SU857887A1 - Radio pulse filling frequency meter - Google Patents

Description

(54) MEASURING RATE OF FILLING RADIO IMPULSES

The invention relates to a measuring technique and can be used in devices for measuring the frequency of filling - radio pulses. Known meter filling frequency radio pulses, containing serially connected reference frequency generator, block selection, frequency divider, the first pulse counter and an arithmetic unit, as well as a pulse shaper, the output of which is connected through the second selection block to the first input of the second pulse counter, element And and the one-shot 1 However, this device does not allow the use of the entire duration of the radio pulse to form a measuring interval and, therefore, does not allow improve the accuracy of automatic measurement of the frequency with increasing RF pulse duration. It is also known a device for measuring the frequency of filling of radio pulses, containing in series a reference frequency generator, a selection unit, a first counter and an arithmetic unit, the second input of which is connected to the output of the second counter, an input pulse generator, a series-connected delay pulse generator, write and reset, and the fourth counters, memory blocks and comparisons, the first and second element AND, the element OR, the decipher, control triggers 2. The disadvantage of this device is its complexity. The purpose of the invention is to simplify and increase the reliability of the device. This goal is achieved by the fact that in a known filling frequency meter containing a series-connected reference frequency generator, a selection unit, a first counter and an arithmetic unit, the second input of which is connected to the output of the second counter, an input pulse generator connected in series to the delay, recording and reset pulse formers , the third and fourth counters, the memory block, the comparison block, the first and second element And, the first and second trigger, and the driver of the input pulses is connected to the input ode the pulse delay generator with the first input of the first element I and the first input of the third counter, the second input of which is connected to the output of the reset pulse generator, and the outputs of the third counter are connected with the first inputs of the comparison unit, the outputs of the comparison circuit whose output is connected to the first input of the first trigger, and the second inputs of the comparison unit are connected to the outputs of the memory unit, the first input of which is connected via the second element I to the output of the write pulse generator and directly to the first input of the second about the trigger, the first output of which through the first element I is connected to the second input of the first trigger, the output of which is connected to the selection unit, the third element I is entered, the output of which is connected to the input of the second counter, and the inputs respectively to the second input and output of the first trigger, the first the input of which is connected to the input of the fourth counter, the output of which is connected to the second input of the second trigger, the second output of which is connected to the second input of the second element I, and the remaining inputs of the memory unit are connected to the outputs of the third account tchiku.

FIG. 1 shows a block diagram of a meter; in fig. 2 - time diagrams that show his work.

The frequency meter contains the shaper 1 input pulses, the first counter 2, the second counter 3, the first additional counter 4, the second additional counter 5, the memory block 6, the comparison block 7, the first trigger 8, the second trigger 9, the first element 10, the second element Both 11 and the third element AND 12, the reference frequency generator 13, the selection unit 14, the arithmetic unit 15, the control unit 16 consisting of drivers of the delayed pulses 17, recording 18, reset 19, input slots 20 and 21, output bus 22.

The device works as follows.

When a sequence of radio pulses is fed to the driver 1 via bus 20, rectangular short pulses are formed at its output (Fig. 2a) from the vibrations of the measured frequency filled by the radio pulse. These pulses are in the form of packs consisting, for example, of 1-8 pulses, which are fed to the second counter 3 and the driver 17 of the delay pulses of the control unit 16, which forms a rectangular pulse with a duration slightly longer than the pack duration at its output (Fig. 2b) . By the decay of this pulse, short write pulses are formed in the write pulse shaper 18 (Fig. 2c), the drop of which produces a reset pulse by the reset shaper 19 (Fig. 2 d) The input pulse wads also arrive at the first input of the first And 10 element locked in the second input is lowered from the output of the first trigger 8. The trigger 8 overturns (Fig. 2e) with a write pulse (Fig. 2c) that passed through the second element And 11 at its second input there is a high level (Fig. 2e) coming from the inverse trigger output 8, and opens first And 10, which from this moment is able to pass all the pulses of the second pack to the input of the second trigger 9. The first pulse of the second pack acts on the second trigger 9 so that its output sets a high level (Fig. 2 and) Output code of the second counter 3 after the end of the first burst, it is rewritten by the write pulse (Fig. 2c) into the memory block 6. The output of this block is connected to the input of block 7 of the comparison. In the interval between the first and second bursts, the information of the second counter 3 is reset by a reset pulse (Fig. 2 g) and, if necessary, a number corresponding to a possible decrease in the number of pulses in subsequent bursts due to the fluctuation of radio pulses and its filling frequency. For example, if the number of pulses of the first packet of 10 was recorded, then in the case of 8 pulses in the second pack, counter 3 should not be zeroed, but the number 2 should be entered into it. Numbers of bits of counter 3, in which the number must be entered at the moment of reset, before measurements, depending on possible changes in the number of pulses from pack to pack. To do this, counter 3 must have an appropriate circuit controlled by a reset pulse. The pulses of the second packet (. 2 a) arrive at counter 3 and change the code at its output to a value corresponding to the number of pulses in the packet plus the number entered artificially (according to our example 2). Then the changing code at the output of the counter 3 is compared in the comparison block 7 with the recorded code of the first packet in the memory block 6 (10 pulses recorded in this example). With the equality of these codes (which in this case corresponds to the moment of arrival of the 3rd pulse) in the comparison block 7 a pulse is produced (Fig. 2 e) corresponding to the end of the pack, which is then fed to the input of "Set. The second trigger 9 and the input of the first additional counter 4. The output signal of the second trigger 9 (FIG. 2 and) is fed to the selection unit 14, opening it to pass the signal of the reference generator 13 to the first counter 2. At the same time, the output signal of the second trigger 9 is fed to the first input of the third element is And 12, and the second input of this element receives a packet of pulses that have passed the first element And 10, beginning with the second package (Fig. 2 g). From the output of the third element And 12 packs of pulses arrive at the second

Additional counter 5 (Fig. 2k), where the number of pulses of all K-packs that have passed through the first element 10 and determined by the capacity of the first additional counter 4 is summed. The capacity of counter 4 can be preset depending on the desired number K by entering it the required number of input buses 21. As a result of the overflow of counter 4, a potential "measurement end" is formed at its output (Fig. 2L), which sets the first trigger 8 to its initial state, closing the second element And 1 G. The N code from the counter 2 and P a counter 5 enter the arithmetic unit 15, which calculates a frequency radio pulses fill the formula (1) and outputted to the output 22.

Thus, by determining the number of pulses in the first burst, it is possible to form measuring intervals from the next burst using the entire duration of the radio pulses. In the case of fluctuation of the duration and frequency of filling of radio pulses, the proposed device allows to ensure reliable measurements by automatically introducing the number into the lower bits of the second counter 3 of the corresponding expected fluctuation.

With the same quality indicators, the basic circuit of such a device contains 28 chips less than that of the known device.

Claims (2)

1. USSR author's certificate number 468848, cl. G 01 R 23/10, 18.09.74. 2. USSR author's certificate number 2491958, 03.06.77. nineteen JllMlllllllLJlJIJUlJlMJlllL FIG. year k-pa ka / fc naftca