FR2548347A1 - PROCESS FOR PRODUCING AN IGNITION SIGNAL AND DETECTION AND IGNITION DEVICE WITH SEVERAL DETECTORS - Google Patents

Abstract

PROCESS FOR OBTAINING AN IGNITION SIGNAL 3 AND DETECTION AND IGNITION DEVICE 1 HAS SEVERAL DETECTORS 4, 17. FROM EACH SIGNATURE OF DIGITIZED TARGET 27 TAKEN FROM THE OUTPUT SIGNAL 12 OF EACH DETECTOR, A CRITERION OF ' IGNITION 29, AND A TARGET PROBABILITY CRITERION 30 THAT CORRESPONDS TO IT, FROM A COMPARISON OF SPECTRAL OR OTHER INFORMATION WITH PREDETERMINED CRITERIA; THE PRIMING CRITERIA 29 MULTIPLIED BY THEIR TARGET PROBABILITY CRITERIA 30, TO DELIVER THE PRIMING SIGNAL 3, IS ONLY ADDED WHEN THE SUMMATION RESULT REACHES AT LEAST A PREDETERMINABLE THRESHOLD VALUE. TO REDUCE THE LIKELIHOOD OF FALSE TARGET DETECTION BY PROCESSING OUTPUT 12 SIGNALS FROM THE DETECTOR FROM A LARGE DISTANCE 21 TO THE TARGET, AT LEAST ONE OUTPUT 12 SIGNAL CAN BE DRAWN FROM ONE OF THE DETECTORS A COEFFICIENT DEPENDING ON THE TARGET. DISTANCE 37 WHOSE VALUE INCREASES AS WE APPROACH THE TARGET AND WHICH ALSO MULTIPLIES THE CURRENT START-UP CRITERIA 29 BEFORE THEY ARE ADDITIONAL ALGEBRAically.

Description

Method of producing an ignition signal and device

  detection and ignition system with several detectors.

  The present invention relates to a method of producing an ignition signal at the time of detection of a target-from ignition criteria provided by multiple detectors, acquired in separate information processing channels and then combined , as well as a multi-detector detecting and igniting device having a multi-channel information processing device 10 to provide ignition criteria to a logical combination device of the information for providing an ignition signal at the time of detection of a target object, intended in particular to provide the ignition signal of the

  active charge of a munition body carried.

  The method and the ignition sensor device of this type are known from DE-B 2 608 067. Each of the ammunition bodies worn can be ejected from a carrier body to be fired by passing over the area of the target. is designed so as to be able to attack, during the braked descent in the target area, a target object which is detected therefrom from the descent path, and to serve as a mine after landing in the area of the target. target, in the case where the target object would not yet be detected Because of these different driving data, several detectors are provided to provide ignition criteria that can be combined with one another by means of logic circuits, for provide

  the ignition signal itself when the target is detected.

  The disadvantage of this method of producing the ignition signal from the logical combination of ignition criteria obtained differently is that, on the one hand, an OR logic circuit does not increase the probability of detection in any way. of the target, since each igniting criterion alone triggers the ignition signal, even when there are different false target signalizations on the input channels of the OR circuit, while, d on the other hand, in the case of a logical combination AND of several ignition criteria, it is not at all possible to attack the target, when only one of the criteria

handsets is absent.

  As a result, the invention is based on the fact that, in order to succeed in the attack, it is certainly fundamentally correct to increase the probability of detection of the target by the combination of several ignition criteria obtained separately, but that this is not the case. must not cause the ignition signal to be blocked for the absence of a single one of all the ignition criteria envisaged. In particular, it is necessary to consider acquiring the different ignition criteria in an appropriate manner, in order to have a reliable identification. of the target, on the basis of information combined with different regions of the electromagnetic energy spectrum, such as by means of a detector responsive to thermal radiation and another detector responsive to the radiation of the millimeter frequency band. Although the infrared detector does not provide ignition criteria when the target is shrouded in thick fog, this should not be the case.

  blocking the delivery of the ignition signal when at least one other detector, for example a magnetic field or millimeter wave detector, has detected with a very high probability a target object to be attacked.

  In view of these data, the object of the invention is to improve a method or device of detection and ignition of this type by increasing the probability of detection of the target by using several different detectors at the same time, without the failure of a single channel

  detection prevents triggering of the ignition signal, when it is certain that the target has been detected.

  In order to achieve this objective according to the invention, a target probability criterion is assigned from the output signals of detectors which correspond to different spectra of the electromagnetic radiation of the target area, to each ignition criterion. the ignition signal is only delivered when a certain algebraic combination of the ignition criteria, each weighted by the criterion of probability corresponding to it, has reached a certain threshold, and it is anticipated, on the other hand, that multiple detectors designed for different electrical radiation spectra of the target region, each followed by a channel of

2548347.

  information to provide the corresponding ignition criterion and a target probability criterion corresponding to the logical data combining device, wherein

  the ignition criteria weighted by their target probability criteria are combined algebraically and transmitted to a threshold stage to deliver the ignition signal.

  The essential idea of this solution is thus to acquire in each detection channel not only an ignition criterion but at the same time information on the probability of the target (in the sense of the certainty that

  the target object detected represents a target to attack).

  We can then weight on each detection channel of the ignition criterion by multiplying it by its target probability criterion, then an algebraic combination of these information triggers the ignition signal when the result of the summation has reached This threshold value can be reached, since several ignition criteria of only average target probabilities are a sufficient sum in total, but also because an ignition criterion is not present at all or is only with a negligible target probability (for example, because of the absence of the radiation spectrum corresponding to this detector), but another criterion of initiation of very high proba25 target identification (eg because of very typical target identification data for the

  captured by another detector) is present.

  Moreover, in the estimation with multiplication of the ignition criterion, it can be taken into account that, when a target of a very great altitude is detected (because of the very great uncertainty of success of the attack by an active load of ammunition carried, which one still has, and of the general insecurity of the classification of targets from a high altitude), the ignition signal must be triggered only when the probabilities of target are already above the average It is necessary for this to have an estimate linked to the system by multiplicative combination with information depending on the distance of the target, before the summation

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  For example, it is possible to increase this height-dependent coefficient after the course of a certain height of fall from the ejection of the munition of the body which carries it, as a function of time, or the pass directly to 100% Indeed, when approaching close to the plane of the target, the ignition of the load

  Active should no longer be inhibited (in the hope that the probability will increase further), but shortly before the end of the fall, it is then acceptable for tactical reasons, even for relatively low target probabilities.

  It is thus possible to obtain, with relatively simple means of signal processing technique for output signals of different detectors, a high probability of effective attack of defined target objects. In particular, it is possible to use current sensors which are not at all suitable (without these signal processing means) for detecting targets, from a high ignition height, which would therefore make the active charge prematurely

  under the effect of false signals during the initial phase of the descent.

  Other features, variants and advantages of

  the invention will emerge from the detailed description which will

  follow of an exemplary embodiment of the invention, which has been shown only the essential in an extremely simplified manner The single figure of the drawing shows, in block diagram form, a detection and ignition device allowing to implement the method of producing a boot signal. The detection and ignition device 1 is mounted in a mounted ammunition body 2 (also called a small bomb or active ammunition to be dispersed) and serves to emit a signal 3 of ignition of its active charge 4, when a target object 5 is detected in the detection direction 6 The detection and ignition device 1 comprises a plurality of information processing channels, preferably two, 7, 8, as shown, operating in parallel, which join together in a logical combination device 9 that provides the ignition signal 3, when the target is detected At the same time, the information combining device 9, preferably in the form of a programmed processor, is designed under the form of a synchronization device 10 to output control program signals 11 appearing as a function of time, by means of which the digital processing of the information is controlled at the moment the digitization of the output signals 12 'of the detectors and after, such as the time course of the arming and auxiliary functions in connection with the availability for the ignition of the ammunition carried 2 The synchronization device 10 is triggered by a triggering information 13 from a defined initial state, which is transmitted to the ammunition carried 2 when it is ejected from its carrier body (not shown in the drawing) or after and can serve at the same time to activate the power supply of the ammunition detection and ignition device 1

scope 2.

  The two channels 7, 8 are designed for different radiation spectra, with regard to the electromagnetic energy emanating from the target object. Thus, in a preferred embodiment, channel 7 operates with an infra-red detector. red 14, sketched in the form of an optoelectronic transducer 15 behind a lens optics 16,

  and the other channel with a millimeter wave detector 17, 25 sketched in the form of an antenna 18 at the focus of a concentration reflector 19.

  The infrared detector 14 is preferably a conventional detector system which thus captures thermal radiation emanating from the target object itself or emanating from another source and reflecting on it. millimeters 17 is then in particular, preferably, an active radar system, when it must be used

  at the same time to determine the distance 21 to the target.

  However, it is in principle sufficient to realize it in the form of a passive system (radiometer principle), which captures only the high-frequency radiation reflected on the target 5 from outer space (respectively , the radiation of the target coming out on the back

plan of the target area).

  In each information processing channel 7, 8,

  the initial output signal 12 of the detector undergoes amplification and filtering, in a band-pass preamplifier 23 or in a microwave integrated circuit 24, for the low-low noise filtering and the high-pass elimination of the derivative.

  The output signal 12 'of the still analog detector, thus purified, is then digitized by means of an analog-digital transducer 25. Next is the digital processing of the information to obtain 1 ignition signal 3, which can be performed in A single processor 26 Its information capacity (number of bits) must be chosen according to the extent of the information and the time available during the descent path of the ammunition carried to identify the target 5, taking into account the organization of memory and the decentralized processing of information in calculation assemblies

  peripheral devices; in principle, taking into account realistic data in this respect, a 26-bit 16-bit processor is sufficient.

  In each channel 7, 8, from its digitized signature 27, by means of a characteristic analyzer 28, a boot criterion 29 is obtained, as well as a corresponding target probability criterion, and is transmitted

  to the information combining device 9.

  The priming criterion 29 can be interpreted as a preliminary ignition signal, but which does not effectively cause the emission of an ignition signal 3 only when its probability is very high, or at the same time another channels 7, 8 deliver an ignition criterion 29 of at least sufficient probability. The probability value is high when detection or identification criteria determined for the target object can be recognized. plus the raw ignition criterion 29, the target probability criterion 30 corresponding thereto, each analyzer of

  characteristics 28 comprises a comparator 31 receiving on the one hand directly and, on the other hand, also via an adaptive threshold stage 32, the signature 37 obtained from the output signal 12 'of the detector.

  The adaptive threshold stage 32 is automatically adjusted, depending on the level of background signal from the environment of the target object 5 (environmental noise) and first, during a certain descent time. initial, according to the operation of the detection and ignition device 1, after the occurrence of the triggering information 13, to an initial value, and then, from it, during the continuation of the descent , continuously on the basis of the variation of statistical information in the field. The target object 5 differs from this threshold information

  updated by a defined variation of the short-term amplitude statistics of its signature 27, which causes the activation of the comparator 31.

  At the appearance of the ignition criterion 29, the comparator 31 provides a signal to a characteristic extractor 33 which receives, in addition, the signature 27 directly. The variation in the time of the signature 27 (therefore the variation of its amplitude as a function of time) is analyzed in the absolute and with respect to the threshold value varying according to the decrease in the distance 21 of the target, in particular with regard to the frequency and the length of the exceeding of the threshold Il In the course of digitization in the transducers 25, the sampling rates should be correlatively adjusted as a function of time, a normalization of the signature 27, as described in German Pat. No. 3,133,570. optimally reduces the cost of processing the information, when compared with predetermined target identification criteria, within the feature extractor 33. target probability criterion simply by a calculation of the wanted signal-to-noise ratio in the detector output signal 12, or a sample recognition classification is carried out during a vector comparison, representing certain properties of the target by vectors in a multi-dimensional vector space, and the distance of the vector which is the resultant of all the partial features at the center or center of gravity of a specific subspace of the

  target representing an encrypted measure of the target probability of the ignition criterion 29 corresponding in time.

  In any case, each feature analyzer 28

  thus provides, by comparison with pre-determined information on typical target objects 5, a target probability criterion 30 in addition to the ignition criterion 29.

  Each ignition criterion 29 can then be combined by multiplication in a multiplier 34 with its target probability criterion 30 (a value between 0% and 100% inclusive), thus weighted by this criterion, so that the results The signal processing of the separate channels 7, 8 can then be combined without problems (i.e. without mutual blocking). For this, the multipliers 34 are followed by an adder 35. This is only when the result of the the algebraic addition reaches a predetermined value in a threshold stage 36, or even exceeds it, than the probability that at that moment a target object to be attacked by the active load 4 has been detected in the direction of

  detection 6 is sufficiently high, which immediately causes the emission of the ignition signal 3.

  It has been taken into account in the drawing that it may be appropriate to subject the already-weighted ignition criteria 29 to further systematic estimation. It consists in taking into account multiplication of a coefficient 37 depending on the altitude, obtained for example by a device 38 measuring the distance from the target In this case, that is to say, for the current determination of the distance 21 of the target, it is possible to provide a radar localization device (measurement of the time It is cheaper to continually determine the target distance 21 from an initial distance (given with the occurrence of trigger information 13) as the ammunition carried 2 becomes approaching the target area, for example by evaluating the variation depending on the distance of the average intensity of the radiation 20 or 22. The height evaluation 37 thus provided by the measuring apparatus 38 then allows , during the tra of the ignition criteria 29, to take account of the fact that the acquisition of the information in the channels 7, 8 begins as soon as the carrier body is ejected (appearance of the triggering information 13) and, consequently, At a high altitude, the reliability of the ignition criteria 29 is necessarily lower than for a distance 21 to the lower target. As a result, the estimation by the coefficient 37 ensures that for increasing distances 21 of the target, the firing signal 3 is only delivered in the presence of a growing target probability criterion 30, thus with increasing certainty that at that instant a target object When the distance 21 from the target decreases, the probability that an ignition criterion 29 effectively corresponds to a defined target object 5 and to attack increases systematically; therefore, as the distances 21 of the target decrease, the attenuation of the ignition criterion 29 weighted by the target probability can decrease, so the coefficient 37 of the multiplicative signal processing can be increased.

Claims (11)

  A method of producing an ignition signal at the time of detecting a target from ignition criteria provided by a plurality of detectors, acquired in separate information processing channels and then combined, characterized in that detector output signals corresponding to different electromagnetic radiation spectra of the target area are associated with each ignition criterion, a target probability criterion, and the ignition signal is only delivered when a certain algebraic combination of the ignition criteria, each weighted by the target probability criterion   corresponds, has reached a certain threshold.   Process according to claim 1, characterized in that each weighted ignition criterion is additionally subject to a   systematic estimation before the algebraic combination.   Process according to any one of the claims   1 and 2, characterized in that the algebraic combination is   an addition of the products of the ignition criteria and the target probability criteria.   Process according to any one of the claims   2 and 3, characterized in that the systematic estimation coefficient essentially comprises the instantaneous distance from a detector to a target object.   Process according to any one of the claims   previous ones, characterized in that the target probability criterion essentially comprises the ratio of the   detector output at background.   Process according to any one of the preceding claims, characterized in that the probability criterion   of target essentially comprises the distance of a vector resulting from several target criteria to the center or center of gravity of a subspace of a multi-dimensional vector space. 7 Multi-detector sensing and ignition device (1) (14/17) having multi-channel information processing device for providing ignition criteria (29) to a combination device 254834? 7   logic of the information (9) for delivering an ignition signal (3) at the moment of the detection of a target object (5), in particular for implementing the method according to one   any of the preceding claims aboard a body   ammunition device (2) carried, characterized in that it comprises a plurality of detectors (14/17) designed for different electromagnetic radiation spectra (20,22) of the target region, each followed by an information processing channel ( 7, respectively 8) to supply the corresponding criterion of matching (29) and a corresponding target probability criterion (30) to the logical data combining device (9), in which the ignition criteria ( 29) weighted by their target probability criteria (30)   are combined algebraically and transmitted to a threshold stage (36) to provide the ignition signal (3).   8 Device according to claim 7, characterized in that it comprises a multiplier (34) for multiplying the ignition criterion (29) of each channel (7,8) by the target probability criterion (30) corresponding thereto , multi20 plicators that are connected to an adder (35) located before the threshold stage (36).   9 Device according to any one of claims 7 and 8, characterized in that it comprises in each   channel (7,8) a feature analyzer (28) whose ex-tractor (33) associates, in accordance with the signal-to-noise ratio of the output signal (12) of the detector and / or its variation with time and / or deviations from predetermined target recognition criteria and / or   instantaneous distance (21) from the target, a target probability criterion (30) to an ignition criterion (29).   Device according to one of Claims 7 to 9, characterized in that the information combining device (9) and the characteristic analyzers   (28) are part of a digital processor (26) which also outputs information to a timing device (10) to obtain an altitude coefficient (37) and for other program-controlled operations in the body of   carried ammunition (2) and its ignition device (1).