Abstract: In a fire control system for a vehicle or vessel a data processor (21) connected to the target tracking unit (7) determines, in a first coordinate system coupled to said unit (7), angular error data about a target position for aligning the tracking unit (7) with the target position.A fire control computer (22) is incorporated for:a. determining matrix (H) elements concerning the transformation from the first coordinate system to a second fixed horizontal coordinate system, using data about relative angular positions between the tracking unit (7), the vehicle or vessel and a turret mounted thereon, and using data from reference orientation means (18, 19, 20) about the angular positions in said second coordinate system;b. converting the angular error data into target positions in said second coordinate system;c. changing said target positions to gun aiming data; andd. transforming the latter data to a third coordinate system coupled to the vehicle or vessel.

Abstract: A pulse radar apparatus is provided with a first receiver (4) connected to a directional antenna (3) and a second receiver (13) connected to an omnidirectional antenna (12). The receivers (4, 13) are suitable for reception and processing of long-duration and short-duration radar signals respectively, whereby at least the long-duration signals are frequency-modulated and subjected to pulse compression. The radar apparatus is further provided with a side-lobe blanking circuit (20) and switching means (25, 26).

Abstract: A communication receiving unit for the suppression of noise and jamming signals, which receiving unit comprises:a plurality of antenna elements (1A-1N);adaptive weighting filters (7.sub.A,a, . . . , 7.sub.N,k+1) connected thereto;a combination circuit (4) connected to the weighting filters (7.sub.A,a, . . . , 7.sub.N,k+1);a detector (5) connected to the combination circuit (4) suited to generate a replica (d) of the information-supplying carrier signal for demodulating the signal (y) of the combination circuit (4) to the information-related frequency band; anda unit (8) for adjusting the weighting filters (7.sub.A,a, . . . , 7.sub.N,k+1).The detector (5) comprises a circuit (40, 41) for determining a time-averaged power value (W.sub.1) concerning the signal (y) from the combination circuit (4), and a circuit (42, 43) for determining a time-averaged value (W.sub.2) of the cross-correlation concerning the output signal (y) and the replica (d).

Abstract: A video extractor for a pulse radar apparatus comprises a memory capable of storing a number of words corresponding with the number of range quanta, into which the range interval of the pulse radar apparatus is divided. The rate at which words are shifted in and out of memory corresponds with the counting rate of the range counter of the pulse radar apparatus. A video processor updates the target information in the words in response to video, angular and range data from the pulse radar apparatus. The target information contains at least the initial azimuth value jb(r), the final azimuth value je(r), the weight E(r) and the target number N of a series of hits established in the range quantum r. A processor, receiving at least the above information from the video processor determines the center (MR, M.phi.), the direction .0., the length L, the width B and the weight E.sub.o of the target.

Abstract: Integrated weapon control system including target search and tracking means, whereby the turret is rotatable about an axis perpendicular to a first reference plane and whereby the gun is slewable about an axis parallel to this first reference plane. The target search means are fitted triaxially on the turret and stabilized biaxially with respect to a second reference plane, wherewith the target tracking means are mounted multi-axially on the gun.

Abstract: In a pulse radar apparatus the receiver comprises a main transmission channel connected to a directional antenna and an interference canceller connected to said channel for selecting target returns obtained through the major lobe of the antenna radiation pattern. The canceller contains an auxiliary transmission channel connected to an omnidirectional antenna for the intermediate-frequency detection of target returns and of signals composed of noise and/or continuous-wave interference signals; a subtraction unit; and a phase- and amplitude-compensating network having two circuit arrangements, one for the in-phase output signal and one for the quadrature output signal of the auxiliary transmission channel for generating output signals for the subtraction unit. Each circuit arrangement consists of a first mixer connected to the subtraction unit and the auxiliary transmission channel, a filter connected to the first mixer, and a second mixer connected to the filter and the auxiliary transmission channel.

Abstract: Sonar apparatus provided with a beamforming network (1) containing several receiving channels (4A-M) for supplying, for each direction of beam incidence, digital composite signal products obtained by superposition of the receiving channel output signals and for transforming the signal products to a low-frequency band. The signal products are fed to a signal analysing circuit (3) comprising blocking circuits (62 and 63), and to a noise detector (61) for deriving, for each direction of beam incidence, a blocking circuit control voltage from the interference signal components in the signal products. The noise detector selects signals outside the low-frequency band part representing the transmitting/receiving band, and determines the modulus of the filtered signals and the average value thereof. The modulus and, after thresholding, the average value are fed to a comparator (77) to generate the control voltage.

Abstract: Search radar apparatus containing an MTI video processing unit provided with: a canceller for generating video signals of moving targets; a zero-velocity filter for generating clutter video signals; a conditional circuit connected to the canceller and the filter for generating per range quant of each radar scan a clutter switching signal if for the rang quant the signal value obtained with filter is greater than the signal value obtained with the canceller; a combination circuit connected to said filter and the conditional circuit for selecting the clutter video signals present with the clutter switching signals and for determining therefrom a temporary clutter level in each clutter cell and each antenna revolution period; and clutter level indication means connected to the combination circuit for determining a standard clutter level per range-azimuth clutter cell of the radar range with the application of clutter video signals.

Abstract: A threshold circuit comprises a shift memory (1) supplied with sampled and digitized radar video data; two adder circuits (2, 3) connected to the first and the last elements of the shift memory (1); and a selection circuit (5) for passing the greater of the two output signals from the adder circuits (2, 3). The output signal of the selection circuit (5) represents a first threshold value for the radar video data from the center element of the shift memory (1). The threshold circuit further comprises a noise level detector (6) connected to the selection circuit (4). The output signal of noise level detector (6) represents a second threshold value for the radar data from the center element of the shift memory (1). A comparator (10) and a gate circuit (13) are used to obtain the radar video data from the shift memory (1), when the amplitude of the video data is in excess of the greater threshold value.

Abstract: In a pulse radar apparatus target returns are detected, sampled, digitized per range quant and frequency analyzed. The apparatus includes a cell classification unit (5) for deriving from the spectrum of the target returns a cell classification signal, whose logical values indicate whether the target returns within a radar cell are classified to be from a moving target or from a fixed target. In a microprocessor (15) the cells, which cluster, while a signal represenmtative of the target covered by the collectively cover one single target, are combined to form a cluster is determined. In the microprocessor (15) a cluster classification signal is derived, whose logical values indicate whether the target returns within the cluster are classified to be from a moving target or from a fixed target. The signal representative of the target covered by the cluster is read out if it is derived from target returns classified to be from moving targets.

Abstract: In a radar system frequency-modulated transmitter pulses of relatively long duration and frequency-modulated transmitter pulses of relatively short duration are generated and transmitted through a common transmitter channel, both channels containing a pulse compression filter, for the detection of return signals from the transmitter pulses of relatively long duration and of relatively short duration respectively.

Abstract: In a pulse radar apparatus target returns are detected, sampled, digitized per range quant and frequency analyzed. The apparatus includes a cell classification unit (5) for deriving from the spectrum range of the target returns a cell classification signal, whose logical values indicate that the target returns within a radar cell are classified, in the first instance, as first trip and multiple trip signals. In a microprocessor (12) the cells, which collectively cover one single target, are combined to form a cluster, while a signal representative of the target covered by the cluster is determined. Furthermore in the microprocessor (12) a cluster classification signal is derived, whose logical values indicate that the target returns within the cluster are classified as first trip and multiple trip signals. The signal representative of the target covered by the cluster is read out if it is derived from target returns classified as first trip echoes.

Abstract: A tension adjusting device for the oscillating guide tubes in a sliver felting machine comprises a lever mechanism with a first tension adjuster for exerting a tension simultaneously on a plurality of guide tubes. A second tension adjuster is included for exerting tension on the guide tubes individually.

Abstract: An energy converter comprising a series-resonant bridge circuit (1) tuned to a constant frequency. A number of parallel-connected output transformers (2, 3) are accommodated in the bridge circuit and energy buffers (6, 7) are coupled to the secondary winding of each of the output transformers. By means of control circuits (23, 24) activated by the voltage across the different energy buffers the current through the primary winding of a relevant output transformer is controlled so that the voltage across the corresponding energy buffer remains constant.

Abstract: A method and apparatus for reducing radar target data which must be processed by a data processor. The area covered by the radar is divided into a number of range-azimuth zones and a standard number of data to be processed for each zone is established. A target azimuth extent for each zone is continually adjusted to keep the number of data processed for each zone within the standard number for that zone.

Abstract: An energy converter comprising a series-resonant bridge circuit (1) containing at least two thyristors (6, 7), first and second respective diodes (8, 9) connected antiparallel thereto, a high-frequency output transformer (23), and an energy buffer (2). A control circuit (20) is incorporated for generating trigger pulses for the appropriate thyristors in response to the energy of the buffer (2). The energy converter comprises means for ensuring that the diode, antiparallel connected to the last-conducting thyristor, starts to draw current immediately after this thyristor is blocked. The control circuit also generates signals indicative of the presence of current flowing through the diodes (8, 9), which signals control the supply of the trigger pulses to the thyristors (6, 7).

Abstract: In a method for increasing the cover of textile fabrics yarns are used, at least part of which exhibit potential fiber-spreading properties, which can be activated by removing from said yarns, processed into a fabric, the adhesive used for the fiber bonding in the yarn by means of a suitable solvent. The selected number of warp and weft threads per unit area is so small that on the one hand an optimal fiber spreading is obtainable, but on the other hand, after activation of the potential fiber-spreading properties, sufficient cohesion of the fibers in the fabric is retained for further processing of the fabric. After obtaining the desired fiber spreading the fiber bonding, partially lost through the activation, is at least partially restored.

Abstract: An optical coupling body is disposed between first and second arrays of optical conductors mounted for rotation at equal but opposite rates relative to the body. Either light reflective or light transmissive means is arranged in the body to effect constant coupling of individual conductors in the first array with respective conductors in the second array.

Abstract: Threshold circuit for selecting video signals derived from small stationary and moving objects amidst an abundance of clutter in a harbor area. The threshold voltage generator (1) of this circuit is suitable for detecting the temporal average .DELTA.P of the positive peak value and the temporal average .DELTA.N of the negative peak value from the AC component of the applied video voltage (V.sub.DC +V.sub.AC) and for generating modified voltages (l+k)(V.sub.AC -.DELTA.P) and k(-V.sub.AC -.DELTA.N). The modified voltages together with the inverted video voltage are combined to form the threshold voltage V=V.sub.DC +.DELTA.P+k(.DELTA.P+.DELTA.N) being k times the average peak-peak value above the average peak value of the video voltage, where k is a constant.

Abstract: A digital scan converter is provided with a memory, each cell of which contains brightness data for presenting a corresponding video signals on a raster scan display at positions corresponding with the respective cells; a logical unit for supplying, in response to the applied video signals and the brightness data stored in memory, new brightness data overwriting that stored in memory; an address conversion circuit for converting the addresses established in polar coordinates into addresses expressed in Cartesian coordinates to store the new brightness data in memory; and with a circuit connected to the memory for reading out the brightness data and for presenting corresponding video signals on the raster scan display.