Clamp coupling multi-port measured device de-embedding measurement calibration method

Abstract

The invention discloses a clamp coupling multi-port measured device de-embedding measurement calibration method, which comprises the following steps of: S1, measuring an S parameter of a clamp and a whole measured device, recording the S parameter as S ', measuring the S parameter of the clamp after the measured device is removed, and splicing the S parameter and recording the S parameter as Sfix; s2, listing an equation set of fixture input and output by utilizing Sfix, extracting odd-numbered lines, solving by adopting a Gaussian elimination method, substituting the odd-numbered lines into even-numbered lines of the equation set to obtain a coefficient matrix of DUT input and output, and recording the coefficient matrix as M; and S3, obtaining an S parameter of the DUT by using the coefficient matrix M and S ', and recording the S parameter as SDUT. According to the method, coupling between the clamps is considered in the calculation process, and the actual situation is better met. The method has no requirement on the number of DUT ports, and is suitable for a multi-port network with any number of ports.

Description

Technical Field

[0001] The present invention relates to the field of integrated circuit testing, and in particular to a de-embedding measurement and calibration method for a fixture-coupled multi-port device under test. Background Art

[0002] De-embedding is a measurement technique widely used in radio frequency (RF) and microwave circuit design. It is used to extract the true electrical characteristics of the device under test (DUT) from the measurement results, eliminating the influence of external factors such as test fixtures and connecting wires. De-embedding eliminates the effects of the fixture or external circuits on the device under test (DUT) by establishing a mathematical model of the fixture or external circuit (such as the S-parameter matrix), thus separating the true signal of the DUT from the measurement data containing interference. The core goal of de-embedding is to extract the true characteristic parameters of the DUT (such as S-parameters and impedance).

[0003] Most current de-embedding algorithms are only suitable for an even number of ports. They also measure the S parameters of only a single fixture and fail to consider the coupling between fixtures in multi-port scenarios. As chip process sizes continue to decrease and frequencies continue to increase, ignoring the coupling between fixtures can lead to inaccurate de-embedding results.

[0004] In 2015, Pu et al. proposed a de-embedding method for three-port networks in their article "A de-embedding technique of a three-port network with two ports coupled." This method considers the case where two of the three fixtures are coupled. In the same year, Guo et al. proposed a de-embedding method for three-port networks in their article "De-Embedding for Coupled Three-Port Devices," further accounting for coupling. However, for networks with more than three ports and considering coupling between fixtures, a suitable de-embedding method is currently lacking.

[0005] The Summary of the Invention introduces a series of simplified concepts, which are simplifications of existing technologies in the field and are further described in detail in the Detailed Description of the Invention. The Summary of the Invention is not intended to define the key features and essential features of the claimed technical solution, nor is it intended to determine the scope of protection of the claimed technical solution.

[0006] The technical problem to be solved by the present invention is to provide a fixture-coupled multi-port DUT de-embedding measurement and calibration method that has no restriction on the number of DUT ports, can be used in multi-port working conditions (more than 3 ports), and takes into account the fact that the inter-fixture coupling measurement results are more in line with the actual situation.

[0007] To solve the above technical problems, the present invention provides a fixture-coupled multi-port device under test de-embedding measurement and calibration method, comprising the following steps:

[0008] S1, measure the S parameters of the fixture and the device under test as a whole, recorded as S', measure the S parameters of the fixture after removing the device under test, and combine them, recorded as S fixture ;

[0009] S2, using S fixture List the equations for the fixture input and output, extract the odd rows and solve them using Gaussian elimination, then substitute them into the even rows of the equations to obtain the coefficient matrix for the DUT input and output, denoted as M;

[0010] S3, use the coefficient matrix M and S' to obtain the S parameters of the DUT, denoted as S DUT .

[0011] Preferably, the fixture-coupled multi-port device under test de-embedding measurement and calibration method is further improved, and step S1 includes:

[0012] The S of n fixtures after assembly is measured by the instrument fixture , list the input and output of the fixture and S fixture The relationship (1):

[0013]

[0014] a is the input vector of the side where the fixture is connected to the device under test, a' is the input vector of the side where the fixture is not connected to the device under test, b is the output vector of the side where the fixture is connected to the device under test, b' is the output vector of the side where the fixture is not connected to the device under test, and the matrix S is S fixture Write out the expansion of .

[0015] Preferably, the fixture-coupled multi-port device under test de-embedding measurement and calibration method is further improved, and step S2 includes:

[0016] Extract the odd rows of formula (1) and get formula (2):

[0017]

[0018] Use Gaussian elimination to solve the linear equations of formula (2) and get the solution of vector a, which is represented by vectors a' and b'. Substitute the solution of vector a into the even-numbered rows of formula (1), and then solve for vector b. The combination of a and b yields:

[0019]

[0020] M is the solved coefficient matrix.

[0021] Preferably, the fixture-coupled multi-port device under test de-embedding measurement and calibration method is further improved, and step S3 includes:

[0022] The M matrix is ​​simplified into 4 parts: A, B, C, and D according to the region:

[0023] Formula (3) can be written as Formula (4):

[0024]

[0025] Then vectors a and b can be expressed using the M matrix and a', b' as formula (5) and formula (6):

[0026] [b]=M c [a′]+M D [b′] formula (5);

[0027] [a]=M A [a′]+M B [b′] formula (6);

[0028]

[0029] Measure the DUT and fixture as a whole S'. Since the fixture and DUT are connected to each other, the output of the fixture is the input of the device under test on the side where the fixture and DUT are connected. DUT ]=[b], the input of the fixture is the output of the device under test [b DUT ]=[a];

[0030] According to equations (5), (6) and (7), the S parameters of the DUT are obtained:

[0031]

[0032] At this point, the S parameters of the DUT (S DUT ), complete the de-embedding of the multi-port network under fixture coupling;

[0033] Among them, MA, MB, MC and MD are the four parts of the M matrix that have been obtained, and S′ is the overall S parameter that has been measured.

[0034] The present invention provides a computer-readable storage medium, which stores a computer program therein. When the computer program is executed, it is used to implement the steps of any one of the above-mentioned fixture-coupled multi-port device under test de-embedding measurement and calibration methods.

[0035] Compared to existing de-embedding techniques, this invention takes into account the coupling between fixtures during the calculation process, which is more realistic. This invention uses the S-parameters of the fixtures to construct the matrix, without limiting the number of DUT ports, and is applicable to multi-port networks with any number of ports. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The drawings herein are intended to illustrate the general characteristics of methods, structures, and / or materials used in certain exemplary embodiments of the present invention, supplementing the descriptions in the specification. However, the drawings herein are schematic diagrams not drawn to scale and may not accurately reflect the precise structure or performance characteristics of any given embodiment. The drawings herein should not be interpreted as defining or limiting the range of values ​​or properties encompassed by the exemplary embodiments of the present invention. The present invention is further described in detail below in conjunction with the drawings and specific embodiments:

[0037] Figure 1 It is a schematic diagram of a multi-port network. DETAILED DESCRIPTION

[0038] The following describes the embodiments of the present invention through specific embodiments. Those skilled in the art can fully understand the other advantages and technical effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through different specific embodiments, and the details in this specification can also be applied based on different viewpoints, and various modifications or changes can be made without departing from the overall design concept of the invention. It should be noted that, in the absence of conflict, the following embodiments and the features therein can be combined with each other. The following exemplary embodiments of the present invention can be implemented in a variety of different forms and should not be interpreted as being limited to the specific embodiments described herein. It should be understood that these embodiments are provided to make the disclosure of the present invention thorough and complete, and to fully convey the technical solutions of these exemplary embodiments to those skilled in the art. It should be understood that when an element is referred to as being "connected" or "coupled" to another element, the element can be directly connected or coupled to the other element, or there can be an intermediate element. In contrast, when an element is referred to as being "directly connected" or "directly coupled" to another element, there is no intermediate element. In all figures, the same figure numbers always represent the same elements.

[0039] First embodiment;

[0040] The present invention provides a fixture-coupled multi-port device under test de-embedding measurement and calibration method, comprising the following steps:

[0041] S1, measure the S parameters of the fixture and the device under test as a whole, recorded as S', measure the S parameters of the fixture after removing the device under test, and combine them, recorded as S fixture ; The S of n fixtures after assembly is measured by the instrumentfixture , list the input and output of the fixture and S fixture The relationship (1):

[0042]

[0043] a is the input vector of the side where the fixture is connected to the device under test, a' is the input vector of the side where the fixture is not connected to the device under test, b is the output vector of the side where the fixture is connected to the device under test, b' is the output vector of the side where the fixture is not connected to the device under test, and the matrix S is S fixture Write out the expansion of

[0044] S2, using S fixture List the equations for the fixture input and output, extract the odd rows and solve them using Gaussian elimination, and then substitute them into the even rows of the equations to obtain the coefficient matrix for the DUT input and output, denoted as M; extract the odd rows of equation (1) to obtain equation (2):

[0045]

[0046] Use Gaussian elimination to solve the linear equations of formula (2) and get the solution of vector a, which is represented by vectors a' and b'. Substitute the solution of vector a into the even-numbered rows of formula (1), and then solve for vector b. The combination of a and b yields:

[0047]

[0048] M is the solved coefficient matrix;

[0049] S3, simplify the M matrix into 4 parts: A, B, C, and D according to the region: Formula (3) can be written as Formula (4):

[0050]

[0051] Then vectors a and b can be expressed using the M matrix and a', b' as formula (5) and formula (6):

[0052] [b]=M c [a′]+M D [b′] formula (5);

[0053] [a]=M A [a′]+M B [b′] formula (6);

[0054]

[0055] Measure the DUT and fixture as a whole S', the output of the fixture is the input of the device under test [a DUT ]=[b], the input of the fixture is the output of the device under test [bDUT ]=[a];

[0056] According to equations (5), (6) and (7), the S parameters of the DUT are obtained:

[0057] Solve the DUT's S parameters (S DUT ), complete the de-embedding of the multi-port network under fixture coupling;

[0058] Among them, MA, MB, MC and MD are the four parts of the M matrix that have been obtained, and S′ is the overall S parameter that has been measured.

[0059] Second embodiment;

[0060] The present invention provides a computer-readable storage medium having a computer program stored therein. When the computer program is executed, the computer program is used to implement the steps of the fixture-coupled multi-port device under test de-embedding measurement calibration method described in the first embodiment.

[0061] The computer-readable medium includes permanent and non-permanent, removable and non-removable media that can implement information storage by any method or technology. The information can be computer-readable instructions, data structures, program modules or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disc read-only memory (CD-ROM), digital versatile disc (DVD) or other optical storage, magnetic cassettes, tape disk storage or other magnetic storage devices or any other non-transmission media that can be used to store information that can be accessed by a computing device. As defined herein, computer-readable media does not include non-transitory media such as modulated data signals and carrier waves.

[0062] Unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will also be understood that, unless expressly defined herein, terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant art, rather than being interpreted in an idealized or overly formal sense.

[0063] The present invention has been described in detail above by way of specific embodiments and examples, but these do not constitute limitations of the present invention. Without departing from the principles of the present invention, those skilled in the art may make many variations and improvements, which should also be considered within the scope of protection of the present invention.

Claims

1. A fixture-coupled multi-port device under test de-embedding measurement and calibration method, characterized in that: The following steps are involved: S1, measure the S parameters of the fixture and the device under test as a whole, recorded as S', measure the S parameters of the fixture after removing the device under test, and combine them, recorded as S fixture ; S2, using S fixture List the equations for the fixture input and output, extract the odd rows and solve them using Gaussian elimination, then substitute them into the even rows of the equations to obtain the coefficient matrix for the DUT input and output, denoted as M; S3, use the coefficient matrix M and S' to obtain the S parameters of the DUT, denoted as S DUT .

2. The fixture-coupled multi-port device under test de-embedding measurement and calibration method according to claim 1, wherein: Executing step S1 includes: The instrument measures the S after n fixtures are assembled. fixture , list the input and output of the fixture and S fixture The relationship (1): a is the input vector of the side where the fixture is connected to the device under test, a' is the input vector of the side where the fixture is not connected to the device under test, b is the output vector of the side where the fixture is connected to the device under test, b' is the output vector of the side where the fixture is not connected to the device under test, and the matrix S is S fixture Write out the expansion of .

3. The fixture-coupled multi-port device under test de-embedding measurement and calibration method according to claim 2, wherein: Executing step S2 includes: Extract the odd rows of formula (1) and get formula (2): Use Gaussian elimination to solve the linear equations of formula (2) and get the solution of vector a, which is represented by vectors a' and b'. Substitute the solution of vector a into the even-numbered rows of formula (1), and then solve for vector b. The combination of a and b yields: M is the solved coefficient matrix.

4. The fixture-coupled multi-port device under test de-embedding measurement and calibration method according to claim 3, wherein: Executing step S3 includes: The M matrix is ​​simplified into 4 parts: A, B, C, and D according to the region: Formula (3) can be written as Formula (4): Then vectors a and b can be expressed using the M matrix and a', b' as formula (5) and formula (6): [b]=M c [a′]+M D [b′] formula (5); [a] = M A [a'] + M B [b'] Equation (6); Measure the DUT and fixture as a whole S', the output of the fixture is the input of the device under test [a DUT ]=[b], the input of the fixture is the output of the device under test [b DUT ]=[a]; According to equations (5), (6) and (7), the S parameters of the DUT are obtained: Among them, MA, MB, MC and MD are the four parts of the M matrix that have been obtained, and S′ is the overall S parameter that has been measured.

5. A computer-readable storage medium, characterized in that: A computer program is stored therein, and when the computer program is executed, it is used to implement the steps of the fixture-coupled multi-port device under test de-embedding measurement and calibration method according to any one of claims 1 to 4.

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