Method, device and computer storage medium for obtaining S parameters of two-port network

Abstract

The present invention provides a method, device and computer storage medium for obtaining the S parameters of a two-port network. The method comprises the following steps: connecting two non-coaxial ports of the two-port network to obtain a combined network; obtaining the S parameters of the combined network; determining the T parameters of the combined network; determining the T parameters T of the two-port network A ; Determine the S parameter S of the two-port network A This solution can obtain the S parameters of a two-port network with a coaxial port at one end and a non-coaxial port at the other end, solving the technical problem that the S parameters of such a two-port network cannot be directly measured using an instrument. It is no longer necessary to design a measurement fixture to match the non-coaxial port, thus reducing the test cost.

Description

Technical Field

[0001] The present invention relates to the field of microwave measurement technology, and in particular to a method, a device and a computer storage medium for obtaining S parameters of a two-port network. Background Art

[0002] For microwave two-port networks, scattering parameters (S parameters), transmission parameters (T parameters), impedance parameters (Z parameters), and hybrid parameters (H parameters) are commonly used to characterize the characteristics of the network. In the field of high-frequency microwaves, scattering parameters (S parameters) based on the amplitude and phase of the incident wave and the reflected wave can fully reflect the performance of the microwave network, facilitate the analysis of complex systems, and are widely used. Currently, in the microwave field, the most commonly used method for measuring and analyzing microwave networks is to use a vector network analyzer to measure the S parameters of the network, and the simulation of microwave circuits is also mostly performed using S parameters.

[0003] Using a vector network analyzer to measure the S parameters of a network has the advantages of being simple, convenient, and highly accurate. However, since the measurement ports of a vector network analyzer are all coaxial ports, for networks with non-coaxial ports, due to port mismatch, it may not be possible to measure or the corresponding measurement fixture must be matched. For example, if one end of a two-port network is a coaxial port and the other end is a non-coaxial port, the existing vector network analyzer cannot be used to directly measure the S parameters of the network. Summary of the invention

[0004] The present invention provides a method, device and computer storage medium for obtaining S parameters of a two-port network, so as to solve the technical problem that when one end of the two-port network is a coaxial port and the other end is a non-coaxial port, the S parameters of the network cannot be directly measured by an instrument.

[0005] In order to solve the above technical problems, the present invention provides a method for obtaining S parameters of a two-port network, wherein the two-port network includes a coaxial port and a non-coaxial port, and the method includes the following steps:

[0006] Connecting the non-coaxial ports of the two-port networks to obtain a combined network;

[0007] Obtaining S parameters of the combined network;

[0008] According to the relationship between the S parameter of the combined network, the T parameter of the combined network and the S parameter of the combined network Determine the T parameter of the combined network and obtain Among them, the S parameter of the combined network is The T parameter of the combined network is

[0009] According to the T parameter of the combined network, |T|=T A11 T A22 -T A12 T A21 =1Determine the T parameter T of the two-port network A ,in,

[0010] According to the relationship between the T parameter of the two-port network, the S parameter of the two-port network and the T parameter of the two-port network Determine the S parameter S of the two-port network A , where the S parameter of the two-port network is

[0011] Optionally, the obtaining of the S parameters of the combined network specifically includes: obtaining the S parameters of the combined network using a vector network analyzer.

[0012] The present invention also provides a device for obtaining S parameters of a two-port network, wherein the two-port network includes a coaxial port and a non-coaxial port, and includes the following modules:

[0013] A matching module, used for connecting the non-coaxial ports of the two-port networks to obtain a combined network;

[0014] An acquisition module, used for acquiring S parameters of the combined network;

[0015] A first determining module is used to determine the relationship between the S parameter of the combined network, the T parameter of the combined network and the S parameter of the combined network. Determine the T parameter of the combined network and obtain Among them, the S parameter of the combined network is S The T parameter of the combined network is

[0016] The second determining module is used to determine the T parameter of the combined network according to the |T|=T A11 T A22 -T A12 T A21 =1Determine the T parameter T of the two-port network A ,in,

[0017] The third determining module is used to determine the relationship between the T parameter of the two-port network, the S parameter of the two-port network and the T parameter of the two-port network. Determine the S parameter S of the two-port network A, where the S parameter of the two-port network is

[0018] Optionally, the acquisition module is specifically used to: acquire S parameters of the combined network using a vector network analyzer.

[0019] The present invention also provides a computer storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, can implement any one of the above-mentioned methods for obtaining S parameters of a two-port network.

[0020] The present invention provides a method, device and computer storage medium for obtaining S parameters of a two-port network, which can obtain the S parameters of a two-port network with a coaxial port at one end and a non-coaxial port at the other end, thereby solving the technical problem that the S parameters of such a two-port network cannot be directly measured using an instrument, and it is no longer necessary to design a measurement fixture for matching the non-coaxial port, thereby reducing the test cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a flow chart of a method for obtaining S parameters of a two-port network provided by an embodiment of the present invention.

[0022] Figure 2 It is a schematic diagram of scattering parameters of a two-port network provided by an embodiment of the present invention.

[0023] Figure 3 yes Figure 2 The corresponding signal flow graph.

[0024] Figure 4 A signal flow diagram of two two-port networks cascaded according to an embodiment of the present invention.

[0025] Figure 5 It is a schematic diagram of a structure of two two-port networks cascaded according to an embodiment of the present invention. DETAILED DESCRIPTION

[0026] In order to make the purpose, advantages and features of the present invention clearer, the following is a further detailed description of a method, device and computer storage medium for obtaining S parameters of a two-port network proposed by the present invention in conjunction with the accompanying drawings. It should be noted that the accompanying drawings are all in a very simplified form and are not in precise proportions, and are only used to conveniently and clearly assist in explaining the purpose of the embodiments of the present invention.

[0027] In the description of the present invention, the terms "first", "second", etc. are added for the convenience of description and reference, and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined by the terms "first", "second", etc. may explicitly or implicitly include one or more of the features.

[0028] like Figure 1 As shown, this embodiment provides a method for obtaining S parameters of a two-port network, wherein the two-port network includes a coaxial port and a non-coaxial port, and the method includes the following steps:

[0029] S1. Connect the non-coaxial ports of the two-port networks to obtain a combined network.

[0030] like Figure 2 and Figure 3 As shown, according to the definition of the S parameters of the two-port network, there is the following relationship:

[0031]

[0032] In the formula, a represents the voltage incident wave of the port, b represents the voltage reflected wave of the port, and a 1 represents the voltage incident wave at port 1, b 1 represents the voltage reflection wave at port 1, a 2 represents the voltage incident wave at port 2, b 2 Represents the voltage reflection wave of the 2-port; the second number in the subscript of each element in the S parameter represents the incident port, and the first number represents the detection port, such as S 11 Represents the S parameter between the incident port of port 1 and the detection port of port 1. The meanings of other S parameters are similar. S parameters include 4 elements S 11 , S 12 , S 21 , S 22 .

[0033] For the transmission parameter (T parameter), its definition and relationship with the S parameter are as follows:

[0034]

[0035]

[0036] The subscript meaning of the T parameter corresponds to the subscript meaning of the S parameter. The T parameter includes 4 elements: 11 , T 12 , T 21 , T 22 .

[0037] For the case of two networks cascaded, the signal flow graph is as follows Figure 4 As shown. When port 2 of the N1 network and port 1 of the N2 network are fully matched, b′ 2 =a″ 1 , a′ 2 =b″ 1 .

[0038] Therefore, we can get the following formula

[0039]

[0040] It can be seen that for the cascade network, the T parameter of the entire network (i.e., the combined network) has the following relationship with T′ and T″ of the previous and next two-stage networks:

[0041]

[0042] like Figure 5 As shown, in this embodiment, two identical asymmetric reversible networks A and B to be tested are used, wherein port 1 of A and port 2 of B are coaxial ports, port 2 of A and port 1 of B are non-coaxial ports but can match each other, and networks A and B are cascaded, and the S parameters of networks A and B are the same.

[0043] S2. Obtain the S parameters of the combined network. The S parameters of the combined network may be obtained using a vector network analyzer, which may directly obtain the S parameters of the combined network. In other embodiments, other instruments may also be used to obtain the S parameters of the combined network.

[0044] S3, according to the relationship between the S parameter of the combined network, the T parameter of the combined network and the S parameter of the combined network Determine the T parameter of the combined network and obtain Among them, the S parameter of the combined network is The T parameter of the combined network is

[0045] S4, according to the T parameter of the combined network, |T|=T A11 T A22 -T A12 T A21 =1Determine the T parameter T of the two-port network A ,in,

[0046] Since networks A and B are asymmetric reversible networks with matching non-coaxial ports, when port 2 of network A and port 1 of network B are directly connected, it can be regarded as a cascade of two networks, and the following relationship exists:

[0047] S A11 =S B22 , S A22 =S B11 , S A21 =S A12 =S B21 =SB12 Formula 6

[0048] From the relationship between S parameters and T parameters (i.e., Formula 3), we can get:

[0049] T A11 =T B11 , T A12 =-T B21 , T A21 =-T B12 , T A22 =T B22 Formula 7

[0050] Therefore, the T parameter of the entire network is

[0051]

[0052] After the S parameters of the entire network are measured by the vector network analyzer, they can be converted into T parameters through formula 3, expressed by constants a, b, and c, that is, T 11 =a,T 12 =-T 21 =b,T 22 =c, from which we can get the following equation:

[0053]

[0054] Since the entire network is reversible, its T parameter has the following characteristics:

[0055] |T|=T A11 T A22 -T A12 T A21 =1 Formula 10

[0056] According to the above formula 9 and formula 10, the T parameter T of network A can be calculated. A , and then the T parameter T of the B network can be calculated by formula 7 B .

[0057] S5, according to the relationship between the T parameter of the two-port network, the S parameter of the two-port network and the T parameter of the two-port network Determine the S parameter S of the two-port network A , where the S parameter of the two-port network is

[0058] The present embodiment provides a method for obtaining the S parameters of a two-port network, which can obtain the S parameters of a two-port network with one end being a coaxial port and the other end being a non-coaxial port, thereby solving the technical problem that the S parameters of such a two-port network cannot be directly measured using an instrument. It is no longer necessary to design a measurement fixture for matching the non-coaxial port, thereby reducing the test cost.

[0059] As a specific embodiment, take two identical reversible two-port networks as an example, whose S parameters (linear expression) are The conversion to T parameter is Using the above method to split, we get the T of network A A The parameters are Further conversion to S A The parameters are Realize the splitting of network S parameters.

[0060] Optionally, the obtaining of the S parameters of the combined network specifically includes: obtaining the S parameters of the combined network using a vector network analyzer. The S parameters of the combined network can be directly obtained using a vector network analyzer without conversion.

[0061] Based on the same technical concept as the above method for obtaining S parameters of a two-port network, this embodiment further provides a device for obtaining S parameters of a two-port network, wherein the two-port network includes a coaxial port and a non-coaxial port, and includes the following modules:

[0062] A matching module, used for connecting the non-coaxial ports of the two-port networks to obtain a combined network;

[0063] An acquisition module, used for acquiring S parameters of the combined network;

[0064] A first determining module is used to determine the relationship between the S parameter of the combined network, the T parameter of the combined network and the S parameter of the combined network. Determine the T parameter of the combined network and obtain Among them, the S parameter of the combined network is S The T parameter of the combined network is

[0065] The second determining module is used to determine the T parameter of the combined network according to the |T|=T A11 T A22 -T A12 T A21 =1Determine the T parameter T of the two-port network A ,in,

[0066] The third determining module is used to determine the relationship between the T parameter of the two-port network, the S parameter of the two-port network and the T parameter of the two-port network. Determine the S parameter S of the two-port network A , where the S parameter of the two-port network is

[0067] The present embodiment provides a device for obtaining the S parameters of a two-port network, which can obtain the S parameters of a two-port network with a coaxial port at one end and a non-coaxial port at the other end, thereby solving the technical problem that the S parameters of such a two-port network cannot be directly measured using an instrument. It is no longer necessary to design a measurement fixture for matching the non-coaxial port, thereby reducing the test cost.

[0068] Optionally, the acquisition module is specifically used to: acquire the S parameters of the combined network using a vector network analyzer. The S parameters of the combined network can be directly acquired using a vector network analyzer without conversion.

[0069] Based on the above method for obtaining S parameters of a two-port network, this embodiment further provides a computer storage medium on which a computer program is stored. When the computer program is executed by a processor, it can implement the method for obtaining S parameters of a two-port network described in any of the above embodiments.

[0070] A computer storage medium provided in this embodiment can obtain the S parameters of a two-port network with a coaxial port at one end and a non-coaxial port at the other end, thereby solving the technical problem that the S parameters of such a two-port network cannot be directly measured using an instrument. It is no longer necessary to design a measurement fixture for matching the non-coaxial port, thereby reducing the test cost.

[0071] The readable storage medium can be a tangible device that can keep and store the instructions used by the instruction execution device, such as but not limited to an electrical storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device or any suitable combination of the above. The more specific example (non-exhaustive list) of the readable storage medium includes: a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), a static random access memory (SRAM), a portable compact disk read-only memory (CD-ROM), a digital versatile disk (DVD), a memory stick, a floppy disk, a mechanical encoding device, such as a punch card or a convex structure in a groove on which instructions are stored, and any suitable combination of the above. The computer program described here can be downloaded from the readable storage medium to each computing / processing device, or downloaded to an external computer or external storage device through a network, such as the Internet, a local area network, a wide area network and / or a wireless network. The network can include copper transmission cables, optical fiber transmission, wireless transmission, routers, firewalls, switches, gateway computers and / or edge servers. The network adapter card or network interface in each computing / processing device receives the computer program from the network and forwards the computer program for storage in a readable storage medium in each computing / processing device. The computer program for performing the operation of the present invention may be an assembly instruction, an instruction set architecture (ISA) instruction, a machine instruction, a machine-dependent instruction, a microcode, a firmware instruction, a state setting data, or a source code or object code written in any combination of one or more programming languages, including object-oriented programming languages ​​such as Smalltalk, C++, etc., and conventional procedural programming languages ​​such as "C" language or similar programming languages. The computer program may be executed entirely on the user's computer, partially on the user's computer, as an independent software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the case of a remote computer, the remote computer may be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (e.g., using an Internet service provider to connect through the Internet). In some embodiments, by utilizing the state information of a computer program to personalize an electronic circuit, such as a programmable logic circuit, a field programmable gate array (FPGA), or a programmable logic array (PLA), the electronic circuit can execute computer-readable program instructions to implement various aspects of the present invention.

[0072] In summary, the present invention provides a method, device and computer storage medium for obtaining S parameters of a two-port network, which can obtain the S parameters of a two-port network with a coaxial port at one end and a non-coaxial port at the other end, thereby solving the technical problem that the S parameters of such a two-port network cannot be directly measured using an instrument. It is no longer necessary to design a measurement fixture for matching the non-coaxial port, thereby reducing the test cost.

[0073] The above description is only a description of the preferred embodiments of the present invention, and is not intended to limit the scope of the present invention. Any changes or modifications made by a person skilled in the art based on the above disclosure shall fall within the protection scope of the present invention.

Claims

1. A method for obtaining S parameters of a two-port network, characterized in that: The two-port network includes a coaxial port and a non-coaxial port, and the method includes the following steps: Connecting the non-coaxial ports of the two-port networks to obtain a combined network; Obtaining S parameters of the combined network; According to the relationship between the S parameter of the combined network, the T parameter of the combined network and the S parameter of the combined network Determine the T parameter of the combined network and obtain Among them, the S parameter of the combined network is The T parameter of the combined network is According to the T parameter of the combined network, |T|=T A11 T A22 -T A12 T A21 =1Determine the T parameter T of the two-port network A ,in, According to the relationship between the T parameter of the two-port network, the S parameter of the two-port network and the T parameter of the two-port network Determine the S parameter S of the two-port network A , where the S parameter of the two-port network is Among them, T is determined according to the following relationship 11 , T 12 , T 21 and T 22 The expression of The second number in the subscript of each element in the S parameter represents the incident port, and the first number represents the detection port. 11 represents the S parameter between the incident port of port 1 and the detection port of port 1, S 21 represents the S parameter between the incident port of port 1 and the detection port of port 2, S 12 represents the S parameter between the incident port of port 2 and the detection port of port 1, S 22 Represents the S parameter between the 2-port incident port and the 2-port detection port.

2. A method for obtaining S parameters of a two-port network as claimed in claim 1, characterized in that: The obtaining of the S parameters of the combined network specifically includes: obtaining the S parameters of the combined network using a vector network analyzer.

3. A device for obtaining S parameters of a two-port network, characterized in that: The two-port network includes a coaxial port and a non-coaxial port, and includes the following modules: A matching module, used for connecting the non-coaxial ports of the two-port networks to obtain a combined network; An acquisition module, used for acquiring S parameters of the combined network; A first determining module is used to determine the relationship between the S parameter of the combined network, the T parameter of the combined network and the S parameter of the combined network. Determine the T parameter of the combined network and obtain Among them, the S parameter of the combined network is The T parameter of the combined network is The second determining module is used to determine the T parameter of the combined network according to the Determine the T parameter T of the two-port network A ,in, The third determining module is used to determine the relationship between the T parameter of the two-port network, the S parameter of the two-port network and the T parameter of the two-port network. Determine the S parameter S of the two-port network A , where the S parameter of the two-port network is Among them, T is determined according to the following relationship 11 , T 12 , T 21 and T 22 The expression of The second number in the subscript of each element in the S parameter represents the incident port, and the first number represents the detection port. 11 represents the S parameter between the incident port of port 1 and the detection port of port 1, S 21 represents the S parameter between the incident port of port 1 and the detection port of port 2, S 12 represents the S parameter between the incident port of port 2 and the detection port of port 1, S 22 Represents the S parameter between the 2-port incident port and the 2-port detection port.

4. A device for obtaining S parameters of a two-port network as claimed in claim 3, characterized in that: The acquisition module is specifically used to: use a vector network analyzer to acquire the S parameters of the combined network.

5. A computer storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, it can implement a method for obtaining S parameters of a two-port network as described in any one of claims 1 to 2.

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