SU1223167A1 - Meter of single radiofrequency pulse duration - Google Patents

Abstract

The invention relates to a measurement technique and makes it possible to reduce the measurement error of the duration of a radio pulse. The device contains a band-pass filter 1, a detector 2, large-scale amplifiers 3.1 ... Z.p, filters 4. 1, ..., 4 .p low-frequency, threshold blocks 5. 1,,., 5. П, peak detectors. With reset 6.1, ..., 6, п, keys 7.1, ..., 7. п, block 8 of the separation of the two largest of the input voltages, the switching block 9, block 10 of forming a read pulse and a reset and storing block 11. Block 10 of a read pulse and a reset pulse consists of sequentially connected p-input elements AND, a differentiating circuit and a delay line. The inputs of the AND elements are the inputs of the device, the output of the delay line is connected to the reset bus of the detector 2, and the output of the differentiating circuit is connected to the read bus. 1 il. i SL 13-

Description

The invention relates to a measurement technique and is intended to measure the duration of a radio pulse under conditions where the duration of the measured radio pulse varies widely.

The purpose of the invention is to reduce the measurement error of the duration of radio pulses,

The drawing shows the scheme of the proposed meter for the duration of single radio pulses.

The device contains a band-pass filter 1, a detector 2, large-scale amplifiers 3.1, ..., 3, p, filters 4.1, ..., D of low frequencies, threshold blocks 5.1, ..., 5. n, peak detectors with reset 6.1, ..., 6.p (PD), keys 7.1, ..., 7.p, block 8 of the allocation of the two largest of the input voltages, decision block 9, block 10 of the formation of a read and reset pulse, which stores block (ST) 11.

The output of the bandpass filter 1 through the detector 2 is connected to the inputs of the large amplifiers 3. The output of the i-ro large-scale amplifier 3..i is connected via the i-th filter 4.1 to the inputs of the 1st block 5.1 and i-r o PD with reset 6.1. The control inputs of the unit 5 are combined with the control bus, and the outputs of the 1st: block 5.1 are connected to the 1st input of the n-input block 10 of the read and reset pulse and to the control input of the 1st PD 6.1 .. Bus reset unit 10 is connected to the reset inputs 6.1, and the output of the 1st PD 6.1 is connected via the 1st key 7.1 to the 1st input of the p input block 8 of the two largest of the input voltages, the first and second outputs of which are connected to the corresponding inputs - ka 9, and the third and fourth outputs to the first and second inputs of block 11, the first and second outputs of which th connected to third and fourth inputs of unit 9. The control inputs of the keys 7 are connected to a bus 10 read block.

The read and reset pulse shaping unit 10 consists of sequentially connected p-input elements AND, a differentiating circuit and a delay line (LZ). The inputs of the input and output are the inputs of the device, the output of the LZ is connected to the detector's reset bus, and the output of the differentiating circuit is connected to the counter.

Solving unit 9 calculates the duration of the radio pulse by the formula

and about . ., Rm c i

(one)

Jzo

where and - the signal arriving at p.rvy input unit 9; - signal received by 1Y to the second input of block 9; ct, jp; are the coefficients arriving at the third and fourth inputs of block 9 from ST 11. The ST 11 serves to store the pairs of coefficients Pi calculated in advance (p-1) and feed them to the inputs of block 9. Coefficients oi; out of STB 11, when two codes of two channels are received from block 8, corresponding to the two maximum voltages received in block 8 from the outputs of the keys 7. It is practical to choose the cutoff frequencies of the filter 4 and the corresponding agreed pulse durations so that

formed a geometric progression / „ft / yls ,, Lj H c-i J h - q

. ; ,

fo fi. - q f, f q f, ... ,

f, f ,,

where q is the denominator of the progression. In this case, the most economical

equipment is used and coefficients c are uniformly expressed, and which are equal

wasps, K; / LP

i-o

C2)

Where

r1

 .- u

ALIN

To "Afi / ufu.

p - integer, rounded to the larger value of the expression

)

For normal operation of the device, the gain factor K. a large-scale amplifier 3.1 of the 1st channel is selected using the ratio

TO; , (3)

where is the gain of the first

channel.

The choice of the magnitude of the gain factor K is not critical and can be taken to be equal to one. At the same time rms

the noise value at the outputs of all channel amplifiers is the same and equal to the input rms noise value.

Principle of operation meter length

following. A square radio pulse of duration, Sc, arrives at the input of the device and at the output of the bandpass filter 1 and detector 2 and is converted into a video pulse, which is amplified by scale amplifiers 3.1, ... Cp, passes through filter 4 and appears at the inputs of blocks 5.1 ,. .., 5.p.

When the signals from the outputs of the filter 4.1, ..., 4.p level Ug are exceeded, the threshold blocks 5.1, ..., Z.p work. At the same time, a rectangular pulse is formed at their output, the duration of which is equal to the time that the block 5.1 was in the activated state. This pulse arrives at the control input of the detector and allows the detector to measure the signal level at the output of the i-ro filter 4.1.

In addition, all the pulses from the outputs of blocks 5.1, ..., 5.n come to the input of the block 10 of the formation of a read pulse and a reset. At the same time, after the shortest of the pulses arriving at the input of the block 10, short pulses are generated at its outputs: first, on the bus, read a and after a short time At; (determined by the delay line included in block 10) - on the Reset bus.

With the appearance of a read pulse, the levels of the signals from the filters 4.1, ..., 4. p, measured in the peak detector, through the keys 7.1, ..., 7, p are fed to the input of the block 8 for the extraction of the two largest input voltages. After time t, the measurement. The information present on the PD is erased by a reset pulse.

These signals correspond to the two largest of the n output voltages of pi KOBbix detectors. Depending on the channel codes that entered the first and second inputs of block 11 from block 8, the corresponding weighting coefficients оС appear on output of block 11; and pj.

After the occurrence of the signals U and and the coefficients and / 3, at the input of block 9, it calculates the estimate t by formula (1). This estimate appears at the output of block 9, i.e. at the exit .

0

five

0

five

0

five

five

0

five

0

single pulse duration meter.

BUT

Estimate t, can be the value

 - C2. KV4F) Wash -. Uffi-il.

H- (S-.V1K ") y-oh.

 t,

l

The rating is determined by measuring the voltage in the channels most consistent with the pulse duration. This results in an increase in the noise immunity of the meter.

Claims (1)

Invention Formula A meter for the duration of single radio pulses containing a series-connected bandpass filter and detector, as well as n low-pass filters and a decisive block, characterized in that, in order to reduce the measurement error, n scale amplifiers and threshold blocks, as well as n series-connected peak detectors with keys and reset, the block of the two largest of the input voltages, the storage block AND, the n-input block of the read and reset pulse, the reset bus of which is connected, to the reset inputs of the peak detectors with a reset, the read bus is connected to the control inputs of the keys, and each input is connected to the output of each threshold block, each input of the n-input block to the two largest of the input voltages is connected to the output of each key, the first and the second outputs to the first and second inputs of the decision block, and the third and fourth outputs to the first and second inputs of the storage unit, the first and second outputs of which are connected to the third and fourth inputs of the decision block, the inputs of the scaler amplify Pins are combined and connected to the detector output, and the output of each large-scale amplifier is connected to the input of each low-pass filter, the output connected to the inputs of each threshold unit and each peak detector with a reset, while the control inputs of the threshold units are connected and connected to the bus voltage threshold and the output of each threshold unit is connected to the control input of each peak detector with a reset.