SU1166053A1 - Device for measuring duration of single pulse - Google Patents

Abstract

A DEVICE FOR MEASURING THE DURATION OF A SINGLE AND MULCA, containing two circulation units, the direct output of the first of which is a co-. Dinen with its first input, the output of the second circulation unit is connected to the input of the delay element and its own first input, two counters, two triggers, the first input of the first of which is connected to the input of the device, characterized in that three OR elements, two NAND elements and an inverter, the input to: is costly connected to the input of the device and the installation inputs of the first and second counters, the output of the inverter is connected to the second inputs of the circulation units, the direct output of the first circulation unit is connected to The first input of the first OR element, the second input of which is connected to the forward output of the first trigger and the output to the first input of the first AND-II element, the inverse output of the first circulation unit is connected to the first input of the second OR element, the second input of which is connected to the inverse the output of the first trigger and the first input of the third OR element, and the output to the second input of the first NAND element, the output of which is connected to the first input of the second trigger, the second input of which is connected to the output of the delay element and the second input of the third ele OR, whose output is connected to the first input of the second element of the NAND, the second input of which is connected to the output of the second. the trigger, and the output to the counting input of the second counter, the output of the second circulation unit is connected to the tre-. By the input of the first NAND element and the counting input of the first counter, O) the first output of which is connected to O) the second input of the first trigger, the second output of the first counter is connected to the third input of the second NAND element and the control inputs from the circulation units .

Description

The invention relates to a measurement technique and can be used to measure the duration of a single pulse. A device for measuring pulse duration and time intervals is known, which contains serially connected reference frequency generator, a key and a counter to the input of which is connected to a delay line with taps which are connected through the AND element with the inputs of the reference trigger, the output of which is connected to the control input of the key The disadvantage of the device is low measurement accuracy. The closest in technical essence to the invention is a device comprising a first closed circulation loop consisting of a first collection circuit connected in series, a first amplifier and a first delay element whose output is connected to the first input of the first collecting circuit and the first input of the first element 2I, the second input of the first collecting circuit is connected to the pulse bus of the end of the interval and to the input of the first trigger, a second closed loop, a circulation consisting of series-connected second circuit the second amplifier and the second and third delay elements; the second delay element is bridged with a key, the input of which is connected to the first output of the second trigger, the output of the third delay element is connected to the first input of the second element 2I, to the second input of the first element 2D, to the first input of the ZI element and to the first input of the second collection circuit, the first input of which is connected to the pulse bus of the beginning of the interval, the output of the first element 2I is connected to the first input of the second trigger and through the delay element to its second input, second the output of which is connected to the second input of the ZI element, the third input of which is connected to the first output of the first trigger, the second output of which is connected to the second input of the second element 2I, the output of which is connected to the input of the first counter, the outputs of which are connected to the first group of inputs of the decoder, the second the group of inputs is connected to the outputs of the second counter, the input of which is connected to the output of the ZI element, and the output of the decoder is connected to the inputs of the indicator 12. A disadvantage of the known device is the low measurement accuracy Due to the coincidence resolution time-element and trigger. The purpose of the invention is to increase the accuracy of measuring the duration of a single pulse. This goal is achieved in that a device for measuring the duration of a single pulse, containing two circulation units, the direct output of the first of which is connected to; with its first input, the output of the second circulation unit is connected to the input of the delay element and its own first input, two counters, two flip-flops, the first input of the first of which is connected to the input of the device, three OR elements, two AND-NOT elements and an inverter, input which is connected to the input of the device and the installation inputs of the first and second counters, the output of the inverter is connected to the second inputs of the circulation units, the direct output of the first circulation unit is connected to the first input of the first OR element, the second input of which is connected to the right the output of the first trigger and the output to the first input of the first NAND element, the inverse output of the first circulation unit is connected to the first input of the second OR element, the second input of which is connected to the inverse output of the first trigger and the first input of the third RSHI element, and the output is to the second input of the first NAND element, the output of which is connected to the first input of the second trigger, the second input of which is connected to the output of the delay element and the second input of the third OR element, the output of which is connected to the first input of the second AND AND NOT element, W which input is connected to the output of the second trigger, and the output to the counting input of the second counter, the output of the second circulation unit is connected to the third input of the first, the NAND element and the counting input of the first counter, the first output of which is connected to the second input of the first trigger, the second the output of the first counter is connected to the third input of the second NAND element and the control inputs of the circulation units. FIG. 1 shows the functional scheme of the device; in fig. 2 time diagrams for his work. The device contains circuits 1 and 2 of circulation, combined by the inputs of the inverter 3, the input of which is the input of the device, the elements OR 4 and 5, the counter 6, the trigger 7, the delay element 8 connected in series, the trigger. 9, the element AND-NOT 10 and the counter 11, the first input of the element OR 4 is connected to the forward output of the circulation unit 1, the element OR 12 and the element AND-NO 13, the output of which is connected to the first input of the trigger 9, and the first, second and the third inputs are connected to the outputs of the OR 4 elements and the circulation block 2, the output of which is also connected to the inputs of the delay element 8 and the counter 6, the first output of which is connected to the trigger input 7, and the second output to the control inputs of the blocks 1 and 2 circulations and with one of the inputs of the element AND-NOT 10, the first input of which is connected The input of the element is OR, the second input is connected to the output of the delay element 8, and the first input is connected to the input of the element OR 5 and the output of the trigger 7, the direct output of which is connected to the second input of the element OR 4, and the first input of the element OR 5 is connected to the inverse output of the circulation unit 1, and the first input of trigger 7 and the installation inputs of counters 6 and 11 are connected to the input of the device. Circulation blocks 1 and 2 are performed on elements of the NAND type digital logic and delay elements, such as high-frequency coaxial cable, for example. The device works as follows. Measured single pulse of duration T | through the inverter 3 it enters the inputs of blocks 1 and 2 of circulation on the codes of which a series of pulses is formed with a circulation period of TC1 in block 1, and TTs in block 2 (Fig. 2 a, b) and TC2 TTs, LTs (4Tc is the difference during the circulation period, determined by the required measurement accuracy). Duration Tffj, TC., More than twice the duration T The sequence of pulses from the direct output of block 1 is fed to the input of the element OR 4, the ac of the inverse output goes to the input of the element OR 5, to the other inputs of which arrive respectively the logical O and logical 1 from the outputs of the trigger 7 Counter 6 counts the number of circulation in the circuit, and when the circulation number is equal, n / 3T, i.e. when the pulse circulating in block 2 goes beyond the limits of possible coincidence with the pulse circulating in block 1, the signal from the output of counter 6 changes the state of trigger 7 (time t, fig. 2 and). Thus, at the outputs of the elements OR 4 and 5, the sequences shown in FIG. 2 v, d. The indicated pulse sequences are fed to the inputs of the NAND 13 element, which also receives the sequence from the output of block 2, and | output element. AND-NO 13, when coincidentally at the inputs of logical units, logical zeros are formed (Fig. 2 d). Up to the moment t., The number of such zeros corresponds to the number of temporal coincidences of pulses circulating in both blocks 1 and 2. The indicated zeros reset to the logical position O at the output trigger 9 (Fig. 2 g), which is reset to its initial state by the delay in element 8 delays by a pulse (fig. 2 e) from the block 2. Unused because of the low resolving time of the trigger 9, the zeros are shown. 2 d by dashed lines. Logic zeros from trigger 9 are received (Fig. 2 g) to the NAND element 10, to the other inputs of which logical 1 comes from the output of counter 6 and up to the time t logical from the output of the element. OR 12 (Fig. 2 h), blocked, logical 1 from the output of the trigger 7. Thus, the counter 11 until the time t fixes the number of pulses at the output of the trigger 9, which is shown by the solid line in FIG. 2 and. This number is different from the real number of sov-. pulse drops in blocks 1 and 2, which is shown by the dashed line in FIG. 2 and. To restore the actual number of matches, start at time t. , the formation of the number of coincidences of the pulse begins in block 2 (Fig. 2 b) with a pause in

block 1 (Fig. 2 a, b). Starting from the moment t (Fig. 2 and), the pulses corresponding to the pause from the inverse output of block 1, pass through the element OR 5 (Fig. 2 g) to the input of the AND-HE element 13, forming its output (Fig. 2 e) dogic O, corresponding to the coincidence of the pulses (Fig. 2 b) and pauses of the Fig. 2- g). These zeros are reset from the logical O position at the output of the trigger 9. (Fig. 2 g), which is restored to its initial position by a pulse from the output of the delay element 8 (Fig. 2 e). Unregistered matches (shown by a dashed line in Fig. 2d) cannot overturn trigger 9, the ion remains in the position of logical 1 at the output. Since the OR element 12 from the moment t is not blocked by logical 1 from the output of trigger 7, then. at its output, pulses are formed (fig. 2h), corresponding to the pulses from the output of delay element 8. The coincidence of logical units at the inputs of the AND-NOT 10 element is now possible only if the state of the trigger 9 does not change (Fig. 2 g), i.e. when no coincidence of pulses and pauses is recorded. Since the process of pulse output of block 2 and pulse and pause of block 1 is completely identical (determined by the resolution time of the element IS-NE 13 and the trigger 9), up to the time tj the number 11 corresponding to the true number of pulses coincides is equal to N. The moment tg is determined repetition of the original sieve, b) and corresponds to the action (Fig. 2 a,

the circulation number n () + 1. This number is counted by counter 6,

the signal from the output of which, arriving at the control inputs of blocks 1 and 2, stops the circulation of pulses, as well as entering as logical O at the input of the AND-NOT element 10, stops changing the number in the counter 11. The next measured pulse arriving at the installation inputs of counters 6 and 11 and the trigger input 7, reset the device, after

which measurement process is repeated.

Thus, the value of the pulse duration is determined with an accuracy higher than in the known device.

Claims (1)

DEVICE FOR MEASURING A SINGLE PULSE DURATION, containing two circulation units, the direct output of the first of which is connected to its first input, the output of the second circulation unit connected to the input of the delay element and its own first input, two counters, two triggers, the first input of the first of which is connected to device input, characterized in that, in order to increase accuracy, three OR elements, two AND-NOT elements, and an inverter, the input of which is connected to the device input and installation inputs of the first and second counters, are introduced into it sensors, the inverter output is connected to the second inputs of the circulation units, the direct output of the first circulation unit is connected to the first input of the first OR element, the second input of which is connected to the direct output of the first trigger, and the output to the first input of the first element AND, the inverse output of the first circulation unit connected to the first input of the second OR element, the second input of which is connected to the inverse output of the first trigger and the first input of the third OR element, and the output to the second input of the first AND-NOT element, the output of which is connected to the first the second trigger, the second input of which is connected to the output of the delay element and the second input of the third OR element, the output of which is connected to the first input of the second AND-NOT element, the second input of which is connected to the output of the second trigger, and the output to the counting input of the second counter, the output of the second circulation unit is connected to tre. the fourth input of the first AND-NOT element and the counting input of the first counter, the first output of which is connected to the second input of the first trigger, the second output of the first counter is connected. dinan with the third input of the second AND-NOT element and the control inputs of the circulation units. 1 1166053 2