EP1305646A1 - Procede et dispositif de calibrage - Google Patents

Procede et dispositif de calibrage

Info

Publication number
EP1305646A1
EP1305646A1 EP01956338A EP01956338A EP1305646A1 EP 1305646 A1 EP1305646 A1 EP 1305646A1 EP 01956338 A EP01956338 A EP 01956338A EP 01956338 A EP01956338 A EP 01956338A EP 1305646 A1 EP1305646 A1 EP 1305646A1
Authority
EP
European Patent Office
Prior art keywords
analog signal
calibrated
signal
data
generating
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP01956338A
Other languages
German (de)
English (en)
Inventor
Helmut Pflaum
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Credence SZ Systems GmbH
Original Assignee
SZ Testsysteme AG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by SZ Testsysteme AG filed Critical SZ Testsysteme AG
Publication of EP1305646A1 publication Critical patent/EP1305646A1/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/28—Testing of electronic circuits, e.g. by signal tracer
    • G01R31/2832—Specific tests of electronic circuits not provided for elsewhere
    • G01R31/2836—Fault-finding or characterising
    • G01R31/2839—Fault-finding or characterising using signal generators, power supplies or circuit analysers
    • G01R31/2841—Signal generators

Definitions

  • the invention relates to a method for generating a calibrated, periodic analog signal according to the preamble of claim 1, a method for determining calibration data for a signal path, a method for measuring the response of an electronic test object to a periodic analog signal and corresponding devices.
  • electronic test object is to be understood to mean any kind of electronic components and electronic systems, in particular integrated electronic circuits and systems (also called ICs) and electronic components. These are often summarized in the professional world by using the English generic term “device under test” ("DUT" for short).
  • DUT device under test
  • test signals can be any signals, but periodic signals in particular are single-tone or multi-tone signals.
  • the invention has for its object to provide a method for generating a calibrated, periodic analog signal, a method for determining calibration data for a signal path, a method for measuring the response of an electronic device under test to a periodic analog signal and corresponding devices that the interference components reduced to a minimum, or which make it possible to reduce the effects of the interference components to a minimum.
  • relevant frequency components of an analog, periodic output signal of a signal generator which generates the output signal on the basis of predetermined digital data are measured by means of a suitable measuring device.
  • a correction is determined for the digital data on which the analog signal is based, which are then changed.
  • the digital data changed via the correction values are converted again into an analog test signal in the signal generator and, in turn, examined via the measuring device with regard to any remaining interference components.
  • This calibration process is repeated until the signal generator generates an output signal in which the interference components at all frequencies in question are reduced to below a predetermined limit value, for example to the area of the noise.
  • the measures according to the invention thus make it possible to adapt an output signal of a generator which is originally faulty in such a way that a test object can be supplied with a periodic analog signal which is practically free of interference components.
  • the hardware expenditure for measuring the interference components of the output signal is low if the amplitudes of the interference components occurring at the relevant frequencies are recorded using a frequency-selective voltmeter or a similar measuring device.
  • the phase of the interference components occurring at the relevant frequencies cannot be determined using a frequency-selective voltmeter, it is possible to determine the respective phase by iteration.
  • This iteration includes, for example, that a correction phase is first selected and that the digital data are changed as if the output signal were superimposed in phase opposition with the selected correction phase and the correction amplitude determined via the voltmeter.
  • the phase of the interference components can be determined more precisely from the output signal modified by the change in the digital data.
  • the correction phase is specifically changed until the interference components are below the predetermined limit value - for example the noise limit.
  • a preferred procedure for determining the phase of the interference components at a specific frequency is the so-called binary search. Sections of the semicircle of the possible 180 ° hidden phase shift are halved until the applicable phase has been determined with sufficient accuracy. For example, first a correction phase of + 90 ° accepted and applied to the signal as described above. From the resulting signal it can be seen whether the phase of the interference components lies in the quadrant from 0 ° to + 90 ° or in the quadrant from 0 ° to -90 °. The quadrant in question is again halved, ie one of two possible correction phases is selected and applied, namely + 45 ° or -45 °.
  • one of the four correction phases ⁇ 22.5 ° and + 67.5 ° is selected and applied. In this way, the process continues until the correct correction phase has been determined with sufficient accuracy.
  • Such an iterative method also has the advantage that it can possibly track possible subsequent changes in the interference components due to the change in the input data or the signal applied.
  • Signal normally does not cause any significant changes in the interference components outside the local frequency range, but it is possible to carry out a frequency-local calibration of the respective frequency components of the signal in parallel, in part in parallel or in sequence.
  • the test signal emitted by the generator can be calibrated using the procedure described above. Since an A / D converter for processing the signal emitted by the device under test can also cause corruption, it is also advantageous in the case of a test signal optimized in the sense described above if calibration data relating to the A / D converter and the other signal path are determined, the further processing of a transmitted or converted signal can be used to compensate for the falsifications caused.
  • the ideal analog signal free of interference components and whose frequency spectrum is known, is applied to the input of the A / D converter.
  • the relevant frequency components of the resulting, faulty digital signal are calculated and compared with the known frequency component values for the purpose of determining calibration data.
  • the determined calibration data are preferably stored in a memory.
  • the digitized response signals obtained during the test of the device under test are then corrected with these stored calibration values, so that the interference from the A / D converter (digitizer) and the other signal path are also reduced to a predetermined level, for example to the level of noise.
  • FIG. 1 shows a block diagram of a measuring arrangement according to the invention for measuring the reaction of an electronic test object to a periodic analog signal
  • FIG. 2 shows a flow diagram of a calibration method for a generator of the measuring arrangement from FIG. 1;
  • FIG. 3 shows a flow diagram of a calibration method for a digitizer of the measuring arrangement from FIG. 1;
  • Figure 4 shows the frequency spectrum of a signal with interference components and
  • Figure 5 shows the frequency spectrum of a signal calibrated according to the inventive method.
  • FIG. 1 shows a block diagram of a measuring arrangement 1 according to the invention for measuring the reaction of an electronic device under test 12, for example an xDSL (digital subscriber line) from telecommunications, to a periodic analog signal.
  • the measuring arrangement 1 has a signal generator 2 (arbitrary wave generator), indicated by dash-dotted lines, via which digital data connected to its input 4 can be converted into an analog test signal which is used for testing the test object 12.
  • the signal generator 2 essentially consists of a D / A converter to which additional components 8 for signal processing, such as amplifiers and filters, are assigned. Furthermore, the reference number 10 denotes components, such as, for example, plug sockets, line lengths, parasitic capacitors, etc.
  • the quality of the test signal depends on the components of the D / A converter, the quality of the components 8 and the components 10. In particular due to the last-mentioned components 8, 10, the signal, for example given digitally as a multi-tone signal, after its digital-to-analog conversion and transmission contains, in addition to the multi-tone frequencies, further interference components which can lead to a falsification of the measurement result when testing the test object 12.
  • the digitizer 14 indicated in FIG. 1 essentially consists of an A / D converter 18 and other components 20 for signal processing, such as dividers or filters, and the aforementioned parasitic and, if appropriate, external components 22, which can influence the signal quality.
  • an ideal, periodic analog signal which is not subject to interference components, is first generated at the output of the signal generator 2, the frequency spectrum of which must be known at least for the frequencies in question.
  • This ideal analog signal is - as indicated by dashed lines in FIG. 1 - applied directly to the input of the digitizer 14 and converted into a digital signal via the A / D converter 18, the relevant frequency components of which are calculated, for example, using a Fast Fourier transformation.
  • calibration values are determined, by means of which the influence of measurement hardware-related interference components on measurements subsequently carried out via the measurement arrangement 1 can be greatly reduced.
  • FIG. 2 shows a flowchart of a method for calibrating the signal generator 2 designated by 2 in FIG.
  • a desired signal is calculated or specified via an input unit 23 and in one via the signal path S1, S2 indicated in FIG.
  • Signal memory 24 (signal RAM) as so-called digital Waveform data stored.
  • This digital data which ideally corresponds to the waveform of the desired signal, is converted according to the signal sequence S3, S4, S5, S6 into an analog output signal which is made available at the output 26 of the signal generator 2.
  • the conversion of the desired signal data stored in the signal memory 24 takes place via the D / A converter 6.
  • the processing of the analog signal resulting from the conversion takes place via the filter and amplifier designated with the reference number 8.
  • the other components of the signal generator 2 which influence the signal quality are summarized by the block 10.
  • the output signal appearing at the output 26 of the signal generator does not correspond to the ideal of a signal which precisely has the waveform predetermined by the digital data, but is overlaid with inevitable noise and interference components which can be compensated for by the calibration method described below.
  • the target signal programmed via the input unit 23 is a two-tone signal with two frequency components F1 and F2, the target signal being characterized by the phase and amplitude of the two frequency components F1 and F2.
  • the desired signal characterized by the frequency components F1, F2 is superimposed by noise 30 and further interference components.
  • These interference components can have a considerably larger amplitude than the noise, so that the output signal at the output of the signal generator 2 does not have the required quality in the case of high quality requirements.
  • the faulty output signal appearing at the output 26 of the signal generator 2 is measured at certain frequencies using a frequency-selective voltmeter 32 or a similar suitable measuring device.
  • the aim of this measurement is to determine the amplitude and phase of the interference components of the relevant frequency components of the output signal. Only the amplitudes of the interference components shown in FIG. 4 can be detected via the frequency-selective voltmeter 32, so that iterative methods have to be used to determine the phase of the interference component.
  • the measurement signal S8 detected for each relevant frequency component via the frequency-selective voltmeter 32 is transmitted via a
  • Calibration unit 34 processes, which on the basis of this measurement signal S8 generates a so-called frequency bin, which for the respective frequency comprises the correction amplitude detected by the selective voltmeter 32 and a selected cocculture phase.
  • the content of these frequency bins generated by the calibration unit 34 for each relevant frequency component serves as the basis for the calculation of correction data which, in the step denoted by reference numeral 36, corresponds as digital signal data S9 "in opposite phase" to the current waveform data present at the input of the signal generator 2 added and stored in the signal memory 24.
  • This new, corrected waveform data is then transmitted in the manner described above via the signal paths S3, S4, S5, S6 are converted into an analog signal appearing at the output 26, which in turn is measured via the frequency-selective voltmeter 32.
  • the measured values supplied by the frequency-selective voltmeter 32 are then used by the calibration unit 34 to update the frequency bins with a new correction phase and, if necessary, a new correction amplitude. This loop is run through until a suitable correction phase and correction amplitude have been determined for each frequency component, which allow the interference component to be canceled out below a predetermined limit level.
  • the waveform data stored in the signal memory 24 are changed by means of the correction amplitudes and correction phases measured or iteratively determined via the voltmeter 32 until the interference components in question of the analog signal generated by the signal generator 2 on the basis of the waveform data are below a predetermined limit value, for example below the level of noise are reduced.
  • This calibration process must be carried out separately for each frequency component.
  • the calibration process can be described as sequential, partly parallel or entirely parallel.
  • the measurement of the frequency components and determination of the frequency bins can be determined in parallel, partially in parallel or successively for all frequency components in each iteration. This results in a lot of freedom when implementing the device according to the invention with regard to the opposing design criteria of speed and hardware expenditure.
  • the interference components at the frequencies 2 ⁇ Fl-F2; 2 X F2 - Fl; 2 X F2; 2 x F2 + Fl and 2 X Fl + F2 are compensated up to the noise limit.
  • the interference components occurring at the frequency 2 ⁇ Fl were not calibrated out. Accordingly, a frequency bin comprising a correction amplitude and a correction phase was neither determined for these interference components, nor were changes made to the waveform data which would have led to a reduction in the interference components occurring at the frequency 2 ⁇ Fl in the output signal resulting from the waveform data.
  • the calibrated analog signal according to FIG. 3 occurring at the output 26 is applied to the input of the digitizer 14 via the signal path S10.
  • This ideal, analog signal is then converted via the signal path Sll, S12, S13, ie by means of the A / D converter 18, the additional signal processing components 20 (filter, divider, etc.) and the external and parasitic components 22 into a digital signal and im State memory 38 of digitizer 14 is stored.
  • This digital signal is passed to a signal processing processor 40, which uses the digital signal to calculate the frequency spectrum of the digital signal, which in turn contains interference components, for example by means of a Fast Fourier transform.
  • the frequency spectrum of the digital signal is displayed via a large number of frequency bins (amplitude, phase), which reflect the individual frequency components.
  • This non-calibrated data represented by block 42 is tapped via signal path S16 and compared in the comparison step identified by reference numeral 44 for each frequency component in question with the known frequency spectrum of the desired signal, also represented in the form of frequency bins.
  • the difference between the corresponding contents of the corresponding frequency bins of the known frequency spectrum of the desired signal and the non-calibrated data 42 is stored in a calibration memory 46 for each frequency component.
  • These calibration data (phases, amplitude) stored in the calibration memory 46 are fed to a calibration software 48 which is able to later correct frequency bins determined by the signal processing processor 40, for example by means of FFT analysis, in such a way that the interference components are reduced to a tolerable size.
  • the calibrated test signal generated by the signal generator 2 is then applied to it and the resulting response signal is converted into a digital signal via the digitizer 14.
  • the frequency signal of the digital signal superimposed with interference components is broken down by the signal processing processor 40, which in turn is revised by the calibration software 48 on the basis of the calibration data stored in the calibration memory 46 in such a way that all interference components detected during the calibration and caused by the digitizing signal path, for example harmonic components Harmonics can be largely distinguished from the true signal components and eliminated
  • a method and a device for generating a calibrated periodic analog signal with predetermined frequency components are disclosed. According to the invention, uncalibrated digital data are calculated using the predetermined frequency display, this data is converted into an analog signal, parameter values of the output signal are recorded and, if the parameter value exceeds a limit value, a correction value for the digital data is determined.

Landscapes

  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Analogue/Digital Conversion (AREA)

Abstract

L'invention concerne un procédé et un dispositif servant à générer un signal analogique périodique calibré avec des taux de fréquence prédéfinis. Selon l'invention, des données numériques non calibrées sont calculées à partir des taux de fréquence prédéfinis, ces données sont converties en un signal analogique, des valeurs de paramètre du signal de sortie sont enregistrées et, si la valeur de paramètre dépasse une valeur limite, une valeur de correction des données numériques est déterminée.
EP01956338A 2000-08-04 2001-07-18 Procede et dispositif de calibrage Withdrawn EP1305646A1 (fr)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE10038865 2000-08-04
DE2000138865 DE10038865A1 (de) 2000-08-04 2000-08-04 Kalibrierverfahren
PCT/DE2001/002698 WO2002012910A1 (fr) 2000-08-04 2001-07-18 Procede et dispositif de calibrage

Publications (1)

Publication Number Publication Date
EP1305646A1 true EP1305646A1 (fr) 2003-05-02

Family

ID=7651852

Family Applications (1)

Application Number Title Priority Date Filing Date
EP01956338A Withdrawn EP1305646A1 (fr) 2000-08-04 2001-07-18 Procede et dispositif de calibrage

Country Status (3)

Country Link
EP (1) EP1305646A1 (fr)
DE (1) DE10038865A1 (fr)
WO (1) WO2002012910A1 (fr)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102654771B (zh) * 2012-05-16 2014-03-26 电子科技大学 一种模拟通道的自动校准方法及系统

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5955523A (ja) * 1982-09-24 1984-03-30 Advantest Corp デジタルスペクトルアナライザ用信号発生器
US4637020A (en) * 1983-08-01 1987-01-13 Fairchild Semiconductor Corporation Method and apparatus for monitoring automated testing of electronic circuits
US4677581A (en) * 1985-05-30 1987-06-30 Allied Corporation Multichannel, self-calibrating, analog input/output apparatus for generating and measuring DC stimuli
US4998217A (en) * 1989-05-01 1991-03-05 Motorola, Inc. Sweep generator linearization system and method
US5039872A (en) * 1989-09-28 1991-08-13 The United States Of America As Represented By The Secretary Of Commerce Digitally synthesized audio frequency voltage source
JPH03296308A (ja) * 1990-04-13 1991-12-27 Advantest Corp 波形発生器
DE69100204T2 (de) * 1991-11-11 1994-01-13 Hewlett Packard Gmbh Einrichtung zur Erzeugung von Testsignalen.
US5642300A (en) * 1996-01-26 1997-06-24 Rotek Instrument Corp. Precision voltage/current/power source

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO0212910A1 *

Also Published As

Publication number Publication date
DE10038865A1 (de) 2002-02-14
WO2002012910A1 (fr) 2002-02-14

Similar Documents

Publication Publication Date Title
DE102013200033B4 (de) Verfahren und System zur Bestimmung von Streuparametern eines frequenzumsetzenden Messobjekts
DE69002233T2 (de) Vorrichtung und verfahren zur eichung eines fühlersystems.
EP1960797B1 (fr) Procede de mesure du coefficient de bruit d'un objet de mesure au moyen d'un analyseur de reseau
DE10015384A1 (de) A/D-Umwandlungsvorrichtung, Eicheinheit und Verfahren hierfür
DE69122404T2 (de) A/d oder d/a wandler, a/d und d/a wandlersystem und verfahren zur eichung dieses systems
DE102006013192A1 (de) Topologieunabhängiges Kalibrierungssystem
DE112008002111T5 (de) Messgerät, Prüfgerät und Messverfahren
DE102009011795A1 (de) Synthesizer mit einstellbarer, stabiler und reproduzierbarer Phase und Frequenz
CH630179A5 (en) Method for automatic zero-point and calibration correction in an electronic kilowatt/hour meter
DE102011011978A1 (de) Verfahren und Vorrichtung zur gleichzeitigen Ermittlung des Amplituden- und Phasenrauschens eines Messobjekts
WO2003102610A2 (fr) Procede et dispositif de detection dans le domaine frequentiel en fonction d'une mesure dans le domaine temporel
DE102005032982B4 (de) Verfahren und Vorrichtung zur Analog-Digital-Wandlung eines Eingangssignals
EP1131643B1 (fr) Procede de correction de l'affaiblissement de ligne fonction de la frequence et de la longueur dans le cas de mesures par reflectometrie en domaine frequentiel effectuees sur des cables haute frequence
DE69026212T2 (de) Wechselstromvorrichtung zum Prüfen eines IC-Testgerätes
EP1305646A1 (fr) Procede et dispositif de calibrage
DE102020212329B4 (de) Verfahren zum Testen eines Sensors und elektronische Schaltung
DE102020208306B4 (de) Verfahren und Vorrichtung zum Testen einer elektronischen Komponente mithilfe von Maschinenlernverfahren
DE102007005688A1 (de) Anregungssignalgenerator für verbesserte Genauigkeit von modellbasiertem Testen
DE10315372B4 (de) Verfahren und Vorrichtung zum Bereitstellen eines Messsignals und Vorrichtung zur Erfassung einer elektromagnetischen Störung
DE102020123859A1 (de) Zeitmessung eines taktbasierten Signals
DE10302362B4 (de) Verfahren und Vorrichtung zum Bestimmen einer Rauschgröße eines elektronischen Meßobjektes
DE102012208405A1 (de) Messgerät und Verfahren zur verbesserten Abbildung von Spektralverläufen
DE10024085C1 (de) Verfahren zur Korrektur der frequenz-und längenabhängigen Leitungsdämpfung bei TDR-Messungen an Hochfrequenzkabeln
DE102008004263B4 (de) Analog-Digital-Wandlung mit Unterdrückung von Eigenstörungen
EP2457106B1 (fr) Dispositif de mesure sélectif en fréquence et procédé de mesure sélectif en fréquence

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 20030207

AK Designated contracting states

Designated state(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE TR

RAP1 Party data changed (applicant data changed or rights of an application transferred)

Owner name: CREDENCE-SZ SYSTEMS GMBH

17Q First examination report despatched

Effective date: 20070525

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 20071005