DE102008027033B4 - Measuring method and measuring device for determining parameters at the operating point - Google Patents

Abstract

Measuring method for measuring scattering parameters of a test object (42),
wave quantities (a _{1, F} , a _{2, F} , a _{1, FR} , a _{2, FR} ) of traveling waves and wave quantities (b _{1, F} , b _{2, F} , b _{1, FR} , b _{2, FR} ) of returning waves measured at a first measuring port (40, T1) and at a second measuring port (41, T2),
where the following steps are performed:
- feeding a first measurement signal into the first measurement port (40, T1), measuring the wave quantities of the outgoing (a _{1, F} , a _{2, F} ) waves, and measuring the wave quantities (b _{1, F} , b _{2, F} ) of the returning ones Waves;
- feeding a second measurement signal into the second measurement port (41, T2) while the first measurement signal is fed to the first measurement port (40, T1), measuring the wave quantities (a _{1, FR} , a _{2, FR} ) of the traveling waves, and Measuring the wave quantities (b _{1, FR} , b _{2, FR} ) of the returning waves;
- determining corrected wave quantities by means of a correction calculation;
- determining scattering parameters of the measurement object (42) from the corrected wave quantities;
characterized,
that before the correction calculation the differences of the measured ...

Description

The The invention relates to a measuring method and a measuring device for Determination of the parameters of DUTs, in particular the S-parameters at the working point.

Conventionally to the full Measurement of DUTs performed a separate forward and backward measurement. While everyone These two measurements are entered into a measuring port of the test object Signal fed while the remaining Test gates remain without signal. A measurement in the working point However, this is not guaranteed. About that in addition, this usually requires a prior calibration with calibration standards and requires one at least twice as long as a unidirectional one Measurement.

The German patent application DE 102 46 700 A1 shows a measuring device for measuring objects to be measured, which solves the problem of measurement at the operating point by simultaneous application of two signals of different frequency at different test ports to the test object. However, it requires two independent signal generators. In addition, a survey without working point falsification or damage to the test object is not guaranteed by the second measurement signal.

The German patent application DE 199 26 454 A1 shows a vectorial network analyzer with at least two test ports whose measuring branches each have four gates with associated measuring points. Each measuring port is assigned its own high-frequency generator, wherein the individual high-frequency signals are distinguishable from each other and are simultaneously supplied to the associated measuring points.

Of the The invention is based on the object, a method and a device to create a measurement of the parameters of DUTs at the working point and only require a small effort.

The Task is according to the invention for the process by the characteristics of the independent Claim 1 and for the device is achieved by the features of independent claim 8. advantageous Further developments are the subject of the dependent claims.

• – Einspeisung eines ersten Messsignals in das erste Messtor durch die Sende-Einrichtung, und Messung der Wellengrößen der hinlaufenden und rücklaufenden Wellen durch die Empfangs-Einrichtung.
• – Einspeisung eines zweiten Messsignals in das zweite Messtor durch die Sende-Einrichtung, während das erste Messsignal in das erste Messtor eingespeist wird und Messung der Wellengrößen der hinlaufenden und rücklaufenden Wellen durch die Empfangs-Einrichtung.
• – Bestimmung von korrigierten Wellengrößen anhand einer Korrekturrechnung durch die Verarbeitungs-Einrichtung, z. B. als 12-Term oder 10-Term Korrekturrechnung.
• – Bestimmung von Streuparametern des Messobjekts aus den korrigierten Wellengrößen durch die Verarbeitungs-Einrichtung.
• – Bildung der Differenzen der gemessenen Wellengrößen durch die Verarbeitungs-Einrichtung vor Durchführung der Korrekturrechnung und Durchführung der Korrekturrechnung auf Basis dieser Differenzen. So ist eine Vermessung des Messobjekts im Arbeitspunkt auch bei Rückwärtsmessung möglich.

A measuring device for measuring scattering parameters of a measuring object has at least one processing device, a transmitting device and a receiving device. The measuring device measures the wave sizes of the traveling waves and the wave sizes of the returning waves on a first measuring port and on a second measuring port. It performs the following steps:

• - Feeding of a first measurement signal in the first measuring port by the transmitting device, and measuring the wave sizes of the running and returning waves by the receiving device.
• Feeding the second measuring signal into the second measuring port by the transmitting device while the first measuring signal is fed into the first measuring port and measuring the wave quantities of the traveling and returning waves by the receiving device.
• Determination of corrected wave quantities based on a correction calculation by the processing device, e.g. As a 12-term or 10-term correction calculation.
• - Determination of scattering parameters of the measurement object from the corrected wave sizes by the processing device.
• - Formation of the differences of the measured wave quantities by the processing device before performing the correction calculation and performing the correction calculation on the basis of these differences. Thus, a measurement of the DUT at the operating point is also possible with backward measurement.

The Amplitude of the second measurement signal is advantageously lower as the amplitude, more advantageously less than one fifth the amplitude, particularly advantageously one tenth of the amplitude of the first measurement signal. Damage to the test object or a falsification the measurement by high levels of the measurement signal in reverse measurement avoided.

Of the Period of common feed of the first measurement signal and the second measuring signal is preferably shorter than the period of the sole Infeed of the first measurement signal, particularly preferably shorter than a fifth the sole supply of the first measurement signal. This leads to a short measuring time with high measuring accuracy.

The measuring device preferably operates the measurement object by feeding in the first measurement signal at its operating point. It preferably feeds the second measurement signal in such a way that the measurement object continues to operate largely at its operating point. Thus, the operating point of the measuring object is not distorted even during the backward measurement.

advantageously, the transmitting device generates the first measuring signal and the second Measuring signal with largely identical frequency and largely identical Phase. The processing device preferably compensates for deviations Frequencies and phases by means of a correction calculation. That's one phase-synchronous measurement and thus a high measurement accuracy possible.

Prefers the measuring device is a network analyzer. He is preferred before implementation the measurements by means of a 12-term method or a 10-term method calibrated using calibration standards. That's a lot accurate measurement possible.

at another embodiment the network analyzer will not go down before performing the measurements Calibrated use of calibration standards. He is then using correction coefficients determined in the manufacturing process and Calibrated during the measurement of determined wave sizes. That's one accurate measurement without calibration effort for the user possible.

The Transmitter contains prefers only one signal generator. It generates the two measuring signals. The transmitting device preferably contains at least one Attenuator. It adjusts the amplitude of at least one of the two measurement signals. So a construction with only a few components is possible. On a complex second signal generator can be dispensed with.

Of the Network analyzer features preferably over at least 4 recipients. So is a fast and reliable Measurement possible.

following the invention with reference to the drawing, in which an advantageous Embodiment of Invention is described by way of example. In the drawing demonstrate:

1 a first embodiment of a measuring device according to the invention;

2 an exemplary measurement setup;

3 a detail of a second embodiment of a measuring device according to the invention;

4 a detail of a third embodiment of a measuring device according to the invention;

5 a measurement structure according to the invention, and

6 an embodiment of the sequence of a measuring method according to the invention.

First, based on the 1 the structure and operation of a first measuring device according to the invention explained. Based on 2 the construction and operation of an exemplary measurement setup is shown. through 3 - 4 the construction and operation of further inventive measuring devices is shown. Based on 5 and 6 Finally, the structure and operation of a measurement setup according to the invention and the sequence of a method according to the invention are shown. Identical elements have not been repeatedly shown and described in similar figures.

1 shows a first embodiment of a measuring device according to the invention. In the exemplary embodiment shown, the measuring device is a vector network analyzer.

shown is also the embodiment a 2-port network analyzer.

At each gate T1, T2 of the measuring device 1 is a separate excitation / reception unit 2 ₁ respectively. 2 ₂ available. In this case, the excitation / receiving units have 2 ₁ respectively. 2 ₂ only via a common signal generator 30 with which the measurement object 42 can be acted upon by an excitation signal. It is clearly evident that the provision of only one signal generator 30 requires significantly less effort than the provision of two separate signal generators.

In the illustrated application, the measurement object 42 a 2-goal, for example a bandpass Amplifier, a damping circuit or the like. Each of the two gates of the measurement object 42 is with one of the two ports T1 and T2 of the measuring device 1 connected.

The signal generator 30 is via a signal splitting device 23 with a signal distributor (signal splitter) 5 ₁ respectively. 5 ₂ connected. The signal splitting device 23 divides the signal in an adjustable ratio. This setting is made by means of a control line 21 by a processing device 51 , An exemplary signal sharing device 23 is determined by the 4 explained in more detail. A signal branch 6 ₁ respectively. 6 ₂ is in each case via a bridge (directional coupler) 7 ₁ respectively. 7 ₂ with the associated gate T1 or T2 in conjunction. The other branch 8 ₁ respectively. 8 ₂ is with a mixer 10 ₁ respectively. 10 ₂ a first receiving device 9 ₁ respectively. 9 ₂ the respective excitation / receiving unit 2 ₁ respectively. 2 ₂ connected. The first receiving device 9 ₁ respectively. 9 ₂ thus receives the excitation signal. Further, the mixer 10 ₁ respectively. 10 ₂ an oscillator signal is supplied by an internal oscillator 31 is generated and the mixer 10 ₁ respectively. 10 ₂ via two signal distributors (signal splitter) 24 and 11 ₁ respectively. 11 ₂ and one amplifier each 12 ₁ respectively. 12 ₂ is supplied.

The same oscillator 31 supplies the signal distributor via the other signal branch 11 ₁ respectively. 11 ₂ and a corresponding amplifier 13 ₁ respectively. 13 ₂ a mixer 14 ₁ respectively. 14 ₂ the respective excitation / receiving unit 2 ₁ respectively. 2 ₂ , The mixer 14 ₁ respectively. 14 ₂ stands over an isolation amplifier 16 ₁ respectively. 16 ₂ and the bridge 7 ₁ respectively. 7 ₂ with the associated gate T1 or T2 in conjunction. Thus, the signal received by the associated port T1 is transmitted by the measurement object via this signal branch 42 reflected to the gate T1 or through the measurement object 42 received from the gate T1 to the gate T2 transmitted signal. Accordingly, this signal branch of the excitation / receiving unit 2 ₂ that of the measurement object 42 reflected to the gate T2 or through the measurement object 42 received from the gate T1 to the door T2 received signal. The mixers 10 ₁ and 14 ₁ the first excitation / reception unit 2 ₁ set the received signal to a first intermediate frequency position with the intermediate frequency f _IF1 while the mixers 10 ₂ and 14 ₂ the second excitation / reception unit 2 ₂ convert the received signal into a second intermediate frequency position with the intermediate frequency f _IF2 . In this case, the intermediate frequencies f _IF1 and f _{IF2 are} not necessarily identical.

That from the mixers 10 ₁ respectively. 10 ₂ generated intermediate frequency reference signal IF1 or IF2 and that of the mixers 14 ₁ respectively. 14 ₂ generated intermediate frequency measuring signal M1 or M2 is an analog / digital converter in the processing device 51 supplied with a signal evaluation and control unit in the processing facility 51 communicates. In this an evaluation of the reference signals and the measurement signals. The processing facility 51 also controls via control lines 19 . 20 the signal generator 30 and the oscillator 31 such that they produce a signal with a predetermined frequency f _SO1 , f _LO1 and with a predetermined phase φ _SO1 , φ _LO1 .

About the further control line 21 stands the processing facility 51 with the signal splitting device 23 in conjunction, giving the signal amplitude of the signal generator 30 generated excitation signal at the two excitation / receiving units 2 ₁ and 2 ₂ is controllable. Since the actual amplitude of the excitation signal is detected via the intermediate frequency reference signals IF1 and IF2, a control loop for the exact regulation of the excitation amplitude can be formed in this way.

Further control lines for setting the amplification factors of the amplifiers in the excitation / receiving units 2 ₁ and 2 ₂ are also conceivable.

The control lines 19 to 21 can become a bus system 25 , in particular a LAN bus system, are summarized.

Normally, in network analyzers with only one transmitting oscillator and one local oscillator, one after the other, forward measurements and backward measurements are carried out when the connections are interchanged. According to the invention, however, a simultaneous forward measurement and backward measurement is instead performed after a single forward measurement. At the single forward measurement, the signal splitting device becomes 23 from the processing facility 51 controlled such that only one signal from the transmitting oscillator 30 in the first excitation / reception unit 2 ₁ arrives. In the subsequent concurrent forward measurement and backward measurement, the signal splitter becomes 23 from the processing facility 51 controlled such that a signal from the transmitting oscillator 30 in the first excitation / reception unit 21 and a significantly attenuated signal, z. B. with a tenth of the amplitude of the first signal in the second excitation / reception unit 2 ₂ arrives. Thus, signals of different amplitude but identical frequency and phase in the two test ports T1, T2 of the measurement object 42 fed. The exact sequence of the measurements and the further processing of the measurement results is based on the following figures, in particular 6 clarified.

2 shows an exemplary measurement setup. A measurement object 42 is over a first test gate 40 and a second test gate 41 connected to a meter. By means of directional couplers 47 and 48 Wavelengths of traveling and returning waves are measured. The measurement object 42 is in a forward measurement at the first test port 40 subjected to a measurement signal. About the connection 44 become the measurement object 42 returning waves measured. About the connection 43 the waves going to the target are measured. About the connection 46 the returning waves are measured. In a subsequent backward measurement, the measurement object becomes 42 over the second gate 41 subjected to a measurement signal. During this second measurement, the directional couplers 47 and 48 interchanged to all of the DUT 42 to measure transmitted and reflected waves. Since the meter before performing the measurements z. B. calibrated by means of a 10-term calibration method or a 12-term calibration method, the obtained wave sizes can now be corrected. From the corrected wave sizes, the scattering parameters of the DUT can be determined 42 be determined. However, in order to achieve a backward measurement at the operating point, that is to say simultaneous feedthrough in the forward direction, a measuring device with two transmission oscillators is usually necessary.

In 3 a second embodiment of a measuring device according to the invention is shown. The measuring device shown here is a vector network analyzer. It includes a processing facility 51 , a transmitting device 50 , a reception facility 52 and a display device 55 , The processing device 51 is with the sending facility 50 , the reception facility 52 and with the display facility 55 connected. The transmitting device 50 is by means of a plurality of terminals 53 with the measurement object 42 connected. The receiving device is by means of a plurality of terminals 54 with the measurement object 42 connected. The processing facility 51 corresponds to the processing facility 51 out 1 , The transmitting device 50 and the receiving device 52 fulfill thereby largely the same tasks as the excitation / receiving units 2 ₁ and 2 ₂ out 1 , However, oscillators required for transmitting and receiving are in the transmitting device 50 or the receiving device 52 integrated.

The processing facility 51 controls the transmitting device 50 , the reception facility 52 , the display device 55 and the course of the measurement. It sends instructions to the transmitting device 50 which signals this at which time over which of the plurality of terminals 53 to the measurement object 42 to send. It also sends instructions to the receiving device 52 in which settings this at which time signals from which of the plurality of terminals 54 to receive.

The transmitting device 50 contains exactly one signal generator, which generates all measuring signals. If several measurement signals are needed at the same time, they are generated by means of attenuators and phase shifters from the signal emitted by a signal generator. This ensures the phase synchronism and frequency synchronicity of the various measurement signals. Alternatively, multiple signal generators are used to generate the multiple measurement signals. In this case, however, additional measures to achieve a phase synchronism and frequency synchronicity of the various measurement signals are necessary. Any remaining deviations from the desired frequency, phase and amplitude of the measurement signals are by means of one of the processing device 51 compensated correction invoice.

The reception facility 52 contains at least 4 recipients. This is necessary in order to measure at at least two test ports simultaneously running and returning wave sizes. If there are fewer than twice the number of test ports on receivers, several consecutive measurements must be taken to measure all wave sizes. However, the measured values thus obtained are not synchronous and therefore of lower accuracy.

The exact sequence of a measurement will be explained later on the basis of 6 explained in more detail.

In 4 a detail of a third embodiment of the measuring device according to the invention is shown. The elements shown in this figure are for example in a signal-division device 23 like her 1 can be seen, arranged. About a connection 60 the signal generated by a transmission oscillator is input. A signal distributor 61 (signal splitter) splits the signal into two parts and sends them to the decoupling amplifiers 62 and 63 further. These direct the decoupled signals to the switches 64 and 65 further. From the counters 64 and 65 the signals are switched and to the attenuators 66 and 67 forwarded. The attenuators 66 and 67 attenuate the signals to an adjustable level. The resulting signals are sent via the connectors as needed 68 . 69 directed to the gates of a DUT. They have almost identical frequency and almost identical phase. Possible deviations are compensated in a correction calculation. However, the amplitudes of the signals may differ. The switches 64 and 65 and the attenuators 66 and 67 are doing by a processing device, eg. B. from the processing device 51 out 1 controlled. Alternatively, a structure consisting only of an adjustable signal distributor (signal splitter) is conceivable. By the circuit elements shown here, a targeted division of the oscillator signal on two measuring paths is possible.

5 shows a measurement structure according to the invention. The structure largely corresponds to the exemplary measurement setup 1 , About the connections 44 and 46 become the measurement object 42 returning waves measured. About the connections 43 and 45 be on the test object 42 measured incoming waves. A true backward measurement does not take place here. The directional coupler 47 and 48 are not interchanged, since in each case a receiver for the incoming and outgoing wave is connected. In addition, during the forward measurement, a weaker second measurement signal of the same frequency and phase temporarily becomes the second measurement port 41 fed. The resulting wave sizes will be at all four, at the terminals 43 . 44 . 45 and 46 measured connected receivers.

The wave quantities of the sole forward measurement and the combined measurement are sent to the processing device 51 out 1 respectively. 3 forwarded. This calculates corrected wave quantities and from this the scattering parameters of the measurement object.

The exact sequence of the measurement and correction calculation is described below on the basis of 6 shown.

6 shows an embodiment of the sequence of a measuring method according to the invention. The measurement object 42 comes with the gauges 40 . 41 the measuring device, here a vector network analyzer, connected. The measurement object 42 has at least two goals. The measuring device also has at least two measuring ports 40 . 41 , In a first step 80 a forward measurement is performed. This is at a first test gate 40 of the measurement object 42 a measuring signal is fed. Meanwhile, at both gauges 40 . 41 the wave sizes of the outgoing waves a _{1, F} , a _{2, F} and returning waves b _{1, F} , b _{2, F} measured. These wave sizes are recorded.

In a second step 81 is in addition to the first measurement signal, which continues to the first test port 40 is fed, a second measurement signal at the second test port 41 fed. The second measurement signal has a largely identical frequency and phase with respect to the first measurement signal. Any deviations in frequency and phase will be compensated in a later step. The amplitude of the second measurement signal is less than the amplitude of the first measurement signal. It is preferably less than 1/5, particularly preferably 1/10 of the amplitude of the first measurement signal. Also during this step will be on both gauges 40 . 41 the wave sizes of the traveling waves a _{1, FR} , a _{2, FR} and returning waves b _{1, FR} , b _{2, FR} measured.

In a third step 82 the differences of the measured wave sizes are determined. The differences correspond approximately to the expected wave sizes of a backward measurement in the operating point. a 1, corr = a 1, FR - a 1, F a 2, corr = a 2, FR - a 2, F b 1, corr = b 1, FR - b 1, F b 2, corr = b 2, FR - b 2, F

The quantities a _{1, F} , a _{2, F are} the wave sizes of the trailing, b _{1, F} , b _{2, F} the wave sizes of the returning waves in pure forward measurement and the quantities a _{1, FR} , a _{2, FR} the wave sizes of going and the sizes b _{1, FR} , b _{2, FR} the wave sizes of the returning waves in combined forward measurement and backward measurement. The quantities a _{1, corr} , a _{2, corr} , b _{1, corr} , b _{2, corr} are the differences of the measured wave quantities.

In a fourth step 83 is a correction calculation, z. B. by the 10-term method or by the 12-term method with the measured wave quantities of the forward measurement a _{1, F} , a _{2, F} b _{1, F} , b _{2, F} and the calculated wave sizes a _{1, corr} , a _{2, corr} , b _{1, corr} , b _{2, corr} . The calculated wave sizes correspond doing the wave sizes of a hypothetical backward measurement at the operating point. Thus, corrected wave sizes a _{22, corr} , b _{22, corr} , a _{21, corr} , b _{21, corr} , a _{11, corr} , b _{11, corr} , a _{12, corr} , b _{12, corr are} determined. For this purpose, certain calibration variables e ₀₀ , e ₀₁ , e ₁₀ , e ₁₁ , e _'22 , e' ₂₃ , e _'32 , e' ₃₃ are used in the course of calibration measurements previously performed on the measuring setup used.

From these corrected wave sizes a _{22, corr} , b _{22, corr} , a _{21, corr} , b _{21, corr} , a _{11, corr} , b _{11, corr} , a _{12, corr} , b _{12, corr} are in a fifth step 84 the scattering parameters S _{11, corr} , S _{12, corr} , S _{21, corr} , S _{22, corr of} the measurement object are calculated as follows:

in the Following are two possible uses of the illustrated Shown method.

1. Hot S parameter measurement

As already indicated, it is possible with the aid of this method to measure measured objects at the operating point. Due to the low transmission power of the signal used for the backward measurement of the operating point is not falsified on the one hand, on the other hand, a falsification of the results by an excessive signal Actuation of the measuring gate, which is not usually provided for the acceptance of signals, avoided. Also, damage to the test object due to excessive input power at the second test port is thus avoided. However, a prerequisite of this method is a preliminary determination of the error parameters of the measurement setup, ie of the measuring device and all connection means to the measurement object. These error parameters are stored in error matrices and used to correct the measurement results. This calibration requires the sequential connection of several calibration standards to the measuring device's measuring ports, causing considerable expense. This effort can be reduced by automatically connecting the calibration standards.

2. Automatic calibration

On a calibration by means of the connection of calibration standards by the user of the meter can be omitted if the procedure described below is applied. First becomes the meter while calibrated during the manufacturing process. Ie. the error matrices of the meter are determined. These do not yet contain any information in terms of by the connecting means, by means of which the measuring object connected, caused measurement errors. So include these Measurement errors reflections at the test ports and the transmissions through the measuring gates.

measurement error in the transmission can by connection of the two connecting means, which for connection be used to calibrate the device under test. To this Calibration can be omitted if a small measurement error is accepted. Especially when using short connecting cables this procedure does not cause any serious measuring errors.

The Measurement error due to reflection at the connections of the connecting means on the side of the tester also be determined by this one calibration. at Connection of a measuring object by means of the connecting means can at unidirectional measurement continues the reflections at the port of the bonding agent on the test object side and on the test object be determined on the sending side.

Consequently For unidirectional measurement, only the reflections are at the connection of the bonding agent on the test object side and on the test object not known on the receiving side. These remaining error coefficients be detailed as above described by means of a simultaneous feed of a weaker second Excitation signal in the second Messtor determined. Because for this pure reflection measurement only a low dynamics necessary is enough therefor a very short measuring time. So can a nearly completely calibrated Measurement after only the connection of the two test leads done. An incomplete calibrated, but despite its low-error measurement is waiver possible on this calibration measurement.

The invention is not limited to the illustrated embodiment. As already mentioned, different measuring devices can be used. It is also possible to use higher numbers of test ports. All features described above or features shown in the figures can be combined with each other in any advantageous manner within the scope of the invention. In particular, the basis of the 3 and 4 described details in combination with the embodiment of 1 and / or in combination with each other.

Claims (16)

Measuring method for measuring scattering parameters of a test object ( 42 wave quantities (a _{1, F} , a _{2, F} , a _{1, FR} , a _{2, FR} ) of traveling waves and wave quantities (b _{1, F} , b _{2, F} , b _{1, FR} , b _{2, FR} ) returning waves at a first measuring port ( 40 , T1) and at a second test port ( 41 , T2), wherein the following steps are carried out: feeding a first measuring signal into the first measuring port ( 40 , T1), measuring the wave quantities of the traveling (a _{1, F} , a _{2, F} ) waves, and measuring the wave quantities (b _{1, F} , b _{2, F} ) of the returning waves; Feeding a second measuring signal into the second measuring port ( 41 , T2), while the first measurement signal in the first test port ( 40 , T1), measuring the wave quantities (a _{1, FR} , a _{2, FR} ) of the traveling waves, and measuring the wave quantities (b _{1, FR} , b _{2, FR} ) of the returning waves; - determining corrected wave quantities by means of a correction calculation; Determining scattering parameters of the measurement object ( 42 ) from the corrected wave sizes; characterized in that before the correction calculation the differences of the measured wave quantities (a _{1, F} , a _{2, F} , a _{1, FR} , a _{2, FR} , b _{1, F} , b _{2, F} , b _{1, FR} , b _{2 , FR} ) and the correction calculation is performed on the basis of these differences. Measuring method according to claim 1, characterized that the amplitude of the second measurement signal is less than the amplitude, advantageously less than one fifth of the amplitude, especially advantageously one tenth of the amplitude of the first measurement signal is. Measuring method according to claim 1 or 2, characterized that the period of common feed of the first measurement signal and the second measurement signal shorter as the period of sole supply of the first measurement signal, advantageously shorter as a fifth is the sole supply of the first measurement signal. Measuring method according to one of claims 1 to 3, characterized in that the measurement object ( 42 ) is operated by the supply of the first measurement signal in its operating point, and that the feeding of the second measurement signal takes place in such a way that the measurement object ( 42 ) continues to operate at least approximately at its operating point. Measuring method according to one of claims 1 to 4, characterized, that the first measurement signal and the second measurement signal is at least substantially identical Have frequency and an at least substantially identical phase, and that may be minor deviating frequencies and phases by means of a correction calculation be compensated. Measuring method according to one of claims 1 to 5, characterized, that to carry out the Measurements a network analyzer is used, and that the network analyzer before performing the measurements using a 12-term or 10-term method using calibration standards is calibrated. Measuring method according to one of claims 1 to 5, characterized, that to carry out the Measurements a network analyzer is used, and that the network analyzer by means of the manufacturing process Correction coefficients and calibrated during the measurement calibrated wave sizes becomes. Measuring device ( 1 ) for measuring scattering parameters of a test object ( 42 ), wherein the measuring device ( 1 ) via at least one processing device ( 51 ), a transmitting device ( 50 ) and a receiving device ( 52 ), the measuring device ( 1 Wavelengths (a _{1, F} , a _{2, F} , a _{1, FR} , a _{2, FR} ) of traveling waves and wave quantities (b _{1, F} , b _{2, F} , b _{1, FR} , b _{2, FR} ) of returning waves at a first test gate ( 40 , T1) and at a second test port ( 41 , T2), the processing device ( 51 ) of the measuring device ( 1 ) for carrying out the following steps: - feeding a first measuring signal into the first measuring port ( 40 , T1) by the transmitting device ( 50 ), and measurement of the wave sizes (a _{1, F} , a _{2, F} ) of the traveling waves and measurement of the wave sizes (b _{1, F} , b _{2, F} ) of the returning waves by the receiving device ( 52 ); Feeding a second measuring signal into the second measuring port ( 41 , T2) by the transmitting device ( 50 ), while the first measurement signal enters the first measurement port ( 40 , T1) and measuring the wave sizes of the traveling (a _{1, FR} , a _{2, FR} ) waves and measuring the wave sizes (b _{1, FR} , b _{2, FR} ) of the returning waves by the receiving device ( 52 ); Determination of corrected wave quantities by means of a correction calculation by the processing device ( 51 ); - Determination of scattering parameters of the test object ( 42 ) from the corrected wave quantities by the processing device ( 51 ), characterized in that the processing device ( 51 ) before carrying out the correction calculation, the differences of the measured wave quantities (a _{1, F} , a _{2, F} , a _{1, FR} , a _{2, FR} , b _{1, F} , b _{2, F} , b _{1, FR} , b _{2, FR} ) and makes the correction calculation based on these differences. Measuring device ( 1 ) according to claim 8, characterized in that the amplitude of the second measuring signal less than the amplitude, advantageously less than one fifth of the amplitude, particularly advantageous legally one tenth of the amplitude of the first measurement signal. Measuring device ( 1 ) according to claim 8 or 9, characterized in that the period of common feed of the first measurement signal and the second measurement signal is shorter than the period of sole supply of the first measurement signal, advantageously shorter than one fifth of the sole supply of the first measurement signal. Measuring device ( 1 ) according to one of claims 8 to 10, characterized in that the measuring device ( 1 ) the measuring object ( 42 ) is operated by supplying the first measurement signal at its operating point, and that the measuring device ( 1 ) feeds the second measurement signal in such a way that the measurement object ( 42 ) continues to operate at least approximately at its operating point. Measuring device ( 1 ) according to one of claims 8 to 11, characterized in that the transmitting device ( 50 ) generates the first measurement signal and the second measurement signal with at least substantially identical frequency and at least substantially identical phase, and that the processing device ( 51 ) possibly slightly different frequencies and phases are compensated by means of a correction calculation. Measuring device ( 1 ) according to one of claims 8 to 12, characterized in that the measuring device ( 1 ) is a network analyzer, and that the network analyzer is calibrated using a 12-term or 10-term method using calibration standards prior to making the measurements. Measuring device ( 1 ) according to one of claims 8 to 12, characterized in that the measuring device ( 1 ) is a network analyzer, and that the network analyzer is calibrated by means of correction coefficients determined in the manufacturing process and wave quantities determined in the course of the measurement. Measuring device ( 1 ) according to one of claims 8 to 14, characterized in that the transmitting device ( 50 ) a signal generator ( 30 ) contains that the signal generator ( 30 ) the first and the second measuring signal generates that the transmitting device ( 50 ) at least one attenuator ( 66 . 67 ) and that the attenuator ( 66 . 67 ) adjusts the amplitude of at least one of the two measurement signals. Measuring device ( 1 ) according to one of claims 8 to 15, characterized in that the network analyzer has at least 4 receivers.