SU1250988A1 - Panoramic meter of frequency characteristics - Google Patents

Abstract

The invention relates to a radio measuring technique. It can be used in panopair in irocio-diagonal frequency response meters (IFC). The aim of the invention is to increase the speed and dynamic range of measurements of the frequency response and simplify its structures. Into a device containing an indicator 1, a generator 2, a transducer 3 of measuring information with a connected object of measurement, new connections have been introduced. Indicator 1 includes measuring converter 4, switch 5 channels, analog-1 converter 6, digital control computing device 7. Generator 2 includes tunable frequency generator 8, tunable multiplier 9 frequency, switch 10 subbands, output level detector 11, unit 12 I / O, block 13 digital-analog adjustment. This goal is achieved by introducing a preliminary calibration of the law of device tuning and setting the frequency for periodic frequency tuning taking into account the law of calibration, which reduces the design and technological requirements for the device nodes and thus damages their design. 1 il. (L SP 0 00 00

Description

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This invention relates to a radio metering technique and can be used in panoramic wideband frequency response meters (RFI) measurements of radio devices.

The circuit of the invention is to increase the fastness and dynamic range of measurements of the frequency response and simplify its design by introducing a preliminary calibration of the law of device tuning and setting the frequency during periodic frequency tuning taking into account the law of calibration, which reduces the design and technological requirements for the device nodes and thereby simplifies them construction

The drawing shows the structural scheme of the proposed IHC.

Panoramic PCh contains a ringed indicator 1, a generator 2 and a transducer 3 of measurement information with a connected measurement object 3-1. Indicator 1 includes a serially connected measuring transducer 4 (pi), a switch of 5 channels, an analog-to-digital converter (ADC) 6, and a digital control-calculating device (CCWC) 7. The generator 2 includes a series-connected generator 8 tunable frequency (VFD), tunable multiplier 9 frequency (UCH), 10 subband switch and output level detector 11, as well as input / output unit 12 (BVV), whose outputs are connected via data and control buses through the first block 13 digital-analogue the new tuning (BTsAP) to the inputs of the FPG 8 (one input for frequency tuning, the other for switching its circuits) and the control input of the switch 10 and through the second BTsAP input of the UF tuning 9. The first signal input of the switch tO through the UF 9 is connected to the first output of the FPG 8 tunable frequency signal from fj to 2f2. The second signal input of the switch 10 is connected to the second output of the frequency signal of the tunable frequency from f, to f, and, Third, the output of the VLT 8 with a signal of a tunable intermediate frequency

1250988

which are connected to the corresponding inputs - outputs of the central control system 7. From the central control unit 7 to the nodes of the generator 2 through the BVV 12, digital buses are connected via buses

S data, address and control pulse signals (device sampling, recording and reading of data information by selectable addresses in generator 2). These signals are for

 About the control of the functions of the generator 2, For the same buses, the CCTV 7 receives, through the BW 12 from the generator 2, information in digital form about the value of the frequency f d and the signals of the control mandates. In addition, the CCNT 7 also controls the operation of all nodes of the indicator 1, performs logical operations on the measurement process and on processing its results,

These are displayed on the screen of the CRT indicator 1 in digital and graphical forms. The BWB 12 composition includes a trigger frequency counter f, a bus driver for transmitting

25 data bus signals from the central control unit 7 on 1} data to the BTsP 13 and 14 and signals from the outputs of the frequency counter “y to digital control center 7”, as well as a decoder with a control circuit based on the standards of the integrated microcircuits. HLC 7 on control buses to BVV 12, BTsP 13 and 14. BTsAP 13 includes a data storage register with a digital-analog converter for generating AChF frequency tuning voltage 8 and a data storage register for transmission over the output bus BTNC 13

40 switching signals in HPS 8 and switch tO when switching frequency bands of oscillator 2, BTsAP 14 includes a data storage register with serially connected digital-to-analog converter and voltage-to-current converter for generating an electromagnet coil tuning current

50

53

a multiplier 9 and its frequencies, as well as a data storage register for switching circuits of a voltage to current converter in order to select a working harmonic of a multiplier 9, a THD 8 includes an electrically tunable oscillator that generates, for example, using a varicap in the -1/2 frequency range - f j. This generator is covered by a frequency tracking system.

linearly linked from f to 2f

pch

in the range

2

frequencies connected

with input BVV 12, other inputs-outputs

a multiplier 9 and its frequencies, as well as a data storage register for switching circuits of a voltage to current converter in order to select a working harmonic of a multiplier 9, a THD 8 includes an electrically tunable oscillator that generates, for example, using a varicap in the -1/2 frequency range - f j. This generator is covered by a frequency tracking system.

auto-tuning using a down-conversion frequency range fj / 2 - f2 to the frequency range f - fJ / 2 using a mixer and a fixed frequency generator. The tunable intermediate frequency signal, the auto-tuning system is connected by a linear function to the subband frequencies f, - f, / 2 and f, / 2 - f. A part of the frequency signal is supplied to the third output of the HPC 8 for measuring it with a frequency counter in the BVV 12 and transmitting the measurement result to the CCS 7. Frequency subbands f, - / 2 and. - fj in the GNP 8 are summed and the signal of the total frequency range f, - fj is fed to the second output of the GNP 8. The first output of the GNP 8 is given a double signal (using the frequency doubler) of the master oscillator in the frequency range 2 (2. Multiplier 9 is built on a diode with an accumulation of charge with a variable tunable ferrite filter on a gyromagnetic resonator. The resonant frequency of the UF filter 9 is tuned by a current from the BTsAP 14, which is supplied to the coil of the UC 9 electromagnet. ) c frequencies g Armonik n (where n 1, 2, 3,.,.) of signals fj - 2f2. Switch 10 subbands performed on pin diodes Under the influence of the switching signal from BTsAP 13 on command from the central control board 7 switch 10 connects to the generator output 2 signals with frequencies f, - fj or n (fj-If), the output level detector 11 is constructed according to known schemes. The sensor-converter 3 generates signals with a frequency of generator 2 with measurement information about the measured parameters of the object 3-1 and converts them without distorting the measurement information into signals of a fixed frequency converter tuning 4 1. The indicator composition, structure and compounds of the transmitter circuit 3 will depend on the type and character of the parameters of the measured object. For example, to measure the frequency characteristics of the modules of the reflection coefficients and transmissions of the passive quadripole, the sensor transducer can be implemented as a serial connection of the main channels of the directional drop taps.

reflected and transmitted waves with terminal matched load. The input of such a connection is connected to the output of the generator 2, and the secondary channels of all three directional couplers through the detector heads are connected separately to the inputs of the indicator 1. The connection of the reflected wave to the transmitted wave includes the object to be measured, PI 4 contains m channels ( three) amplification of low-frequency signals with information about the measured parameter of the object (coming from the outputs of the sensor-converter 3), normalizing their amplitude with the help of electrically controlled attenuators and detectors for the measurement of direct current measurement information. The outputs of the PI4 channels using a switch of 5 channels made on the microcircuits of electrically controlled integrated switches are connected in a certain sequence to the signal input of the A / D converter 6. A / D converter 6 converts the DC signals with the measurement information into digital information signals.

The control of the PI4 functions (amplitude rationing in channels) by switch 5 (channel selection) and ADC 6 (organization of data conversion and reading of information) is carried out by HLTC 7 via control buses.

Panoramic IFH works as follows.

The operator from the front panel of indicator 1 (not shown in the drawing) specifies the frequencies of the tuning band: the initial end of the circuit. Consider the case when

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nf, and f itoh 2nf g. After setting the values of f using the BVV 12 blocks, the BTsAP 13, taking into account the information about the frequencies, sets the frequency tuning limits at the first output of the VFG 8 so that its value changes from 2f2 to f2. Then, the CCNC 7 performs the calibration of the law of the LF 9 adjustment as follows.

At the first output of the VFG 8, TCU 7 with the help of BVV 12 and BTsAP 13 sets the frequency 2f, j. Then, the UHC 7 with BBI 12 supplies to the inputs of the BTsAP 14 a signal for selecting the first harmonic of the multiplier 9 and the maximum data code for setting the resonant frequency, multiplier 9 above 2f. Then, the data code at the inputs of the BCLAA 1A is successively reduced by decreasing the tuning frequency f c, which approaches the frequency F 1 H 8 2f. The output voltage of the detector t1 at the same time changes according to the law of the resonant curve of the filter multiplier 9. This voltage is due to a command from the central control circuit 7 goes through the switch 5 channels and the ADC 6 to the central control system 7 for determining and storing the data code. In the mix of which the multiplier 9 is set to the maximum value of the fundamental resonance at the frequency 2f. Then, the calibrations described above repeat at the frequency f The set values in the interval Zfj) and the code Mits are remembered. The calibration procedure is performed on all the working harmonics n of the multiplier 9 that fall into the operator-adjusted tuning band {,, (, ". Then, the B codes are set and memorized the frequency settings of the multiplier 9 to the points of the frequency of the fader 8 f, and its harmonics in the interval n (fj-2f2). At the same time, the law of rearrangement of multipliers 9 in the frequency sections 45, ..., nf2-2nf2 is linear. The codes B to adjust the multiplier 9 to the frequencies nf are calculated by the formula:

I n honey COP

(n max ® MIN I,,, 1 +. ntr- «tjV

(

 2Bn iin (n max-pmin) tfHs bfl «ax

At this, the calibration of the frequency tuning law of the multiplier 9 ends and a periodic frequency tuning of the oscillator 2 begins by periodically setting a predetermined number of frequency points uniformly distributed in the band f? - f.

The setting of each point of the nfy frequency is performed as follows.

HLCH 7 feeds with the aid of the BWB 12 first the data code to the BTsP 13, corresponding to the frequency of the GTP 8i, then HLCH 7 with the help of the BWI 12 feeds the B data code B calculated during the calibration and the multiplier 9 is tuned to resonance at the frequency nf the more accurate more

j

About 5 0 5 0 5

five

Frequencies were chosen at a certain law of its restructuring. The signal of this frequency is fed to the input of the object and the transducer 3 generates signals with information about the measured parameters with the tuning frequency of indicator 1. These signals are amplified, normalized, detected in PI 4, passed through the tator 5, digitized into The A / D converters 6 and after 1-digit processing in the CCTV 7 are displayed on the screen of the indicator 1 in the form of curves and digital signals.

Claims (1)

Invention Formula A panoramic frequency response meter comprising a ring-connected indicator, a generator and a transducer of measuring information with a connected measurement object, the indicator including successively connected measuring transducer, a channel switch, an analog-to-digital converter and a digital control-computing device, outputs the control of which is connected to the inputs of the control of the analog-digital converter, the channel switch and the measuring converter, and the generator includes a tunable frequency generator connected in series, a frequency multiplier tunable, a subband switch whose output is the generator output, and an output level detector, as well as an input / output unit whose inputs are the generator input and the outputs are connected through the first block digital-to-analog tuning to the inputs of the tunable frequency generator and the control input of the subband switch and, through the second block of the digital-to-analog tuning, to the tuning input of the tuning frequency multiplier, the second signal input of the subband switch is connected to the second output of the tunable frequency generator, the third output of which is connected to the second input of the I / O unit, which, in order to increase the speed and dynamic range of the frequency meter measurement and simplify its design, the output of the output level detector is connected to one of the inputs of the switch of the indicator LEDs.