Abstract: A method for measuring a frequency f=&ohgr;/2&pgr; of a sinusoidal signal V(t)=Asin(&ohgr;t+&agr;) with an essentially constant amplitude A. Measured values are registered in the form of the instantaneous level of the signal V(t), V(t−h) and V(t−2h)at three points of time separated by a predetermined measuring period h, which corresponds to a measurement frequency fs=1/h.

Abstract: The invention relates to a radar station placed on the surface of the earth, and to a radar system comprising at least two such radar stations. The signal-processing equipment of the radar stations is adapted, at each point of time, to calculate probabilities of target positions and radial target velocity in relation to each individual radar station, based on the signals emitted and received by this station. These calculated values are associated over time, giving cumulative probability measures for target positions and radial velocities in relation to each individual radar station. By providing a system of at least two radar stations, it is possible to calculate the position of a target by associating target positions, such as they are perceived by the different radar stations, with each other by an association of characteristic movements of the target. This is done without having to synchronize the stations.

Abstract: The present invention relates to a method of detecting and classifying objects using radar. The method means that a broadband radar signal comprising wavelengths that coincide with characteristic lengths of targets to be detected and classified is transmitted. Further, a returned echo signal is received and analysed, at which a signal analysis in a combined time-frequency domain is used, which comprises determining characteristic frequencies in the signal return and their mutual time relations. Finally, a comparison with the corresponding stored values of an analysis of possible targets is performed.

Abstract: An electrode having a contact surface with the electrolyte consisting of a number of carbon fibers (1), and a method for the manufacture of an electrode where a number of carbon fibers (1) are wound into a carbon fiber skein (2) whereupon the skein (2) is gathered together at a connection area and embedded to form a connecting stud (5), which is then treated so that the end surfaces (6) appear of all the carbon fibers gathered together in the connecting stud (5), after which the carbon fiber end surfaces (6) are connected to a signal conductor (8). And an antenna (12) comprising electrically connected electrodes where the contact surface of each electrode with the electrolyte consists of a number of carbon fibers (1).

Abstract: The invention concerns a spin-stabilized projectile provided with a metal band (4). The projectile comprises a projectile body divided into a front main portion (1) and a rear main portion (2). The main portions are joined at the stern part of the projectile by means of a joint (3). The band is soldered or brazed with its inner surface and front flank surface onto an essentially cylindrical surface (6) and a rearwardly directed annular flank surface (5) of a shoulder which is formed in the rear end of the front main portion and extends round the projectile and which preferably has a length which is the same as the width of the band.

Abstract: The invention relates to a method of preparing dinitramidic acid HN(NO.sub.2).sub.2 and salts thereof having the formula M.sup.+n (.sup.- N(NO.sub.2).sub.2).sub.n, wherein M is a metal cation or a nitrogen-containing cation and n=1-3. The dinitramide salt can be used as oxidiser in solid propellants. Dinitramidic acid is prepared by nitration of a compound selected from a group consisting of NH.sub.2 NO.sub.2, NH.sub.4 NH.sub.2 CO.sub.2 ; NH.sub.2 SO.sub.3 H, NH(SO.sub.3 H).sub.2, N(SO.sub.3 H).sub.3, and its salts with metal cations or organic cations, e.g. NH(SO.sub.3 NH.sub.4).sub.2, and other products formed when ammonia is reacted with sulphuric trioxide, with a common nitrating acid such as nitric acid/sulphuric acid or nitric acid/acetic anhydride. The invention also relates to a method of preparing dinitramide salt, comprising neutralisation of dinitramidic acid with a neutralising agent, e.g. ammonia, and recovery of the dinitramide salt from a mixture of salts formed in the neutralisation.

Abstract: The invention relates to a propellant charge comprising a compact propellant and a method for electrically initiating and controlling the burning of such a propellant charge. Electrothermal energy is supplied to the propellant charge by feeding electric current over electrically conductive surfaces (6, 7, 19) in the propellant, and that said supply is made to different parts or zones (15) of the propellant charge at different points of time during the burning.The invention specifically relates to a projectile propellant charge having a first end (9) facing the projectile (4) and a second end (10) facing the back (3) of the weapon. The electrothermal energy is then supplied to the propellant charge, beginning in the first end thereof and then successively to the second end thereof by feeding the current at each point of time over an axially restricted part (15) of the propellant charge.

Abstract: A periodically integrating analog-to-digital converter and a sensor device having such a converter. The analog-to-digital converter has a measured-value-to-pulse-amount converter, i.e., a sigma-delta converter of the first order that is reset to zero before each new period, and a digital counter for the number of feedback signals of known reference value in the measured-value-to-pulse-amount converter. This constitutes a rough measure of the input signal. The analog-to-digital converter also converts the residual value of the measured-value-to-pulse-amount converter at the end of the period to a digital value, and an adder which adds this value to the output signal from the digital counter, resulting in a more accurate measure of the input signal.

Abstract: The present invention relates to a resonator for at least two laser modes from an optically pumped laser medium, in which each laser mode is reflected between a highly-reflective mirror and an output mirror. The laser resonator feeds back and separates at least two longitudinal laser modes having a given stable frequency difference between the modes by the laser medium being adapted to emit the concerned number of laser modes which are arranged to pass a Fabry-Perot etalon at different angles.

Abstract: The concentration of oxygen clusters in silicon is determined with a spectrometer, for the infrared interval, by obtaining the absorption coefficients for one or more of the wave numbers 728.+-.1, 734.+-.1, 975.+-.1, 988.+-.1, 1000.+-.1, 1006.+-.1 and 1012.+-.1.sup.cm-1, using the standard method that is used to determine oxygen atoms in interstitial position and carbon atoms in substitutional position when the measurement is carried out at the wave number 1106 and 605 cm.sup.-1. The absorption measurements are taken at room temperature and are standardized with respect to the thickness of the sample. The measurements are multiplied with a known calibration constant, whereupon the respective absorption coefficient for the different measured wave numbers are a measure of the concentration of different configurations of the oxygen clusters.

Abstract: The invention relates to a method of destroying explosive substances in which the explosive substances are converted to a pumpable liquid or suspension which is not detonatable but combustible and which can be burned in conventional boilers intended for energy production. The explosive substance is dissolved or suspended in a combustible liquid which contains no available oxygen or only a small amount of available oxygen, preferably fuel oil, wherein the amount of liquid present is so large as to reduce the energy content of the mixture to 1 MJ/kg or less in the absence of available atmospheric oxygen. The mixture is burned in a combustion apparatus, by delivering the mixture to the combustion apparatus via a liquid fuel burner or a burner for solid fuel/liquid fuel suspensions. The grain size of the explosive substance in suspension is selected so that each grain will be incinerated during its residence time in the flame of the burner concerned.

Abstract: A laser warning device for registering laser radiation from e.g. laser range finders or laser designators and providing a warning signal to make clear to the illuminated person that laser illumination has occurred or continues and establish the direction of incidence. A position sensitive detector or a position sensitive detector arrangement includes a detector surface that is protected from radiation that falls directly onto it, and a reflector. The reflector is designed to reflect towards the detector surface, while focusing towards the line of intersection between the detector surface and a plane that is perpendicular to the surface and in which the direction of incidence for the incoming radiation lies, the radiation that falls on the laser warning device and is parallel to the plane of the detector surface. The latter is defined as diverging not more than .+-.30.degree. from the plane. Further, the radiation may come from an arbitrary angle within the detector plane, up to 360.degree..

Abstract: With the intention of achieving more stable combustion in solid-fuel ramjets, and particularly in the case of ramjets with spinning application, it is proposed that the inner surface of the ramjet fuel element (8) is provided with raised surfaces, or lands (14), preferably formed from the fuel element material. In one preferred embodiment, the lands (14) are straight and extend parallel with the longitudinal axis of the fuel element and have the same length as the fuel element. The tangenital component of the rotating gasflow generated by rotation, forces the peripheral part of the gasflow to pass over these raised surfaces (14), thereby generating standing, stabilizing vortices downstream of the raised surfaces.

Abstract: One embodiment that is shown relates to a reconnaissance and/or weapons system for underwater use and comprises a vehicle 1, which may be a torpedo, and a support 2. The support is connected with torpedo 1 with a control wire 3. The wire has a density lower than that of water and will therefore float. The control wire is stored in a magazine and supported by buoyant means 4.

Abstract: The present invention relates to a method and a device for the detection of vessel dilatation components. The invention particularly relates to the detection of explosives, such as trinitrotoluene (TNT) and nitroglycerin. A biological detector is used, and precontracted blood vessels or parts thereof function as sensor elements.

Abstract: The invention relates to a weapon whose main object is to attack targets, such as armoured tanks, from above unexpectedly. The weapon includes an active part (1), a propulsion unit, such as a launching device (2), an anchorage attachment (4) which is intended to be firmly anchored in relation to the terrain, and a line (3) whose first end (5) is attached to the active part (1) and whose second end (6) is pivotally attached to the anchorage attachment (4). When used, the active part (1) is launched vertically upwards, with the line (3) held taut, whereafter the active part is guided by the line through the air in a circular arcuate path or trajectory (8) to a target (7), with the centre of the arcuate trajectory in the anchorage attachment (4).

Abstract: A countermass for a recoilless weapon which is intended to be placed behind the propellant charge of the weapon projectile and intended to depart together with the propellant gases that exit from the rearward end of the weapon when the projectile is projected forward. The countermass includes a plurality of mutually sequential and separated countermass bodies, each of which has a gas throughflow passage. The throughflow passage in the countermass bodies is sized to have a larger inlet area in bodies at the forward end of the countermass and gradually smaller inlet area in bodies at the rearward end of the countermass.

Abstract: A countermass for recoilless weapons which is intended to be placed behind the projectile propelling charge (3) of the weapon and which is also intended to depart together with the propellant gases exiting rearwardly from the weapon when the projectile is propelled forwards. The countermass includes a countermass body (5) which is deformable at the pressure and the temperature prevailing in the barrel during firing of the projectile and which has at least one gas through flow passage (6) which widens rearwardly in nozzle form.

Abstract: The present invention relates to a method to measure the angle of incidence for radiation and a detector to carry out the method. The background for the invention is that in certain electromagnetic radiation, for example laser light of different wavelengths from UV to IR, there occurs an irregularity, speckledness, that is among other things caused by turbulence in the atmosphere. This phenomenon gives rise to problems during the registration of a single or a few short pulses of radiation. Difficulties to reliably determine the angle to the source of radiation with high resolution can arise. This problem is solved by the invention by mounting two detector elements (1,2) so close to each other that both detector elements receive essentially the same irradiance and in such a direction that the normals of respective detector element form a known angle (.beta.) with each other. One then calculates the angle of incidence (.alpha.) by means of the signals (S.sub.1,S.sub.

Abstract: The present invention relates to a method to measure the angle of incidence for radiation and a detector to carry out the method. The background for the invention is that in certain electromagnetic radiation, for example laser light of different wavelengths from UV to IR, there occurs an irregularity, speckledness, that is among other things caused by turbulence in the atmosphere. This phenomenon gives rise to problems during the registration of a single or a few short pulses of radiation. The probability of detection can decrease considerably at the same time as difficulties to reliably determine the angle to the source of radiation with high resolution can arise.