distortion caused by the non-linear deflection.

Abstract: An opto-mechanical deflector device is used for line displays and is worn by an observer. By use of the deflector device, the line presented by the line display on the observer's retina can be perceived as a two-dimensional image. The deflector device comprises, for each respective eye, a plurality of similar subsidiary deflectors which are spread out in a one-dimensional or two-dimensional matrix across a surface corresponding to the desired angle coverage for the respective eye. The subsidiary deflectors are provided in such a number that the lines which the line display presents can be seen unbroken, irrespective of the line of sight of the eye within the field of view of the deflector device.

Abstract: An antenna device used in a car radar system for emitting and/or receiving electromagnetic radiation, comprises a rotatable reflector; a feeder fixed relative to the antenna device and interacting with the reflector; a motor for driving the reflector; and a tachometer for monitoring the rotation of the reflector and for controlling the drive motor. The drive motor and the tachometer are constituted by flag motors, each having a rotor with flat coils and a stator including permanent magnets, the rotor being rotatable in a magnetic field created by permanent magnets and having the coil ends directed towards the permanent magnets, the rotors of the flag motors being rigidly, mechanically connected to each other.

Abstract: A method for determining the course of another vehicle in relation to one's own vehicle by measuring the position of the other vehicle in relation to one's own vehicle with a transmitter/receiver system, such as a radar system permits course determination both on straight and on bend segments. According to the method, the side location of the other vehicle and one's own vehicle is determined at a position where the other vehicle is level with one's own vehicle, by moving the front vehicle backwards in time and/or moving the rear vehicle forwards in time, on the basis of position measurements of the position of the other vehicle. The side location of the other vehicle is compared with the side location of one's own vehicle, by which a measure of the discrepancy between the course of the other vehicle and the course of one's own vehicle is obtained.

Abstract: A sight apparatus has a day-sight part, a night-sight part and a filter which quenches the visible light so that the night-sight part in the form of an IR sight can be used during the daytime as well. In order to improve use of the night-sight under daylight conditions the filter has characteristics which quench visible light having wavelengths outside the wavelengths of blue light and is arranged in the beam path for the incoming visible light.

Abstract: An optical device for measuring the angular position of electromagnetic radiation, such as laser light, incident on the device, includes a lens system defining an input surface for receiving the incident electromagnetic radiation and an output surface towards which the incident radiation within the optical field of vision of the device is deflected by the lens system, a plurality of light guides each having a first end facing and in direct physical and optical contact with the output surface of the lens system, the first ends of the light guides substantially covering the output surface of the lens system, a detector allocated to each respective light guide and connected to its second end, and a calculating unit for determining a present angular position, based on the signal values outputted by the detectors, by calculating ratio between difference signals and sum signals of signal values of the detectors and determining the angular position corresponding to this ratio.