CN108614230B - A kind of source power of lattice gauge and the simplification calibration method of receiver - Google Patents

Abstract

The invention discloses a simplified calibration method for source power and receiver of a network instrument, and belongs to the technical field of electronic testing. The present invention uses port i as a power meter to measure port j when port j is used as a source in a straight-through connection; uses the error model of source power and receiver calibration to deduce that when a straight-through connection is used, port j is used as a source, and port i is used as a source. The error calculation formula of the power meter; complete source power and receiver simplifies the calibration process; simplifies the number of connections of the power meter during calibration; does not increase the number of connections during S parameter calibration; can be extended to N-port calibration.

Description

A Simplified Calibration Method of Source Power and Receiver of Network Instrument

technical field

The invention belongs to the technical field of electronic testing, and in particular relates to a simplified calibration method for the source power of a network instrument and a receiver.

Background technique

The vector network analyzer performs S-parameter testing, and its internal components include a radio frequency signal source (RF Source in Figure 1), a reference receiver (a1, a2), and a measurement receiver (b1, b2). When performing power measurements, the signal source power needs to be calibrated.

Since more and more non-linear characteristics are considered during device testing, its own characteristics are also realized under specific power. Therefore, when using a network instrument to test such devices, it is necessary to calibrate the source power and receiver to achieve precise control of the source power output and precise measurement of the receiver.

The existing schemes are as follows:

The port i of the vector network analyzer is connected to a power meter for source power calibration;

The port j of the vector network analyzer is connected to a power meter for power calibration;

Calibrate the receiver parameters corresponding to port i;

Calibrate the receiver parameters corresponding to port j.

The existing scheme regards the source power and receiver calibration of each port as independent parts, and does not take advantage of the characteristic that the network instrument itself can be used as both a source and a receiver. As a result, there are many steps in the calibration process and the operation complexity is high.

When using a network instrument to test power sensitive devices, source power and receiver calibration are required. When multiple ports are required for source power and receiver calibration, the existing method is to perform source power and receiver calibration for each port separately. In addition, full two-port calibration is required, resulting in many calibration steps, complicated operation, and prone to human error.

Contents of the invention

Aiming at the above-mentioned technical problems existing in the prior art, the present invention proposes a simplified calibration method for the source power of the network instrument and the receiver, which is reasonable in design, overcomes the deficiencies of the prior art, and has good effects.

In order to achieve the above object, the present invention adopts the following technical solutions:

A simplified calibration method for the source power of a network instrument and a receiver, comprising the following steps:

Step 1: Reset the VNA;

Step 2: Connect port i to the power meter, record the reading of the reference receiver of port i, the power P _meas measured by the power meter, and the uncorrected value Γ _m of the reflection coefficient of the power meter measured by the vector network analyzer;

Step 3: Connect port i to port j, perform dual-port calibration on port i and port j, and record all S-parameter measurements;

Step 4: Record the reading a _jm of the reference receiver at port j and the reading b _im of the measuring receiver at port i when calibrating the through connection at two ports;

Step 5: Carry out the extraction of 10 errors of two ports;

Step 6: Obtain the reflection coefficient Γ _ps of the power meter according to the single-port error correction formula;

Among them, Γ _ps is the reflection coefficient of the power meter; Γ _m is the uncorrected value of the power meter reflection coefficient measured by the vector network analyzer; E _d is the directional error of port i; E _r is the reflection tracking error of port i; _s is the source matching error of port i;

According to formula (3), calculate the receiver tracking error E _rr of port i;

Among them, E _rr is the tracking error of the receiver; E _pr is the error from the source power test set of port i to the reference receiver; E _ps is the error from the source power test set of port i to the input terminal of the DUT; E _d is the error of port i E _r is the reflection tracking error of port i; E _s is the source matching error of port i; a _im is the measurement signal of the reference receiver of port i; Γ _ps is the reflection coefficient of the power meter; P _meas is Power meter measures power;

Step 7: Use the 10-term error of the two-port to correct the S parameters in the through measurement, and obtain S _ii , S _ij , S _ji ;

Step 8: When port j is used as the source output signal, connect port i and port j, and use formula (4) to obtain the measured power of port i And in combination with formula (3), calculate the receiver tracking error of port j;

in, is the measurement power of port i; b _{i_reccor} is the response correction value of the measurement receiver of port i; S _ii , S _jj , S _ij , and S _ji are the S parameters of the through-piece in the straight-through connection; E _l is the port j to port i load matching error;

Step 9: Connect the DUT and measure the S parameters of the DUT;

Step 10: Correct the source power by using the 10 errors of the S parameters and the receiver tracking error of the port;

Step 11: Correct the measurement value of the receiver based on the S parameters of the DUT, the 10 errors and the tracking error of the receiver;

Step 12: Complete the revision.

Preferably, in step 5, the 10 dual-port errors are respectively: E _di is the directional error of port i; E _dj is the directional error of port j; E _ri is the reflection tracking error of port i; E _rj is the port j’s reflection tracking error; E _si is the source matching error of port i; E _sj is the source matching error of port j; E _lij is the load matching error from port j to port i; E _lji is the load matching error from port i to port j Error; E _tij is the transmission tracking error from port j to port i; E _tji is the transmission tracking error from port i to port j.

Beneficial technical effects brought by the present invention:

The present invention uses port i as a power meter to measure port j when port j is used as a source in a straight-through connection; uses the error model of source power and receiver calibration to deduce that when a straight-through connection is used, port j is used as a source, and port i is used as a source. The error calculation formula of the power meter; complete source power and receiver simplifies the calibration process; simplifies the number of connections of the power meter during calibration; does not increase the number of connections during S parameter calibration; can be extended to N-port calibration.

Description of drawings

Figure 1 is a block diagram of the network analyzer.

Figure 2 is a flow chart of the source power calibration signal.

Figure 3 is a complete receiver power measurement signal flow diagram.

Figure 4 is a simplified flowchart of source power and receiver calibration.

Detailed ways

Below in conjunction with accompanying drawing and specific embodiment the present invention is described in further detail:

The invention proposes a simplified calibration method for network instrument source power and receiver, which can reduce calibration steps, improve test efficiency, reduce operation complexity, and reduce human error in operation.

1. Network instrument source power calibration

Because it is a signal flow diagram that introduces a single-port error, as shown in Figure 2, the error relationship is as follows:

Among them, E _d is the directional error of port i; E _r is the reflection tracking error of port i; E _s is the source matching error of port i; E _pr is the error from the source power test set of port i to the reference receiver; E _ps is the error from the port i source power test set to the input terminal of the device under test.

2. Network instrument receiver calibration

The flow chart of the error model of the network instrument is refined, the reference receiver error and the forward power transfer error are decomposed, and the 10-item error model is introduced. The completed signal flow is shown in Figure 3.

Because it is a signal flow diagram that introduces 10 errors, the error relationship is as follows:

Among them, E _d is the directional error of port i; E _r is the reflection tracking error of port i; E _s is the source matching error of port i; E _l is the load matching error of port i to _j ; j is the transmission tracking error; E _pr is the error from the source power test set of port i to the reference receiver; E _ps is the error from the source power test set of port i to the input terminal of the DUT.

3. Error acquisition process

(1) Error extraction of power meter connected to port i

Using the signal flow shown in Figure 2 can be obtained:

Among them, E _rr is the tracking error of the receiver; E _pr is the error from the source power test set of port i to the reference receiver; E _ps is the error from the source power test set of port i to the input terminal of the DUT; E _d is the error of the port i Directionality error; E _r is the reflection tracking error of port i; E _s is the source matching error of port i; a _im is the measurement signal of the reference receiver of port i; Γ _ps is the power meter

The reflection coefficient; P _meas is the power meter measuring power.

(2) Error extraction when port j is connected to port i

Connect port i and port j when port j is the source output signal. According to Figure 3, the following formula can be obtained

in, is the measured power of port i; b _{i_reccor} is the response correction value of the measuring receiver of port i; S _ii , S _jj , S _ij , and S _ji are the S parameters of the through-piece in the straight-through connection; E _l is the load from port j to i match error.

Using formula (4) to replace the power meter in formula (3) with the correction signal of the port i measurement receiver, the receiver tracking error of port j can be obtained.

So far, the power meter is connected through the port i, and the through connection between the ports i and j can complete the receiver tracking error acquisition of the ports i and j. Furthermore, the source power and receiver correction of ports i and j can be performed according to FIG. 3 .

4. The simplified source power and receiver calibration process is shown in Figure 4.

A simplified calibration method for the source power of a network instrument and a receiver, comprising the following steps:

Step 1: Reset the VNA;

Step 2: Connect port i to the power meter, record the reading of the reference receiver of port i, the power P _meas measured by the power meter, and the uncorrected value Γ _m of the reflection coefficient of the power meter measured by the vector network analyzer;

Step 3: Connect port i to port j, perform dual-port calibration on port i and port j, and record all S-parameter measurements;

Step 4: Record the reading a _jm of the reference receiver at port j and the reading b _im of the measuring receiver at port i when calibrating the through connection at two ports;

Step 5: Carry out the extraction of 10 errors of two ports;

Step 6: Obtain the reflection coefficient Γ _ps of the power meter according to the single-port error correction formula;

Among them, Γ _ps is the reflection coefficient of the power meter; Γ _m is the uncorrected value of the power meter reflection coefficient measured by the vector network analyzer; E _d is the directional error of port i; E _r is the reflection tracking error of port i; _s is the source matching error of port i;

According to formula (3), calculate the receiver tracking error E _rr of port i;

Among them, E _rr is the tracking error of the receiver; E _pr is the error from the source power test set of port i to the reference receiver; E _ps is the error from the source power test set of port i to the input terminal of the DUT; E _d is the error of port i E _r is the reflection tracking error of port i; E _s is the source matching error of port i; a _im is the measurement signal of the reference receiver of port i; Γ _ps is the reflection coefficient of the power meter; P _meas is Power meter measures power;

Step 7: Use the 10-term error of the two-port to correct the S parameters in the through measurement, and obtain S _ii , S _ij , S _ji ;

Step 8: When port j is used as the source output signal, connect port i and port j, and use formula (4) to obtain the measured power of port i And in combination with formula (3), calculate the receiver tracking error of port j;

in, is the measurement power of port i; b _{i_reccor} is the response correction value of the measurement receiver of port i; S _ii , S _jj , S _ij , and S _ji are the S parameters of the through-piece in the straight-through connection; E _l is the port j to port i load matching error;

Step 9: Connect the DUT and measure the S parameters of the DUT;

Step 10: Correct the source power by using the 10 errors of the S parameters and the receiver tracking error of the port;

Step 11: Correct the measurement value of the receiver based on the S parameters of the DUT, the 10 errors and the tracking error of the receiver;

Step 12: Complete the revision.

In step 5, the 10 dual-port errors are: E _di is the directional error of port i; E _dj is the directional error of port j; E _ri is the reflection tracking error of port i; E _rj is the reflection error of port j Tracking error; E _si is the source matching error of port i; E _sj is the source matching error of port j; E _lij is the load matching error from port j to port i; E _lji is the load matching error from port i to port j; E _tij is the transmission tracking error from port j to port i; E _tji is the transmission tracking error from port i to port j.

Of course, the above descriptions are not intended to limit the present invention, and the present invention is not limited to the above examples. Changes, modifications, additions or substitutions made by those skilled in the art within the scope of the present invention shall also belong to the present invention. protection scope of the invention.

Claims (2)

1. the simplified calibration method of the source power of a kind of network instrument and receiver, it is characterized in that: comprise the steps: Step 1: Reset the VNA; Step 2: Connect port i to the power meter, record the reading of the reference receiver of port i, the power P _meas measured by the power meter, and the uncorrected value Γ _m of the reflection coefficient of the power meter measured by the vector network analyzer; Step 3: Connect port i to port j, perform dual-port calibration on port i and port j, and record all S-parameter measurements; Step 4: Record the reading a _jm of the reference receiver at port j and the reading b _im of the measuring receiver at port i when calibrating the through connection at two ports; Step 5: Carry out the extraction of 10 errors of two ports; Step 6: Obtain the reflection coefficient Γ _ps of the power meter according to the single-port error correction formula; Among them, Γ _ps is the reflection coefficient of the power meter; Γ _m is the uncorrected value of the power meter reflection coefficient measured by the vector network analyzer; E _d is the directional error of port i; E _r is the reflection tracking error of port i; _s is the source matching error of port i; According to formula (3), calculate the receiver tracking error E _rr of port i; Among them, E _rr is the tracking error of the receiver; E _pr is the error from the source power test set of port i to the reference receiver; E _ps is the error from the source power test set of port i to the input terminal of the DUT; E _d is the error of port i E _r is the reflection tracking error of port i; E _s is the source matching error of port i; a _im is the measurement signal of the reference receiver of port i; Γ _ps is the reflection coefficient of the power meter; P _meas is Power meter measures power; Step 7: Use the 10-term error of the two-port to correct the S parameters in the through measurement, and obtain S _ii , S _ij , S _ji ; Step 8: When port j is used as the source output signal, connect port i and port j, and use formula (4) to obtain the measured power of port i And in combination with formula (3), calculate the receiver tracking error of port j; in, is the power measured at port i; b _{i_reccor} is the response correction value of the measurement receiver of port i; S _ii , S _jj , S _ij , and S _ji are the S parameters of the through-piece in the case of through-connection; E _l is from port j to port The load matching error of i; Step 9: Connect the DUT and measure the S parameters of the DUT; Step 10: Correct the source power by using the 10 errors of the S parameters and the receiver tracking error of the port; Step 11: Correct the measurement value of the receiver based on the S parameters of the DUT, the 10 errors and the tracking error of the receiver; Step 12: Complete the revision. 2. the source power of network instrument according to claim 1 and the simplified calibration method of receiver, it is characterized in that: in step 5, 10 two-port errors are respectively: E _di is the directional error of port i; _dj is the directional error of port j; E _ri is the reflection tracking error of port i; E _rj is the reflection tracking error of port j; E _si is the source matching error of port i; E _sj is the source matching error of port j; _lij is the load matching error from port j to port i; E _lji is the load matching error from port i to port j; E _tij is the transmission tracking error from port j to port i; E _tji is the transmission tracking error from port i to port j .