RU2530225C1 - Selection method of pulses and pulse selector of semiactive target-seeking head - Google Patents

Abstract

FIELD: radio engineering, communication.

SUBSTANCE: method is implemented due to a pulse selector of a semiactive target-seeking head of artillery shells rotating in roll direction, which contains a unit for separation of the first pulse, the first OR circuit, a delay element, a strobe shaping unit, an AND circuit, the first and the second matrix units, the second OR circuit, a multichannel amplifier, a comparator unit, a trigger unit, a pulse generator, a pulse counter, a register, a multiplying unit, a comparing device, a timer, a counter unit, a coding device, an emission receiver with sensitive elements and an AND-OR circuit with the corresponding communications.

EFFECT: reduction of time for searching and providing transition to a tracking mode at failure of one of the channels in the range of possible rotation frequencies.

2 cl, 1 dwg

Description

The proposed group of inventions relates to methods and devices for selecting pulses of semi-active homing heads used to generate control signals for rotating artillery shells and missiles.

A known method of pulse selection, implemented in patent No. 2073953, class. Н03К 5/26 from 04.11.93, which consists in setting the permissible deviation of the pulse repetition period, setting the number of hits in the specified interval, determined by the permissible deviation of the repeating period from the given, setting the number of permissible misses in the specified interval. In this case, the first pulse arriving is taken to belong to the desired pulse sequence. Next, the intervals of the pulses are formed in such a way that the middle of the interval is separated from the first incoming pulse by a time equal to the specified pulse repetition period, and the interval duration is equal to twice the permissible deviation of the pulse repetition period. When another impulse hits the time interval thus formed, the current number of hits increases, and the number of misses is taken equal to zero. Upon reaching a given number of hits, the last of a given number of pulses is considered to belong to the desired sequence and, starting from it, tracking is carried out. When the specified number of misses is reached, the search process is repeated. The selector in which the above method is implemented comprises a first pulse extraction unit in series, a first “NOT” element, a first “OR” element, a delay element, a first strobe driver, a second “OR” element, a first and second “AND” elements, in series connected restart circuit, hit counter, hit counter, second “NOT” element, second strobe driver and third “OR” element, as well as an adjustable delay device. The output of the first pulse extraction unit is connected to the second inputs of the strobe generator and the restart unit, the output of the first “NOT” element is connected to the second input of the second OR element, the output of the first strobe driver is connected to the third input of the restart circuit, the output of the second OR element is connected to by the second inputs of the hit counter and the adjustable delay device, the output of the first AND element is connected to the third inputs of the hit counter and the adjustable delay circuit, the first inputs of the restart circuit and the allocation unit the first pulse and the second inputs of the counter failure and the first element "OR". The output of the restart circuit is connected to the first inputs of the failure counter and the first pulse allocation unit. The output of the hit counter is connected to the fourth input of the restart circuit, the first input of the adjustable delay device and the second input of the second AND element. The output of the adjustable delay device is connected to the second input of the second gate driver, and the output of the third OR element is connected to the second input of the second AND element. When fixing the necessary number of pulses by the hit counter, the selector switches to the tracking mode for the input pulses. In this case, the generation of strobe pulses is carried out in accordance with the current period of the input signal, and repeated search is prohibited. When the counter fixes a predetermined number of missed pulses in a row, a repeated search for input pulses is performed.

The described method of selection and the device are effective when used in homing heads in the presence of single gaps in the input pulses due to fluctuation of the energy received by the sensitive element of the radiation receiver at a threshold level of the input signal, as well as when the scattering spot hits the dividing line of the sensitive elements, since when dividing the spot, the energy attributable to each sensing element decreases. If one of the channels for generating a signal from the sensitive elements fails or is disconnected due to an increase in the noise level, for example, due to aging of the sensitive element or the impact of a single blow during firing, the number of omissions increases, which leads to an increase in the search time, and at the frequency of rotation of the projectile or rockets:

f≥0.75 / [(m-1) · T],

where f is the frequency of rotation of the projectile or rocket,

m is the number of pulses required to enter the tracking mode,

T - the repetition period of optical pulses,

the lack of transition to tracking mode, i.e. to capture the target.

The objective of the proposed group of inventions is to reduce the search time and ensure the transition to the tracking mode when one of the channels fails in the range of possible rotation frequencies.

This problem is achieved by the fact that in the known method of pulse selection, which consists in setting the permissible deviation of the pulse repetition period, setting the number of hits in a given interval, determined by the permissible deviation of the repetition period from the given, setting the number of permissible misses in a given interval, the first one the impulse is taken to belong to the desired sequence of impulses, the intervals of impulse hit are formed in such a way that the middle of the interval is separated from the first impu for a time that is a multiple of a given pulse repetition period, and the interval duration is twice the permissible deviation of the pulse repetition period, when a next pulse falls into the time interval thus formed, the current number of hits is increased, and when the specified number of hits is reached, the last of the given number of pulses is considered to belong to the desired sequence and, starting from it, carry out tracking, upon reaching a given number of misses, the search process by secondly, additionally set the angles that determine the relative position of the sensitive elements of the radiation receiver, the duration of the measuring interval and the permissible limits of change of signals from the sensitive elements, determined by the value of the probability integral for the normal distribution, form the measuring interval, on which the value of the probability integral is determined as the ratio of the time during which the signal level from the sensor exceeds the detection threshold For the duration of the measuring interval, sensitive elements, the value of the probability integral of which is outside the permissible limits, are excluded from work, pulses are formed with a repetition period equal to the period of rotation of the projectile along the roll, the frequency of rotation of the projectile along the roll is measured, after receiving the illumination pulse, determine from the direction of rotation, the angular velocity of rotation along the roll and the relative angular arrangement, the sensing element, which should take the next impulse of illumination, while if this If an element is excluded from work, then the increment of the number of misses is prohibited.

The described method is implemented in the proposed pulse selector, which contains a series-connected unit for extracting the first pulse, a first OR circuit, a delay element, a strobe forming unit, an I circuit, a first and second conversion blocks and a second OR circuit, the output of the And circuit being additionally connected to the second inputs of the block the formation of gates, the first and second circuits OR, the second conversion block, the first output of the block formation of gates is additionally connected to the second input of the first conversion block, the second output of the block of gates are connected to the third input of the first OR circuit, the output of the second OR circuit is connected to the third input of the first conversion unit, the output of which is connected to the first input of the first pulse extraction unit, the output of the second conversion unit is the output of the pulse selector, into which an additional multi-channel amplifier is additionally connected , a comparator unit and a trigger unit, a pulse generator, a pulse counter, a register, a multiplication unit and a comparator, connected in series with a single timer, counter unit and encoder, as well as a radiation receiver with sensitive elements and an AND-OR circuit, with the output of the comparator connected to the fourth input of the first conversion unit, the second input of the comparator connected to the output of the encoder, the generator output additionally connected to the timer input and by the second input of the counter block, the output of the counter block is additionally connected to the second input of the comparator block, the output of which is additionally connected to the third input of the counter block, and through the I-IL circuit - with the second inputs of the extraction block of the first pulse and the And circuit, the first output of the strobe block is additionally connected to the second input of the trigger block, the outputs of the sensitive elements of the radiation receiver are connected to the input of a multi-channel amplifier, the timer output is additionally connected to the second input of the AND-OR circuit, the output of the block flip-flops is connected to the second input of the encoder, the second inputs of the register and the pulse counter receive pulses with a frequency of rotation of the homing head, a code is sent to the second input of the multiplication unit, with corresponding to the value of the period of the illumination pulses, and the reference voltage to the third input of the comparator unit.

The drawing shows a structural diagram of the proposed pulse selector, where

1 - multi-element, for example, a quadrant radiation detector (PI);

2 - multichannel, for example, four-channel amplifier (CU);

3 - block comparators (BC);

4 - pulse generator (G);

5 - timer (TM);

6 - block counters (BS);

7 - pulse counter (ST);

8 is an AND-OR diagram;

9 - encoder (W);

10 - trigger block (BT);

11 - register (WG);

12- multiplication block (BOOM);

13 - a comparative device (SU);

14 - block allocation of the first pulse (BPI);

15 - scheme I (I);

16, 19 - conversion blocks (PB1, PB2);

17, 20 - OR circuits (OR1, OR2);

18 - block formation of the strobe (BFS);

21 - element delay (EZ).

The pulse selector operates as follows.

When power is applied to the pulse selector and the presence of target illumination pulses, the output signals are formed at the outputs of the multi-channel amplifier 2, which are determined both by the presence of a backlight pulse and the level of intrinsic noise of the sensitive elements of the radiation receiver (PI) 1.

Generator 4 generates clock pulses arriving at the second input of the block of counters 6 and at the input of the timer 5, which generates a count resolution signal that determines the duration of the measuring interval T, which in turn goes to input 1 of the resolution of counting of the block of counters 6 and to the second input of the AND-OR circuit 8, blocking the passage of pulses to the second inputs of the circuit And 15 and the allocation unit of the first pulse 14, thereby excluding the selection of input pulses during the test of operability of the sensitive elements of the radiation receiver 1. In the presence of logic 1 at the output of one of the comparators of the block of comparators 3 during the pulse action, the pulse counting is enabled for the corresponding counter of the block of counters 6. In this case, the time spent by the output of each of the comparators of the first and second blocks of the comparators 3 in a single state t is determined by the ratio:

$$t=T\cdot (\mathrm{one}/2\pi {\sigma }_w)\cdot {\displaystyle \underset{U_o}{\overset{\infty }{\int }}\exp (-x^2/2{\sigma }_w)dx\text{(one)}}$$

where σ _w - s.k.o noise

T is the duration of the measuring interval, equal to (0.1-0.3 s);

U ₀ is the threshold voltage.

The number of pulses n accumulated by the corresponding counter at the end of the measuring interval is determined by the ratio:

$$\text{n}={\text{f}}_{\text{0}}\cdot t,\text{(2)}$$

where f ₀ is the clock frequency of the generator.

The number of pulses required to switch the high order of the counter, which is the output of the corresponding channel of the counter block 6, to the logical state 1, is determined by the relations (1), (2) for a given critical ratio σ _w and U ₀ , at which reliable selection of pulses is ensured. At the same time, at the outputs of the counter blocks of the corresponding channels, the signal-to-noise ratio for which is lower than critical, there is a logical 1 that prohibits the formation of pulses on the corresponding noise channel of the output of the comparator unit 3, and thus eliminating the possibility of false pulse selection. Providing a condition for turning off the channel (the presence of a logical unit in the high order) in the absence of pulses at the output of the corresponding comparator of the comparator unit 3 is achieved by pre-writing the value minus 1 to the pulse counters of the counter unit 6. At the end of the measuring interval T, voltage pulses proportional to the output of the radiation detector 1 are generated the radiation energy incident on each of the sensitive areas of the radiation receiver 1. The amplified pulses from the output of the multi-channel amplifier 2 arrive t to the input of the block of comparators 3. When the pulse amplitude of one of the channels exceeds the threshold voltage (U ₀ ), pulses are generated at the output of the block of comparators 3, which pass through the AND-OR circuit 8 to the input of the block of allocation of the first pulse 14 and circuit I 15. The first pulse from the output of the extraction unit of the first pulse 14 and the first circuit OR 17 is fed to the input of the delay element 21. The delay element generates a start pulse of the gate formation block 18 after a time T ₁ determined by the ratio:

, $${\text{T}}_{\text{one}}={\text{T}}_{{}_{\text{0}}}{\text{-t}}_{\text{C}}\text{/ 2 (3)}$$

,

where T ₀ - the repetition period of the backlight pulses,

t _C is the duration of the strobe.

When the following input pulses fall into the gated interval, gated pulses are formed at the output of circuit And 15, restarting the delay element 21. If the number of gated input pulses is sufficient to set the high-order bit of the second counting unit 19 (hit counter), which is its output, to logical state 1 , the signal from the output of the conversion unit 19 passes through the OR circuit 20 to the input of the first conversion unit 16 (non-hit counter) and holds it in the reset state, thereby prohibiting repeated searches Khodnev pulses - pulses selector switches to a tracking mode for input pulses. The output signal of the pulse selector informs external devices about a change in operating mode. If there is an unacceptable noise level at the output of one of the amplifier channels of the multi-channel amplifier 2, a logical 1 is formed at the corresponding output of the counter block 6, thereby fixing the number of the failed channel. In this case, the corresponding comparator of the block of comparators 3 is held in the initial state, i.e. the input pulse that has fallen on the sensitive element of the radiation receiver associated with the disconnected channel will be skipped. Prediction of gaps in the illumination pulses due to their contact with a sensitive element associated with a disconnected channel is carried out as follows. When the projectile and the associated homing head rotate, T _BP pulses are formed with a repetition period equal to the duration of one revolution. The pulse counter 7, using the clock pulses of the generator 4, generates a code corresponding to the current time relative to the appearance of the previous pulse T _BP . The next pulse T _BP rewrites the contents of the counter 7, which is proportional to the period of rotation of the homing head, to register 11, and from its output to the first input of the multiplication block 12. The code of the period of the repetition of the backlight pulses is received at the second input of the multiplication block, and a code is generated at the output of the multiplication block 13 corresponding to the rotation angle of the homing head for the illumination period N _φ . At the same time, a code is generated that is inverse to the contents of register 11, and then the resulting code is multiplied with the code present at the second input of the multiplication unit 12. When a next illumination pulse is received, the code corresponding to the number of the sensing element received at the second input is stored in the trigger block 10 the encoder, the first input of which receives the number code of the disabled channel. Under their influence, the encoder generates codes corresponding to the minimum N ₂ and maximum N ₁ angular misalignment of the boundaries of the radiation detector that is disconnected and receives the last pulse of illumination, which is necessary to compensate for the uncertainty of the position of the scattering spot on the sensitive elements along the roll angle. The comparing device 13 compares the angular mismatch codes with the angle of rotation of the homing head for the period of repetition _{of the} backlight pulses and when the condition N ₁ ≥N _φ ≥N ₂ is fulfilled, it generates a blocking signal of the first conversion block 16. Otherwise, in the absence of a gated pulse, the content of the first conversion block 17 increases and when it is full, the pulse selector starts a second search for optical pulses. The initial state of the pulse selector after turning on the power source is provided by the installation pulse generated after power is applied. This pulse resets the first (16) and second (19) conversion blocks.

The pulse selector is made using standard microcircuits. As a photodetector, FUL-113 type devices are used. In the block of multi-channel amplifiers, the chip 1486UD4 is used, as a comparator, a chip of type 1121CA1 is used. The remaining analog nodes are made on the operational amplifiers of the 140 series. The digital part can be performed on the 533 series microcircuits or using programmable devices. A feature of constructing conversion blocks is the blocking of the account in the presence of a logical unit in the highest order. The pulse counters of the block of counters 6 contain elements of the preset of all bits in the state of a logical unit. If there is a logical unit in the high order and a logical zero in the rest, the count stops.

Claims (2)

1. The method of selection of pulses by a semi-active homing head of artillery shells and missiles rotating along the roll, which consists in setting the permissible deviation of the pulse repetition period, setting the number of hits in a given interval, determined by the permissible deviation of the repetition period from a given, setting the number of permissible misses in a given the interval, the first incoming pulse is taken to belong to the desired sequence of pulses, form the intervals of the pulses in such a way that the middle of the interval is separated from the first incoming pulse by a time multiple of the specified pulse repetition period, and the interval duration is equal to twice the permissible deviation of the pulse repetition period, when the next pulse falls into the time interval thus formed, the current number of hits is increased, and when the specified number of hits is reached, the last of the given the number of pulses is considered to belong to the desired sequence and, starting from it, they monitor when they reach the specified the number of misses is repeated the search process, characterized in that it additionally sets the angles that determine the relative position of the sensitive elements of the radiation receiver, the duration of the measurement interval and the permissible limits of change of signals from the sensitive elements, determined by the magnitude of the probability integral for the normal distribution, form the measurement interval in which for of each sensitive element, the value of the probability integral is determined as the ratio of the time during which The signal from the sensitive element exceeds the detection threshold, by the duration of the measuring interval, sensitive elements, the probability integral of which is outside the permissible limits, are excluded from operation, pulses are generated with a repetition period equal to the period of rotation of the projectile along the roll, measure the frequency of rotation of the projectile along the roll, after receiving the backlight pulse, based on the direction of rotation, the angular velocity of rotation of the roll and the relative angular location, the sensing element, which must take the next backlight pulse, and if this sensitive element is excluded from work, then the increment of the number of misses is prohibited. 2. A pulse selector for a semi-active homing head of artillery shells and missiles rotating along a roll, comprising a first pulse extraction unit, a first OR circuit, a delay element, a strobe forming unit, AND circuit, the first and second conversion blocks and a second OR circuit, with the circuit output And additionally connected to the second inputs of the gate formation block, the first and second OR circuits, the second conversion block, the first output of the gate formation block is additionally connected to the second input of the first ne the counting unit, the second output of the strobe forming unit is connected to the third input of the first OR circuit, the output of the second OR circuit is connected to the third input of the first counting unit, the output of which is connected to the first input of the first pulse extraction unit, the output of the second counting unit is the output of the pulse selector, characterized in that a series-connected multi-channel amplifier, a comparator unit and a trigger block, series-connected pulse generator, pulse counter, reg tr, a multiplication unit and a comparator, a timer connected in series, a counter unit and an encoder, as well as a radiation receiver with sensitive elements and an AND-OR circuit, the output of the comparator connected to the fourth input of the first conversion unit, the second input of the comparator connected to the output of the encoder , the generator output is additionally connected to the timer input and the second input of the counter block, the output of the counter block is additionally connected to the second input of the comparators block, the output of which is additional but it is connected to the third input of the counter block, and through the AND-OR circuit to the second inputs of the first pulse extraction unit and the AND circuit, the first output of the strobe forming unit is additionally connected to the second input of the trigger block, the outputs of the sensitive elements of the radiation receiver are connected to the input of the multi-channel amplifier, the timer output is additionally connected to the second input of the AND-OR circuit, the output of the trigger block is connected to the second input of the encoder, pulses with a rotational speed of the heads are received at the second inputs of the register and pulse counter homing, the second input of the multiplication unit enters the code corresponding to the value of the period of the illumination pulse, and a third input of comparators blocks - reference voltage.