SU1613967A1 - Apparatus for measuring parameters of frequency-modulated harmonic signals - Google Patents

Abstract

The invention relates to a measurement technique and can be used to measure the instantaneous frequency of frequency-modulated harmonic signals and its deviation from the nominal value. The aim of the invention is to expand the functionality of the device. The device provides detection of the deviation of the instantaneous frequency of the harmonic signal according to the mathematical expression given in the description of the invention, and contains analog-to-digital converter 1, shift registers 2, 3 and 4, adders 5, 13, pulse generator 6, division unit 7, unit 8 multiplying by two, an arc-sine transducer 9, a multiplication unit 11, blocks 10 and 12 of memory. 1 il.

Description

This invention relates to a measurement technique and is intended to measure the instantaneous frequency of frequency-modulated (FM) harmonic signals and its current deviation from the carrier frequency.

The purpose of the invention is to expand the functionality of the device due to the possibility of measuring the frequency deviation of its carrier.

The drawing shows an electrical block diagram of a device for measuring parameters of FM harmonic signals

The device contains an analog-to-digital converter 1, step 2, second 3 and third 4 shift registers, adder 5, pulse generator 6, dividing block 7 with zero check, block 8 multiplying by two, arc-sine converter 9, first block memory 10, multiplication unit 11, second memory unit 12 additional amount

torus 13.

Output A1Sh 1 is connected via serially connected first, second and third shift registers 2-4 to the first input of the adder 5, the second input of which is connected to the output of the first shift register 2 The output of the adder 5 is connected to the first input of the dividing unit 7 with a zero check, the second input which is connected through the multiplication unit 8 by two with the output of the second shift register 3 o. The output of the division unit 7 with zero check is connected via the arc-sine converter 9 to the first input of the multiplication unit 11, the second input of which is connected to the output of the second unit and 12 memory. The first input of the additional adder 13 is connected to the output of the multiplier 11, and the second input to the output of the first luster 10 of the memory. The output of the generator 6 impulses connected to the controls of the inputs of the registers 2-4 shift

The device works as follows

Selects the polling frequency of the input signal f 4f

„.I-o- where f and -“ is the frequency. In memory units Yu, the values 1 / 2pTz are recorded and, respectively, the FM harmonic signal is fed to the analog input ASCH11, which produces

period Td converts the instantaneous voltage values into a T1 code code. This code enters the input of the first shift register 2 and sequentially fills the second and third shift registers 3 and 4. Thus, in the set mode. In shift register 4, the code V .. is located, in shift register 3, the code Vj., In register 2, the code Vj, where Vj, V, V are instantaneous voltages in moments of time t, t, ti represented in the digital code. The contents of the first register 2 of shift 5 (g) and the third register 4 of shift (V.) are summed in adder 5 and the result is fed to the first input (divisible) of dividing unit 7 with a check for Zero The content of the second Q register 3 shift is fed through the block 8 multiplied by two to the second input (dividing) of the dividing unit 7 with the check for zero. Thus, at the output of dividing block 7 with checking for 5 by zero, a code is obtained equal to

YilYi which arrives at the entrance

arc cosine converter 9 "At the output of the arc cosine converter, Q L 9, a code is obtained equal to

35

40

arccos () that arrives on

first input - multiplication unit 11 The second input of multiplication unit 11 receives the code recorded in the first memory unit 10. Thus, at the main output of the device, we have the code of the instantaneous frequency of the harmonic signal. The same code arrives at the first input of the additional adder 13, the second input of which receives the code from the output of the second memory block 12. Thus, 45 at the output of the additional adder 13 we have the code of the current frequency deviation Afo further, with the arrival of the next clock pulse from the generator output 6 pulses through the period-TD, information is shifted in the shift registers, and at the output of the ADC 1 there appears a digital code corresponding to the next instantaneous value of the voltage, which is recorded in the first shift register 2, and the device starts to calculate the next value of the instantaneous frequency of the signal and the current frequency deviation

50

55

516

Claims (1)

Invention Formula A device for measuring parameters of frequency-modulated harmonic signals, containing a series-connected pulse generator, an analog-to-digital converter, first, second, and third shift registers, an adder, the second input of which is connected to the output of the first shift register, while the control inputs of the shift registers are connected to the output of the pulse generator, the input of the analog-to-digital converter is connected to the input of the device, characterized in that, in order to expand the functional possibilities due to instantaneous rejection of an hour3967 In addition, serially connected dividing unit, arc-sine converter, multiplication unit and additional adder, as well as the first and second memory blocks and the multiplying unit by two, the input of which is connected to the output of the second shift register, and the output are connected to the control input the division block, the input connected to the output of the adder, the output of the additional adder. - with an additional output of the device, the output of the second memory block is connected to the second input of the additional adder, the output of the first memory block is connected to the second input of the multiplication unit, the output of which is connected to the output of the device. ten 15