Source correction factor calculation method and system based on N-port calibration and storage medium

Abstract

The invention belongs to the technical field of vector network analyzers, and particularly relates to a source correction factor calculation method and system based on N-port calibration and a storage medium, a vector network analyzer port is connected with a power meter, a source correction factor of a source calibration port is calculated, and then all receiver error terms are calculated; and finally, source correction factors of other ports are calculated through straight-through measurement of N port calibration and a receiver error item. The method has the advantages that on the basis of N port calibration, only one vector network analyzer port needs to be connected with the power meter, the source correction factor of the port is calculated, and the source correction factor of any other port can be directly calculated.

Description

Technical Field

[0001] The present application belongs to the technical field of vector network analyzers, and in particular relates to a source correction factor calculation method, system and storage medium based on N-port calibration. Background Art

[0002] The measurement results of modern vector network analyzers are generally expressed as ratios of power waves, such as S parameters. The traditional view is that both waves and S parameters are linear, which means that the measurement of these values ​​is independent of the absolute source power. However, some devices have certain nonlinearities, and their characteristics must be defined at a specific input power. Therefore, when measuring some devices, it is necessary to ensure the accuracy of the source power through source calibration, so as to obtain its accurate measurement value.

[0003] The basic method of source power calibration is to measure and correct the source power at each frequency point. The existing source calibration scheme is to connect the power meter to all the ports of the vector network analyzer that need to be calibrated one by one, and then obtain the power meter readings at each frequency point. According to the offset between the power meter readings and the target value, the source correction factor of each port is calculated. The existing technology mainly calibrates the source power of each port one by one. The disadvantage of the method of calibrating the source power of each port one by one is that each calibration port needs to be repeatedly measured in the calibration steps, and each calibration step requires a manual physical connection, which is time-consuming and labor-intensive. Summary of the invention

[0004] Based on the above problems, the source correction factor calculation method based on N-port calibration proposed in this application is better than the traditional method. Its main advantage is that the source correction factors of all ports can be calculated through a physical connection of any port, which greatly reduces the operation repeatability and improves the calibration efficiency. Its technical solution is:

[0005] A source correction factor calculation method based on N-port calibration, connecting a power meter to a port of a vector network analyzer, calculating the source correction factor of the source calibration port, then calculating all receiver error terms, and finally calculating the source correction factors of other ports through the through measurement of the N-port calibration and the receiver error terms.

[0006] Preferably, the formula for calculating the source correction factor of the source calibration port is as follows:

[0007] SC i =P i -P iMea ;

[0008] Where: i represents the source calibration port, SC i represents the source correction factor of the source calibration port, P i Indicates the port power of the source calibration port setting, P iMeaRepresents the power meter reading, which is the actual power at the source calibration port.

[0009] Preferably, based on the single-port calibration measurement data and the error term, a reference receiver tracking error term of the source calibration port is calculated:

[0010]

[0011] Where: RR ii represents the reference receiver tracking error term at the source calibration port, P iMea Indicates the power meter reading, a iM Indicates the measured value on the power meter measurement receiver connected to the source calibration port. ES ii represents the source mismatch error at the source calibration port, Γ Sen Indicates the port reflection coefficient when the source calibration port is connected to the power meter.

[0012] Preferably, the reference receiver error terms and the measurement receiver error terms of other calibration ports are calculated:

[0013]

[0014] BT jj =ET ji ·RR ii ;

[0015] Where: i represents the source calibration port, j represents other ports, RR ii represents the reference receiver tracking error term at the source calibration port, RR jj represents the reference receiver tracking error term on other ports, ED ii represents the directivity error of the source calibration port, ER ii is the reflection tracking error at the source calibration port, ES ii is the source mismatch error at the source calibration port, ET ij represents the transmission tracking error term from other ports to the source calibration port, EL ij represents the load matching error term from other ports to the source calibration port, BT jj represents the measured receiver transmission tracking error term on other ports, ET ji Represents the transmission tracking error term from the source calibration port to other ports.

[0016] Preferably, the measurement receiver error term for the source calibration port is calculated:

[0017] BT ii =ET ij ·RR jj ;

[0018] Where: i represents the source calibration port, j represents the receiving port, RRjj represents the reference receiver tracking error term of other ports, BT ii represents the measured receiver transmission tracking error term at the source calibration port, ET ij Represents the transmission tracking error term from other ports to the source calibration port.

[0019] Preferably, calculate the correction factors of other port sources: When the N-port calibration is performed through measurement, the mismatch error is very small, so the power meter reading value can be approximately expressed as:

[0020]

[0021] Where: a jM Indicates the receiver measurement value of other ports during the through measurement during the N-port calibration process, RR jj represents the reference receiver tracking error term of other ports, P jMea Indicates the calculated approximate power meter reading value;

[0022] SC j =P j -P jMea ;

[0023] Where: j represents other ports, SC j represents the source correction factor of other ports, P i Indicates the port power set for other ports, P jMea Indicates approximate power meter readings.

[0024] A source correction factor calculation system based on N-port calibration is used to implement the source correction factor calculation method based on N-port calibration described in the present application.

[0025] A storage medium, when running on a computer, executes the source correction factor calculation method based on N-port calibration described in the present application.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] The source correction factor calculation method proposed in this application is developed based on full N-port calibration. The calculation method is different from the method of directly using a power meter to calculate the source correction factor. The power meter reading is estimated by the through measurement of the N-port calibration and the receiver error term, which reduces the number of physical connections of the power meter. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 Figure 2 is the signal flow graph for source power calibration.

[0029] Figure 2 Signal flow graph for receiver calibration. DETAILED DESCRIPTION

[0030] The technical solution of the present application is described in detail below through specific embodiments and drawings. It should be understood that the embodiments of the present application and the specific features in the embodiments are detailed descriptions of the technical solution of the present application, rather than limitations on the technical solution of the present application, and the specific technical features may be combined with each other.

[0031] The source correction factor calculation method based on N-port calibration proposed in the patent of this invention is better than the traditional method. Its main advantage is that the source correction factors of all ports can be calculated through a physical connection of any port, which greatly reduces the operation repeatability and improves the calibration efficiency.

[0032] A source correction factor calculation method based on N-port calibration includes the following contents:

[0033] 1. Calculate the source correction factor for the source calibration port:

[0034] SC i =P i -P iMea

[0035] Where: i represents the source calibration port, SC i represents the source correction factor of the source calibration port, P i Indicates the port power of the source calibration port setting, P iMea Represents the power meter reading, which is the actual power at the source calibration port.

[0036] a iS Indicates the source signal of the source port; a iM represents the measurement signal of the reference receiver at the source port; a iA Indicates the actual measured value on the power meter.

[0037] 2. Calculate the receiver error term:

[0038] like Figure 1 As shown, firstly, the reference receiver tracking error term of the source calibration port is calculated based on the single-port calibration measurement data and the error term:

[0039]

[0040] Where: i represents the source calibration port, RR ii represents the reference receiver tracking error term at the source calibration port, P iMea Indicates the power meter reading, a iM Indicates the measured value on the power meter measurement receiver connected to the source calibration port. ES ii represents the source mismatch error at the source calibration port, Γ Sen Indicates the port reflection coefficient when the source calibration port is connected to the power meter.

[0041] like Figure 2 As shown, the reference receiver error terms and measurement receiver error terms of other calibration ports are then calculated:

[0042]

[0043] BT jj =ET ji ·RR ii

[0044] Where: i represents the source calibration port, j represents other ports, RR ii represents the reference receiver tracking error term at the source calibration port, RR jj represents the reference receiver tracking error term on other ports, ED ii represents the directivity error of the source calibration port, ER ii is the reflection tracking error at the source calibration port, ES ii is the source mismatch error at the source calibration port, ET ij represents the transmission tracking error term from other ports to the source calibration port, EL ij represents the load matching error term from other ports to the source calibration port, BT jj represents the measured receiver transmission tracking error term on other ports, ET ji represents the transmission tracking error from the source calibration port to other ports, S ii , S ij Both represent the transmission S parameters of the device under test, S ij , S jj Both represent the reflection S parameters of the device under test; b iM represents the measurement signal of the source port measurement receiver, b jM Represents the measurement signal of the measurement receiver of the receive port.

[0045] Finally, the measurement receiver error term at the source calibration port is calculated:

[0046] BT ii =ET ij ·RR jj

[0047] Where: i represents the source calibration port, j represents the receiving port, RR jj represents the reference receiver tracking error term of other ports, BT ii represents the measured receiver transmission tracking error term at the source calibration port, ET ij Represents the transmission tracking error term from other ports to the source calibration port.

[0048] At this point, all receiver error terms have been solved.

[0049] 3. Calculate the correction factors for other port sources:

[0050] When the N-port calibration is performed through the measurement, the mismatch error is small, so the power meter reading can be approximately expressed as:

[0051]

[0052] Where: a jM Indicates the receiver measurement value of other ports during the through measurement during the N-port calibration process, RR jj represents the reference receiver tracking error term of other ports, P jMea Indicates the calculated approximate power meter reading value.

[0053] SC j =P j -P jMea

[0054] Where: j represents other ports, SC j represents the source correction factor of other ports, P i Indicates the port power set for other ports, P jMea Indicates approximate power meter readings.

[0055] The method embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Those of ordinary skill in the art may understand and implement it without creative work.

[0056] The system is constructed to run the method of the present application. Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, by hardware. Based on this understanding, the above technical solution is essentially or the part that contributes to the prior art can be embodied in the form of a software product, which can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0057] It will be easily understood by those skilled in the art that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for calculating source correction factor based on N-port calibration, characterized in that: Connect a power meter to one VNA port, calculate the source correction factor of the source calibration port, then calculate all receiver error terms, and finally calculate the source correction factors of other ports through the through measurement of the N-port calibration and the receiver error terms.

2. The source correction factor calculation method based on N-port calibration according to claim 1 is characterized in that: The formula for calculating the source correction factor for the source calibration port is as follows: SC i =P i -P iMea ; Where: i represents the source calibration port, SC i represents the source correction factor of the source calibration port, P i Indicates the port power of the source calibration port setting, P iMea Represents the power meter reading, which is the actual power at the source calibration port.

3. The source correction factor calculation method based on N-port calibration according to claim 1 is characterized in that: Based on the one-port calibration measurement data and the error term, calculate the reference receiver tracking error term for the source calibration port: Where: RR ii represents the reference receiver tracking error term at the source calibration port, P iMea Indicates the power meter reading, a iM Indicates the measured value on the power meter measurement receiver connected to the source calibration port. ES ii represents the source mismatch error at the source calibration port, Γ Sen Indicates the port reflection coefficient when the source calibration port is connected to the power meter.

4. The source correction factor calculation method based on N-port calibration according to claim 3 is characterized in that: Calculate the reference receiver error terms and the measurement receiver error terms for the other calibration ports: BT jj =ET ji ·RR ii ; Where: i represents the source calibration port, j represents other ports, RR ii represents the reference receiver tracking error term at the source calibration port, RR jj represents the reference receiver tracking error term on other ports, ED ii represents the directivity error of the source calibration port, ER ii is the reflection tracking error at the source calibration port, ES ii is the source mismatch error at the source calibration port, ET ij represents the transmission tracking error term from other ports to the source calibration port, EL ij represents the load matching error term from other ports to the source calibration port, BT jj represents the measured receiver transmission tracking error term on other ports, ET ji Represents the transmission tracking error term from the source calibration port to other ports.

5. The source correction factor calculation method based on N-port calibration according to claim 4 is characterized in that: Calculate the measurement receiver error term for the source calibration port: BT ii =ET ij ·RR jj ; Where: i represents the source calibration port, j represents the receiving port, RR jj represents the reference receiver tracking error term of other ports, BT ii represents the measured receiver transmission tracking error term at the source calibration port, ET ij Represents the transmission tracking error term from other ports to the source calibration port.

6. The source correction factor calculation method based on N-port calibration according to claim 5, characterized in that: Calculate the correction factor for other port sources: When the N-port calibration is performed through the measurement, the mismatch error is very small, so the power meter reading can be approximately expressed as: Where: a jM Indicates the receiver measurement value of other ports during the through measurement during the N-port calibration process, RR jj represents the reference receiver tracking error term of other ports, P jMea Indicates the calculated approximate power meter reading value; SC j =P j -P jMea ; Where: j represents other ports, SC j represents the source correction factor of other ports, P i Indicates the port power set for other ports, P jMea Indicates approximate power meter readings.

7. A source correction factor calculation system based on N-port calibration, characterized in that: Used to implement the source correction factor calculation method based on N-port calibration as described in any one of claims 1 to 6.

8. A storage medium, characterized in that: When the storage medium is run on a computer, the source correction factor calculation method based on N-port calibration according to any one of claims 1 to 6 is executed.

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