Method for calibrating a test rig

Patent metadata

Field	Value
Publication number	US-9921287-B2
Application number	US-201414914181-A
Country	US
Kind code	B2
Filing date	Aug 25, 2014
Priority date	Aug 26, 2013
Publication date	Mar 20, 2018
Grant date	Mar 20, 2018

Abstract

A method for calibrating a test apparatus, having a first and a second directional coupler, for gauging a two-port test object that has a first port and a second port in a calibration plane, wherein for the purpose of calibrating the test apparatus a vectorial network analyzer having a 1st-6th test port is connected to the first and second ports in the calibration plane such that the first and second test ports are connected to respective port in the calibration plane, the third and fourth test ports are connected to the first directional coupler and the fifth and sixth test ports are connected to the second directional coupler via a respective waveguide for electromagnetic waves. For different calibration standards, scatter parameters are determined for each desired frequency point. For the different calibration standards, corrections to the scatter matrix are made in order to obtain a corrected scatter matrix. The scatter parameters of the corrected scatter matrix are used to determine terms for error matrices.

First claim

Thus, having described the invention, what is claimed is:

1. A method for calibrating a test apparatus, having a first and a second directional coupler, for testing a two-port test object (DUT—Device Under Test), which has a first port and a second port in a calibration plane;
wherein for the purpose of calibrating the test apparatus a vectorial network analyzer (VNA) having a first, a second, a third, a fourth, a fifth and a sixth test port is connected to the first and second ports in the calibration plane such that the first test port is connected to the first port in the calibration plane, the second test port is connected to the second port in the calibration plane, the third and fourth test ports are connected to the first directional coupler and the fifth and sixth test ports are connected to the second directional coupler via a respective waveguide for electromagnetic waves;
wherein at the first test port an electromagnetic wave a 1 runs out in the direction of the first port in the calibration plane and an electromagnetic wave b 1 runs in from the direction of the first port in the calibration plane;
wherein at the second test port an electromagnetic wave a 2 runs out in the direction of the second port in the calibration plane and an electromagnetic wave b 2 runs in from the direction of the second port in the calibration plane;
wherein at the first port in the calibration plane an electromagnetic wave a DUT,1 runs in from the direction of the first test port and an electromagnetic wave b DUT,1 runs out in the direction of the first test port;
wherein at the second port in the calibration plane an electromagnetic wave a DUT,2 runs in from the direction of the second test port and an electromagnetic wave b DUT,2 runs out in the direction of the second test port;
wherein between the first test port and the first port in the calibration plane a component of the wave a 1 is coupled out by the first directional coupler as a Mess,1 and fed to the third test port of the VNA;
wherein between the first test port and the first port in the calibration plane a component of the wave b 1 is coupled out by the first directional coupler as b Mess,1 and fed to the fourth test port of the VNA;
wherein between the second test port and the second port in the calibration plane a component of the wave a 2 is coupled out by the second directional coupler as a Mess,2 and fed to the fifth test port of the VNA;
wherein between the second test port and the second port in the calibration plane a component of the wave b 2 is coupled out by the second directional coupler as b Mess,2 and fed to the sixth test port of the VNA;
wherein in order to calibrate the test apparatus, instead of the DUT at least three different calibration standards are arranged in the calibration plane;
wherein for each calibration standard K and for each desired frequency point of a frequency f of a 1 or a 2 scatter parameters S xy,K,f , where x=1, 2, 3, 4, 5 or 6 and y=1 or 2, are determined between the y-th and the x-th test port of the VNA for the calibration standard K and the frequency f is determined from the known values a 1,K,f and a 2,K,f as well as from the measured values b 1,K,f , b 2,K,f , a Mess,1,K,f , b Mess,1,K,f a Mess,2,K,f , b Mess,2,K,f , whereby

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Assignees

• Rosenberger Hochfrequenztechnik Gmbh & Co Kg

Inventors

• Zietz Christian
• Haerke Dominic

Classifications

• G01R31/318357

  Simulation (computer simulation of digital circuits G06F30/3308) · CPC title

• G01R27/28

  Measuring attenuation, gain, phase shift or derived characteristics of electric four pole networks, i.e. two-port networks; Measuring transient response (in line transmission systems H04B3/46) · CPC title

• G01R31/2848

  using simulation · CPC title

• G01R31/31816

  Soft error testing; Soft error rate evaluation; Single event testing · CPC title

• G01R35/005 Primary

  Calibrating; Standards or reference devices, e.g. voltage or resistance standards, "golden" references (G01R33/0035, G01R35/002 take precedence) · CPC title