A vector network analyzer and port expansion device

Abstract

The present invention discloses a vector network analyzer and a port extension device, which belongs to the technical field related to electronic measuring equipment, including a vector network analyzer and a port extension device for expanding the same. The vector network analyzer includes a first port, an excitation source, a first directional coupler, a direct input interface, a one-to-many switch, a one-to-two switch, a reference receiver, a measurement receiver, a reference extension interface, and a measurement extension interface. The port extension device includes a second port, a second directional coupler, a direct control switch, a reference receiving switch, a measurement receiving switch, and a control module. The direct input interface is connected to the direct output interface, the reference output interface is connected to the reference extension interface, and the measurement output interface is connected to the measurement extension interface to increase the test port. The present invention can meet the measurement requirements when the demand for the number of test ports is high, and can reduce the test performance loss during expansion.

Description

Technical Field

[0001] The present invention relates to the technical field related to electronic measuring equipment, and in particular to a vector network analyzer and a port expansion device. Background Art

[0002] With the evolution of communication protocols, Massive-MIMO (massive multiple-input multiple-output) has become a major solution to increase the bandwidth of information transmission channels. The test requirements for the multi-port array antennas used in this solution will increase, and multi-port vector network analyzers are required for testing. In addition, vector network analyzers are sometimes used in the fields of radar, electronic countermeasures, artificial intelligence, etc.

[0003] The vector network analyzers currently used usually have 2 or 4 ports. With the development of technology, the demand for the number of test ports is increasing, so port expansion is needed. The existing technology mainly includes the following solutions for expanding the number of ports of vector network analyzers: the first is to directly cascade multiple vector network analyzers, which requires a large rack space and is costly, and is not common in actual work; the second is to directly cascade multiple vector network analyzers, which requires a large rack space and is costly, and is not common in actual work; the second is to directly cascade multiple vector network analyzers, which requires a large rack space and is costly, and is not common in actual work; the third is to directly cascade multiple vector network analyzers, which requires a large rack space and is costly, and is not common in actual work; the fourth is to cascade multiple vector network analyzers, which requires a large rack space and is costly, and is not common in actual work; the fourth is to cascade multiple vector network analyzers, which requires a large rack space and is costly, and is not common in actual work; the fifth ... Figure 5 As shown, the switch matrix is ​​connected to the port of the vector network analyzer. However, this method requires occupying the port of the vector network analyzer itself, and if the switch device and the device under test are directly connected, the switches in the switch matrix will produce insertion loss, which will deteriorate the directivity and dynamic range of the vector network analyzer. The deterioration of directivity will affect the measurement of the reflection coefficient, and the deterioration of the dynamic range will affect the measurement of the transmission coefficient. Therefore, the test performance will deteriorate after using the switch matrix. Summary of the invention

[0004] In view of the above-mentioned defects, the present invention provides a vector network analyzer and a port expansion device, which can meet the measurement needs when the demand for the number of test ports is high, and can reduce the test performance loss during expansion.

[0005] In order to achieve the purpose of the present invention, the following technologies are proposed:

[0006] A vector network analyzer, comprising:

[0007] n / 2 first ports;

[0008] Motivational source;

[0009] A one-to-many switch, comprising an input terminal and n output terminals, n≥4, and n is an even number, the input terminal of the one-to-many switch is connected to an excitation source, the n / 2 output terminals are respectively connected to a first directional coupler, and the other n / 2 output terminals are respectively connected to a direct output interface, and each first directional coupler is respectively connected to each first port;

[0010] n one-to-two switches are divided into two groups, each group has n / 2 switches, the one-to-two switches include an output end and two input ends, one input end of each one-to-two switch in the first group is connected to each first directional coupler, and one input end of each one-to-two switch in the second group is also connected to each first directional coupler;

[0011] n / 2 reference receivers are respectively connected to the output ends of the one-to-two switches of the first group;

[0012] n / 2 measurement receivers are respectively connected to the output ends of the one-to-two switches of the second group;

[0013] n / 2 reference expansion interfaces are respectively connected to the other input end of each one-to-two switch of the first group;

[0014] The n / 2 measurement expansion interfaces are respectively connected to the other input end of each one-to-two switch of the second group.

[0015] A port expansion device, used for expanding the port of the above-mentioned vector network analyzer, comprising:

[0016] m second ports, m≥n / 2, each second port is connected to a second directional coupler;

[0017] n / 2 direct-connection control switches, each of which includes an input terminal and at least one output terminal, the input terminal of the direct-connection control switch is connected to a direct-connection input interface, the direct-connection input interface is connected to a direct-connection output interface, and each output terminal of the direct-connection control switch is connected to a second directional coupler;

[0018] n / 2 reference receiving switches, the reference receiving switches comprising an input end and at least one output end, the input end of the reference receiving switch being connected to a reference output interface provided on the second rear panel, the reference output interface being connected to the reference extension interface, and each output end of the reference receiving switch being connected to a second directional coupler;

[0019] n / 2 measurement receiving switches, wherein the measurement receiving switches include an input end and at least one output end, the input end of the measurement receiving switch is connected to a measurement output interface provided on the second rear panel, the measurement output interface is connected to the measurement expansion interface, and each output end of the measurement receiving switch is respectively connected to a second directional coupler.

[0020] The beneficial effects of this technical solution are:

[0021] 1. The vector network analyzer has independent direct output interface, reference expansion interface, and measurement expansion interface. The use of these interfaces is not mutually exclusive with the use of the first port of the vector network analyzer itself, so that when the first ports are available, the second ports of the vector network analyzer are also available after connecting the port expansion device. Therefore, more ports can be obtained after expansion, that is, a total of n / 2+m ports are available, which meets the measurement needs when the demand for the number of test ports is high.

[0022] 2. Both the vector network analyzer and the port expansion device use directional couplers instead of switch matrices. The switch devices and the device under test are not directly connected. Instead, a directional coupler is set in the middle to avoid the deterioration of the directivity due to the switch insertion loss. It has good directivity, can ensure the measurement accuracy of the reflection coefficient, and improve the test performance when adding ports. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 A circuit schematic diagram of a vector network analyzer when n=4 in an embodiment of the present application is shown.

[0024] Figure 2 A circuit schematic diagram of a port expansion device according to an embodiment of the present application is shown.

[0025] Figure 3 A circuit schematic diagram showing the connection between a vector network analyzer and a port expansion device when n=4 and m=3 according to an embodiment of the present application is shown.

[0026] Figure 4 The flowchart of the SCPI parser in the embodiment of the present application is shown.

[0027] Figure 5 The invention shows a circuit schematic diagram of an existing vector network analyzer expanded by a switch matrix. DETAILED DESCRIPTION

[0028] The present application is further described below in conjunction with the accompanying drawings and embodiments.

[0029] like Figure 1 , Figure 3 A vector network analyzer shown includes a first chassis, an excitation source, a one-to-many switch, a one-to-two switch, a reference receiver, a measurement receiver, a reference expansion interface, and a measurement expansion interface.

[0030] The first chassis includes a first front panel and a first rear panel, and the first front panel is provided with n / 2 first ports.

[0031] The excitation source and the one-to-many switch are both arranged in the first chassis. The one-to-many switch includes an input terminal and n output terminals, n≥4, and n is an even number. The input terminal of the one-to-many switch is connected to the excitation source, and the n / 2 output terminals are respectively connected to a first directional coupler, and the other n / 2 output terminals are respectively connected to a direct output interface arranged on the first rear panel, and each first directional coupler is respectively connected to each first port.

[0032] There are n one-to-two switches, all of which are arranged in the first chassis and divided into two groups, each group has n / 2 switches, the one-to-two switches include an output end and two input ends, one input end of each one-to-two switch of the first group is respectively connected to each first directional coupler, and one input end of each one-to-two switch of the second group is also respectively connected to each first directional coupler.

[0033] The number of reference receivers is n / 2, all of which are arranged in the first chassis and are respectively connected to the output ends of each one-to-two switch of the first group.

[0034] The number of the measuring receivers is n / 2, all of which are arranged in the first chassis and are respectively connected to the output ends of each one-to-two switch of the second group.

[0035] The number of reference expansion interfaces is n / 2, which are arranged on the first rear panel and are respectively connected to the other input end of each one-to-two switch of the first group.

[0036] The number of the measurement expansion interfaces is n / 2, which are arranged on the first rear panel and are respectively connected to the other input end of each one-to-two switch of the second group.

[0037] Vector network analyzer specific example: Figure 1 As shown, n=4, that is, the number of the first port, the first directional coupler, the direct output interface, the reference receiver, the measurement receiver, the reference extension interface, and the measurement extension interface are all 2, and the one-to-many switches are all arranged in the first chassis, including an input terminal and 4 output terminals, and the number of one-to-two switches is 4, 2 in each group.

[0038] The vector network analyzer can be easily expanded, such as Figure 3 The specific expansion results are described later.

[0039] like Figure 2 , Figure 3 A port expansion device is shown, which is used to expand the port of the above-mentioned vector network analyzer, and includes a second chassis, a direct connection control switch, a reference receiving switch, a measurement receiving switch, and a control module.

[0040] like Figure 2A schematic diagram of a circuit for a port expansion device in a general situation is shown, wherein the ellipsis indicates that there may be multiple identical devices in the middle.

[0041] The second chassis includes a second front panel and a second rear panel, the second front panel is provided with m second ports, m ≥ n / 2, generally m does not exceed 32, and each of the m second ports is respectively connected to a second directional coupler provided in the second chassis, and the second rear panel is provided with a network port;

[0042] The number of direct-connection control switches is n / 2, all of which are arranged in the second chassis, the direct-connection control switch includes an input end and at least one output end, the input end of the direct-connection control switch is connected to a direct-connection input interface arranged on the second rear panel, the direct-connection input interface is connected to the direct-connection output interface, and each output end of the direct-connection control switch is respectively connected to a second directional coupler;

[0043] The number of reference receiving switches is n / 2, all of which are arranged in the second chassis, the reference receiving switch includes an input end and at least one output end, the input end of the reference receiving switch is connected to a reference output interface arranged on the second rear panel, the reference output interface is connected to the reference extension interface, and each output end of the reference receiving switch is respectively connected to a second directional coupler;

[0044] The number of the measurement receiving switches is n / 2, all of which are arranged in the second chassis, the measurement receiving switch comprises an input end and at least one output end, the input end of the measurement receiving switch is connected to a measurement output interface arranged on the second rear panel, the measurement output interface is connected to the measurement extension interface, and each output end of the measurement receiving switch is respectively connected to a second directional coupler;

[0045] The control module is arranged in the second chassis and connected to the network port. The control module includes a SCPI parser. The SCPI is a standard command for programmable instruments. The SCPI parser includes a command receiving submodule, a preprocessing submodule, a syntax parsing submodule, a command mapping submodule, a task scheduling submodule, an execution and status management submodule, and a result formatting and response submodule. Figure 4 As shown in the figure, the workflow of these submodules in the SCPI parser includes:

[0046] The command receiving submodule receives the SCPI command string;

[0047] The preprocessing submodule cleans the SCPI command string and splits it;

[0048] The syntax parsing submodule parses the root node, subnode, and parameters of the SCPI command string;

[0049] The command mapping submodule searches and matches the function module according to the split and parsed SCPI command string;

[0050] The task scheduling submodule schedules the matched functional modules and executes commands;

[0051] The execution and status management submodule uses the scheduled function modules to execute tasks and update the status;

[0052] The result formatting and response submodule generates the SCPI response and returns the data.

[0053] The functional modules mentioned above refer to each direct connection control switch, each reference receiving switch, each measurement receiving switch, and each second directional coupler of the port expansion device.

[0054] Preferably, the control module also includes a VXI-11 protocol stack, which is the 11th protocol for the multifunctional modular expansion bus in the instrument field. The VXI-11 protocol stack includes a network communication submodule, a data encapsulation and analysis submodule, a state management and asynchronous notification submodule, and a data return submodule. The network communication submodule is used to implement TCP / IP communication, process the sending and receiving of data packets, and use the RPC (remote procedure call) protocol to process remote calls between the host and the instrument; the data encapsulation and analysis submodule is used to encapsulate SCPI commands in VXI-11 RPC data packets, unpack the received RPC data packets, and hand over the commands therein to the SCPI parser; the state management and asynchronous notification submodule is used to monitor the current task status, support asynchronous errors and completion notifications, and meet the host's status query requirements for the instrument; the data return submodule is used to return the execution results or status information to the host through the VXI-11 protocol. Through the VXI-11 protocol stack, remote control of the port expansion device can be achieved, and the above-mentioned host is a remote computer used to control the port device. More preferably, the device supports VISA (Virtual Instrument Software Architecture) standard and LXI (Local Area Network-based Modular Test Platform) standard, the host software can control the device through the VISA virtual interface, the device supports device connection by entering the IP address through the browser, and viewing device information and operating the device in the browser interface.

[0055] The above configuration of the control module makes the port expansion device have good versatility and can be widely used in various automatic test systems and used in combination with vector network analyzers of various specifications.

[0056] like Figure 3 The figure shows the connection diagram of the vector network analyzer and the port expansion device when n=4. Figure 1 The same as shown in Figure 3In the port expansion device, the number of the direct control switch, the direct input interface, the reference receiving switch, the reference output interface, the measurement receiving switch, and the measurement output interface are all 2. At the same time, m=3, that is, the number of the second port and the second directional coupler are both 3.

[0057] In this example, the total number of available ports is 2+3=5. By analogy, in general, after the vector network analyzer of the present application is connected to the port expansion device, the total number of available ports is n / 2+m.

[0058] Working method:

[0059] When the vector network analyzer is working, the one-to-many switch can switch the excitation source to the first port on the front panel for testing, or to the direct output port on the rear panel. The reference receiver and the measurement receiver can also select the first port or the expansion interface on the rear panel respectively through the one-to-two switch.

[0060] The port extension device can be controlled by the vector network analyzer, or the host, vector network analyzer, and port extension device can be connected in the same local area network to form a vector network analyzer system. The host controls the vector network analyzer and the port extension device respectively through SCPI instructions.

[0061] The above are only some of the embodiments listed in this application and are not intended to limit this application.

Claims

1. A vector network analyzer, characterized in that: include: n / 2 first ports; Motivational source; A one-to-many switch, comprising an input terminal and n output terminals, n≥4, and n is an even number, the input terminal of the one-to-many switch is connected to an excitation source, the n / 2 output terminals are respectively connected to a first directional coupler, and the other n / 2 output terminals are respectively connected to a direct output interface, and each first directional coupler is respectively connected to each first port; n one-to-two switches are divided into two groups, each group has n / 2 switches, the one-to-two switches include an output end and two input ends, one input end of each one-to-two switch in the first group is connected to each first directional coupler, and one input end of each one-to-two switch in the second group is also connected to each first directional coupler; n / 2 reference receivers are respectively connected to the output ends of the one-to-two switches of the first group; n / 2 measurement receivers are respectively connected to the output ends of the one-to-two switches of the second group; n / 2 reference expansion interfaces are respectively connected to the other input end of each one-to-two switch of the first group; The n / 2 measurement expansion interfaces are respectively connected to the other input end of each one-to-two switch of the second group.

2. The vector network analyzer according to claim 1, characterized in that: It also includes a first chassis, in which the excitation source, the one-to-many switch, the one-to-two switch, the reference receiver and the measurement receiver are all arranged.

3. The vector network analyzer according to claim 2, characterized in that: The first chassis includes a first front panel and a first rear panel.

4. The vector network analyzer according to claim 3, characterized in that: The first port is arranged on the first front panel.

5. The vector network analyzer according to claim 3, characterized in that: The direct output interface, reference expansion interface, and measurement expansion interface are all arranged on the first rear panel.

6. A port expansion device, characterized in that: Used to perform port expansion on the vector network analyzer described in any one of claims 1 to 5, comprising: m second ports, m≥n / 2, each second port is connected to a second directional coupler; n / 2 direct-connection control switches, each of which includes an input terminal and at least one output terminal, the input terminal of the direct-connection control switch is connected to a direct-connection input interface, the direct-connection input interface is connected to a direct-connection output interface, and each output terminal of the direct-connection control switch is connected to a second directional coupler; n / 2 reference receiving switches, the reference receiving switches comprising an input end and at least one output end, the input end of the reference receiving switch being connected to a reference output interface provided on the second rear panel, the reference output interface being connected to the reference extension interface, and each output end of the reference receiving switch being connected to a second directional coupler; n / 2 measurement receiving switches, wherein the measurement receiving switches include an input end and at least one output end, the input end of the measurement receiving switch is connected to a measurement output interface provided on the second rear panel, the measurement output interface is connected to the measurement expansion interface, and each output end of the measurement receiving switch is respectively connected to a second directional coupler.

7. The port expansion device according to claim 6, characterized in that: It also includes a second chassis, which includes a second front panel and a second rear panel. The second rear panel is provided with a network port, the second port is provided on the second front panel, and the direct input interface, reference output interface, and measurement output interface are all provided on the second rear panel.

8. The port expansion device according to claim 7, characterized in that: The second directional coupler, the direct connection control switch, the reference receiving switch and the measurement receiving switch are all arranged in the second chassis.

9. The port expansion device according to claim 7, characterized in that: It also includes a control module disposed in the second chassis, the control module is connected to the network port, the control module includes a SCPI parser, and the SCPI parser includes a command receiving submodule, a preprocessing submodule, a syntax parsing submodule, a command mapping submodule, a task scheduling submodule, an execution and status management submodule, and a result formatting and response submodule; The command receiving submodule is used to receive SCPI command strings; The preprocessing submodule is used to clean the SCPI command string and split it; The syntax parsing submodule is used to parse the root node, subnode, and parameters of the SCPI command string; The command mapping submodule is used to search and match the functional modules according to the split and parsed SCPI command character string, and the functional modules are each direct-connect control switch, each reference receiving switch, each measurement receiving switch, and each second directional coupler; The task scheduling submodule is used to schedule the matched functional modules and execute commands; The execution and status management submodule is used to execute tasks and update status using the scheduled function modules; The result formatting and response submodule is used to generate SCPI responses and return data.

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