SU1587577A1 - Method of measuring profile of inner diameter of outer tubular conductor of coaxial cable - Google Patents

Abstract

This invention relates to a measurement technique. The purpose of the invention is to improve the measurement accuracy. The line including the sample under study, the inner conductor with insulation, the reference samples of the coaxial cable and the reference segment of the outer tubular conductor is probed twice using an OTDR. In this case, the reference segment of the outer tubular conductor is placed on the inner conductor, first between one and then between the other reference sample of the coaxial cable and the end of the sample under study. After that, the obtained reflectograms are compared and the true profile of the sample is isolated. 1 il.

Description

This invention relates to a measurement technique and can be used to measure a profile of precision semi-rigid coaxial cables with a tubular outer conductor.

The purpose of the invention is to improve the measurement accuracy by reducing the error due to instability of the parameters of the inner conductor.

The method is implemented as follows.

Reference samples of coaxial cable are attached to the test image from two ends, representing the same type of cable as the test sample with an insulated internal conductor, and then between one end of the test sample and the reference sample of the coaxial cable, the reference piece is installed on the internal conductor with insulation.

the outer tubular conductor, probes the resulting line with a reflectometer and records the reflectance reflectance.

Then, the reference length of the outer tubular conductor is installed on the inner conductor with the insulation between the other reference sample of the coaxial cable and the other end of the test sample, marking the test sample relative to the inner conductor with the insulation for the length of the reference length of the outer tubular conductor, secondly probe the obtained line with an OTDR and A reflectance trace is recorded.

Then the obtained reflectograms are compared and the profile of the inner diameter of the outer tubular conductor is selected.

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by subtracting one of the other ordinates of the corresponding portions of the trace.

The drawing shows a block diagram of the device that implements the method.

The device contains reference samples.

1 coaxial cable, reference length

2 external conductor, located on the internal conductor 3 with the isolation of the test sample of the coaxial cable, reflectometer 4, the input of which is connected to the internal conductor 3, two-level comparator 5 connected to the output of the reflectometer 4, 6 clock pulses, switch 7, analog-to-digital converter ( ADC 8, whose information input is connected to the second output, reflectometer 4, key 9, whose information input is connected to the output of ADC 8, memory blocks 10 and 11, whose inputs are connected to the outputs of key 9, and after formatively connected unit 12 of the difference, accumulating the adder 13 and the recorder 14.

The device works as follows.

An inner conductor 3 is inserted into the test specimen, on which reference segment 2 is placed, and then is attached to the ends of the test specimen.

with reference samples 1 coaxial cable.

The obtained line is probed by the reflectometer 4 and at its first output we obtain the reflectogram of the impedance, which is fed to the information input of the ADC 8.

At the same time, the linearly increasing voltage from the output of collector 4 goes to the comparator 5, which, when triggered to the lower level, starts the generator 6, opens the key 9 on the first output and switches the switch 7 to the position when the pulses from the generator 6 arrive at the input of the unit 10. These clock pulses convert analog information into a digital ADC 8 and write it to memory block 10.

When the linear-rising voltage of the upper level OTDR 4 is reached, unit 5 stops the generator 6, the end of the first measurement cycle is fixed. Then remove the reference segment 2, shift the sample under test for the length of the reference segment 2, and the reference segment 2 is mounted on the inner conductor

3 from the other end of the sample. Reference samples 1 are still attached to the ends of the test sample. Line is again probed with an OTDR 4.

5 Similarly, information is recorded in memory block 11.

When the linear-rising voltage of the upper level OTDR 4 is reached, the switch 7 transmits clock pulses from the generator 6 to the inputs of the blocks

 11 and 13. At each clock pulse in block 12, the values of wave resistance are subtracted, in block 13, the value of the measured profile is selected, which is recorded by the recorder 14.

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Claims (1)

Invention Formula A method for measuring the internal diameter profile of the outer tubular conductor of a coaxial cable, which consists in inserting an inner conductor with an insulation into the sample under test, using the reflectometer to probe the resulting line and record the reflectogram of the resulting impedance different 5 in order to improve the measurement accuracy, reference samples of coaxial cable are attached to the test sample from two ends, then between the end of the test sample and the reference sample of coaxial cable an internal piece of outer tubular conductor is installed on the internal research institute with insulation t sounding with the reflectometer of the obtained line and record the reflectance of the wave resistance, then the reference segment of the outer tubular conductor is installed on the internal windows explorer with insulation between the other reference samples of the coaxial cable and the other end of the test sample, wherein the moving analyzed Q a sample relative to the inner conductor, re-probe the obtained line with a reflectometer and record the reflectance of the impedance, then compare the resulting reflectance of the impedance and extract the profile of the inner diameter of the outer coaxial cable by subtracting the coordinates of the corresponding portions of the reflectogram. / L.