Automatic test device and method for frequency mixer

Abstract

The invention relates to a mixer automatic test device and method, the mixer automatic test device is composed of a verification mother board, a verification daughter board, a direct current power supply, a radio frequency signal source 1, a radio frequency signal source 2, a frequency spectrograph, a simulation load and an upper computer, and the upper computer is provided with mixer automatic test device upper computer software. And a required input signal, a local oscillator signal, an output load and an external control signal are provided for the frequency mixer, so that the normal work of the frequency mixer is realized. Switching of test items is realized by adjusting the input signal, the local oscillator signal and the control signal. And the function and performance test of the mixer is realized through the test interface. Test indexes comprise frequency conversion loss, radio frequency-intermediate frequency isolation, local oscillator-radio frequency isolation, local oscillator-intermediate frequency isolation and the like. According to the invention, multi-parameter automatic testing of the mixer and the mixer installed on the circuit board card is realized, the working efficiency is improved, and the parameter testing accuracy of an actual application state is improved.

Description

Technical Field

[0001] The present invention relates to a method and a testing device for automatically testing the functions, performances and applicability of a mixer and an application circuit board card composed thereof, belonging to the field of electronic component testing, and particularly to a method for automatically testing the parameters of a domestic mixer. Background Art

[0002] With the increasing progress of various technologies such as electronics and communication, people have put forward higher requirements for the performance of mixers. Due to the advantages of convenient use and low price, mixers have been widely used. However, indicators such as conversion loss and isolation of mixers are crucial for practical applications. Therefore, various relevant tests need to be carried out on mixers to ensure their integrity.

[0003] Currently, the testing of mixers is mostly single-item testing, with low efficiency. After the mixer is installed on the circuit board card, it is generally directly used, and performance testing is rarely carried out. Affected by the electrical characteristics of peripheral electronic components, the performance of the mixer installed on the circuit board card is partially different from that of the single-chip mixer. In applications with high requirements, it is necessary to carry out relevant tests on the mixer installed on the circuit board card. Summary of the Invention

[0004] In view of this, the present invention proposes a method and a testing device for automatically testing a domestic mixer. The basic concept of the present invention is: to provide the required input signal, local oscillator signal, output load and external control signal for the mixer to realize the normal operation of the mixer. By adjusting the input signal, local oscillator signal and control signal, the switching of test items is realized. The functions and performances of the mixer are tested through the test interface. The test indicators include conversion loss, RF-IF isolation, LO-RF isolation and LO-IF isolation, etc.

[0005] The specific technical solutions are as follows:

[0006] An automatic testing device for a mixer includes a verification motherboard, a verification daughter board, an analog load, a host computer and test instruments; the verification motherboard is used to provide interfaces with the verification daughter board, the analog load, the host computer and the test instruments; the verification daughter board is used to install the mixer under test and the application circuit; the analog load is used to provide an output load for the mixer to prevent the mixer from being burned; the test instruments include a DC power supply, a RF signal source and a spectrum analyzer, and the RF signal source provides the required input signal and local oscillator signal for the mixer; the host computer provides a control signal.

[0007] Further, different types of mixers are equipped with different verification daughter boards. There is a unified and compatible test interface between the verification daughter board and the verification mother board. The verification mother board includes a switch matrix, a power supply interface, an isolation attenuator 1, and an isolation attenuator 2. The host computer is installed with the mixer automatic test device host computer software, and the RF signal source includes RF signal source 1 and RF signal source 2.

[0008] A mixer automatic test method realizes the switching of test items by adjusting the input signal, the local oscillator signal, and the control signal; realizes the function and performance test of the mixer through the interface provided by the verification mother board; the test indicators include conversion loss, local oscillator-RF isolation, local oscillator-IF isolation, and RF-IF isolation.

[0009] Further, the conversion loss test is specifically as follows: RF signal source 1 is connected to isolation attenuator 1, and isolation attenuator 1 is connected to the RF interface of the mixer through the switch matrix; RF signal source 2 is connected to isolation attenuator 2, and isolation attenuator 2 is connected to the local oscillator interface of the mixer through the switch matrix; the IF interface of the mixer is connected to interface 3 through the switch matrix; interface 3 is connected to the spectrum analyzer; the signal switching of the switch matrix is controlled by the host computer; the host computer controls RF signal source 1 and RF signal source 2 to output RF signals with specific frequencies and amplitudes respectively; the host computer controls the spectrum analyzer to receive the signals and transmit them to the host computer control software; the host computer control software calculates the difference between the data output by RF signal source 1 and the spectrum analyzer, and after compensating for the attenuation value of the isolation attenuator, the conversion loss index of the mixer can be obtained.

[0010] Further, the local oscillator-RF isolation test is specifically as follows: RF signal source 2 is connected to isolation attenuator 2, and isolation attenuator 2 is connected to the local oscillator interface of the mixer through the switch matrix; the RF interface of the mixer is connected to interface 3 through the switch matrix; interface 3 is connected to the spectrum analyzer; the IF interface of the mixer is connected to the analog load through the switch matrix; the signal switching of the switch matrix is controlled by the host computer; the host computer controls RF signal source 2 to output RF signals with specific frequencies and amplitudes; the host computer controls the spectrum analyzer to receive the signals and transmit them to the host computer control software; the host computer control software calculates the difference between the data output by RF signal source 2 and the spectrum analyzer, and after compensating for the attenuation value of the isolation attenuator, the local oscillator-RF isolation index of the mixer can be obtained.

[0011] Further, the local oscillator - intermediate frequency isolation test is specifically as follows: The RF signal source 2 is connected to the isolation attenuator 2, and the isolation attenuator 2 is connected to the local oscillator interface of the mixer through the switch matrix; the intermediate frequency interface of the mixer is connected to the interface 3 through the switch matrix; the interface 3 is connected to the spectrum analyzer; the RF interface of the mixer is connected to the analog load through the switch matrix; the signal switching of the switch matrix is controlled by the host computer; the host computer controls the RF signal source 2 to output an RF signal with a specific frequency and amplitude; the host computer controls the spectrum analyzer to receive the signal and transmit it to the host computer control software; the host computer control software can calculate the local oscillator - intermediate frequency isolation test index of the mixer by the difference between the data output by the RF signal source 2 and the spectrum analyzer and compensating for the attenuation value of the isolation attenuator.

[0012] Further, the RF - intermediate frequency isolation test is specifically as follows: The RF signal source 1 is connected to the isolation attenuator 1, and the isolation attenuator 1 is connected to the RF interface of the mixer through the switch matrix; the intermediate frequency interface of the mixer is connected to the interface 3 through the switch matrix; the interface 3 is connected to the spectrum analyzer; the local oscillator interface of the mixer is connected to the analog load through the switch matrix; the signal switching of the switch matrix is controlled by the host computer; the host computer controls the RF signal source 1 to output an RF signal with a specific frequency and amplitude; the host computer controls the spectrum analyzer to receive the signal and transmit it to the host computer control software; the host computer control software can calculate the RF - intermediate frequency isolation test index of the mixer by the difference between the data output by the RF signal source 1 and the spectrum analyzer and compensating for the attenuation value of the isolation attenuator.

[0013] Further, the host computer software includes a detection and control module, a data display module, a storage and printing module, a self - test and calibration module, a fault location module, and a data management module.

[0014] Beneficial Effects

[0015] 1. The present invention realizes the multi - parameter automatic test of the mixer and the mixer installed on the circuit board card, improving the work efficiency.

[0016] 2. The present invention improves the test accuracy of the parameters of the mixer in the actual application state.

[0017] 3. The present invention ensures the performance of the mixer in applications with high requirements.

[0018] 4. The present invention mainly tests and verifies the performance indicators of related domestic devices and circuit board cards, and better replaces imported devices. Description of the Drawings

[0019] Figure 1 Schematic Diagram of the Composition of the Mixer Automatic Test Device

[0020] Figure 2 Schematic Diagram of the Composition of the Host Computer Software of the Mixer Automatic Test Device

[0021] Figure 3 、Schematic Diagram of the Operation Process of the Host Computer Software for the Automatic Test Device of the Mixer Specific Embodiments

[0022] The automatic test device of the mixer of the present invention mainly consists of eight parts: a verification motherboard, a verification daughter board, a DC power supply, a radio frequency signal source 1, a radio frequency signal source 2, a spectrum analyzer, an analog load, and a host computer (including control software), as Figure 1 shown.

[0023] Test instruments such as the DC power supply, the radio frequency signal source 1, the radio frequency signal source 2, and the spectrum analyzer are uniformly controlled by the host computer software of the automatic test device of the mixer. The verification motherboard mainly realizes functions such as the interfaces of the test instruments, the host computer, and the verification daughter board. The analog load is connected to the corresponding interface of the mixer when necessary to prevent the mixer from being burned. The mixer under test and the application circuit are installed on the verification daughter board, and each interface, switch matrix, etc. are installed on the verification motherboard. Different types of mixers can be equipped with different verification daughter boards, and there are unified and compatible test interfaces between the verification daughter board and the verification motherboard. The host computer is installed with the host computer software of the automatic test device of the mixer.

[0024] The host computer software can meet the monitoring requirements of real-time status data during the verification process, and at the same time support flexible control instruction execution operations and the use requirements of historical data query, enabling users to have a better interaction experience during use. The software adopts a componentized and generalized software hierarchical modular design, dividing the software into multiple processing unit layers.

[0025] Application Presentation Layer: The application presentation layer is the main interaction interface between the host computer software and the operator, providing real-time monitoring of status data, instruction control operations on the test system, query and retrieval of historical test data, and interactive editing of test scripts. In addition to conventional curves and tables, this layer also provides components such as dials, knobs, and switches to improve the operability of the software.

[0026] Data Processing Layer: The data processing layer is responsible for collecting the status data of the test system, parsing the status data according to the interface control file, saving the collected status data in the form of a text database, and sending the control operations selected by the user to the test system in the form of an instruction sequence. In addition, the data processing layer also provides a query interface to support users' query of historical test data.

[0027] Data Management Layer: Provides various test templates in the form of database tables or file sets, and receives the real-time status data from the data processing layer and stores it in the corresponding database and file set to form test data products, supporting operators to retrieve and query the test data after the test.

[0028] The host computer software is mainly divided into a detection and control module, a data display module, a storage and printing module, a self-checking and calibration module, a fault location module, a data management module, etc., as Figure 2 shown.

[0029] The specific tests that can be carried out by the present invention are as follows:

[0030] Frequency conversion loss test. The RF signal source 1 is connected to the isolation attenuator 1, and the isolation attenuator 1 is connected to the RF interface of the mixer through the switch matrix. The RF signal source 2 is connected to the isolation attenuator 2, and the isolation attenuator 2 is connected to the local oscillator interface of the mixer through the switch matrix. The intermediate frequency interface of the mixer is connected to the interface 3 through the switch matrix. The interface 3 is connected to the spectrum analyzer. The signal switching of the switch matrix is realized by the control of the host computer. The host computer controls the RF signal source 1 and the RF signal source 2 to output RF signals with specific frequencies and amplitudes respectively. The host computer controls the spectrum analyzer to receive the signals and transmit them to the host computer control software. After the host computer control software calculates the difference between the data output by the RF signal source 1 and the spectrum analyzer and compensates for the attenuation value of the isolation attenuator, the frequency conversion loss index of the mixer can be obtained.

[0031] Local oscillator-RF isolation test. The RF signal source 2 is connected to the isolation attenuator 2, and the isolation attenuator 2 is connected to the local oscillator interface of the mixer through the switch matrix. The RF interface of the mixer is connected to the interface 3 through the switch matrix. The interface 3 is connected to the spectrum analyzer. When necessary, the intermediate frequency interface of the mixer is connected to the analog load through the switch matrix. The signal switching of the switch matrix is realized by the control of the host computer. The host computer controls the RF signal source 2 to output RF signals with specific frequencies and amplitudes. The host computer controls the spectrum analyzer to receive the signals and transmit them to the host computer control software. After the host computer control software calculates the difference between the data output by the RF signal source 2 and the spectrum analyzer and compensates for the attenuation value of the isolation attenuator, the local oscillator-RF isolation index of the mixer can be obtained.

[0032] Local oscillator-intermediate frequency isolation test. The RF signal source 2 is connected to the isolation attenuator 2, and the isolation attenuator 2 is connected to the local oscillator interface of the mixer through the switch matrix. The intermediate frequency interface of the mixer is connected to the interface 3 through the switch matrix. The interface 3 is connected to the spectrum analyzer. When necessary, the RF interface of the mixer is connected to the analog load through the switch matrix. The signal switching of the switch matrix is realized by the control of the host computer. The host computer controls the RF signal source 2 to output RF signals with specific frequencies and amplitudes. The host computer controls the spectrum analyzer to receive the signals and transmit them to the host computer control software. After the host computer control software calculates the difference between the data output by the RF signal source 2 and the spectrum analyzer and compensates for the attenuation value of the isolation attenuator, the local oscillator-intermediate frequency isolation test index of the mixer can be obtained.

[0033] RF-IF isolation test. The RF signal source 1 is connected to the isolation attenuator 1. The isolation attenuator 1 is connected to the RF interface of the mixer through the switch matrix. The IF interface of the mixer is connected to interface 3 through the switch matrix. Interface 3 is connected to the spectrum analyzer. When necessary, the LO interface of the mixer is connected to the analog load through the switch matrix. The signal switching of the switch matrix is controlled by the host computer. The host computer controls the RF signal source 1 to output an RF signal with a specific frequency and amplitude. The host computer controls the spectrum analyzer to receive the signal and transmit it to the host computer control software. After the host computer control software calculates the difference between the data output by the RF signal source 1 and the spectrum analyzer and compensates for the attenuation value of the isolation attenuator, the RF-IF isolation test index of the mixer can be obtained.

[0034] The main operation process is as Figure 3 shown, and the specific implementation method is described as follows:

[0035] 1. Set up the test environment: Prepare the test object, connect the cables of the chassis and instruments, etc.

[0036] 2. Set the hardware configuration: Set the hardware environment before the test, select the hardware used in the test in the system and set the relevant parameters.

[0037] 3. Edit the test program: Edit the test program according to the test process, including the test method, the calculation formula of the test data, and the settings of each external device.

[0038] 4. Perform the initialization test: Based on the existing built platform, conduct the first test verification. If the verification fails, check whether the test device is built correctly.

[0039] 5. Perform the test: Conduct various tests according to the set conditions.

[0040] 6. Judge the result: If the test result is unqualified, check the test device. After troubleshooting, retest.

[0041] 7. Report output: Support multiple document formats such as *.xls, *.doc, *.txt, etc.

Claims

1. A mixer automatic test device, characterized in that: It includes a verification motherboard, a verification daughterboard, a simulated load, a host computer and a test instrument; the verification motherboard is used to provide an interface with the verification daughterboard, the simulated load, the host computer and the test instrument; the verification daughterboard is used to install the mixer to be tested and the application circuit; the simulated load is used to provide an output load for the mixer to prevent the mixer from being burned; the test instrument includes a DC power supply, a radio frequency signal source and a spectrum analyzer, the radio frequency signal source provides the mixer with the required input signal and local oscillator signal; the host computer provides a control signal.

2. The automatic mixer test device according to claim 1, characterized in that: Different types of mixers are equipped with different verification daughter boards. The verification daughter boards and the verification mother board have a unified and compatible test interface. The verification mother board includes a switch matrix, a power supply interface, an isolation attenuator 1, an isolation attenuator 2, and the host computer is installed with the host computer software of the mixer automatic test device. The RF signal source includes RF signal source 1 and RF signal source 2.

3. A mixer automatic testing method, based on the testing device according to any one of claims 1 to 2, characterized in that: The test items are switched by adjusting the input signal, local oscillator signal and control signal. The function and performance test of the mixer is realized by verifying the interface provided by the motherboard. The test indicators include frequency conversion loss, local oscillator-RF isolation, local oscillator-IF isolation and RF-IF isolation.

4. A mixer automatic testing method according to claim 3, characterized in that: The conversion loss test is specifically as follows: the RF signal source 1 is connected to the isolation attenuator 1, and the isolation attenuator 1 is connected to the RF interface of the mixer through the switch matrix; The radio frequency signal source 2 is connected to the isolation attenuator 2, and the isolation attenuator 2 is connected to the local oscillator interface of the mixer through the switch matrix; the intermediate frequency interface of the mixer is connected to the interface 3 through the switch matrix; Interface 3 is connected to the spectrum analyzer; the signal switching of the switch matrix is ​​realized by the host computer control; the host computer controls the RF signal source 1 and the RF signal source 2 to output RF signals of specific frequency and amplitude respectively; the host computer controls the spectrum analyzer to receive the signal and transmit it to the host computer control software; The host computer control software can calculate the frequency conversion loss index of the mixer by taking the difference between the data output by the RF signal source 1 and the spectrum analyzer and compensating the attenuation value of the isolation attenuator.

5. The method for automatically testing a mixer according to claim 3, characterized in that: The local oscillator-RF isolation test is specifically as follows: the RF signal source 2 is connected to the isolation attenuator 2, and the isolation attenuator 2 is connected to the local oscillator interface of the mixer through the switch matrix; the RF interface of the mixer is connected to the interface 3 through the switch matrix; the interface 3 is connected to the spectrum analyzer; the intermediate frequency interface of the mixer is connected to the simulated load through the switch matrix; the signal switching of the switch matrix is ​​controlled by the host computer; the host computer controls the RF signal source 2 to output an RF signal of a specific frequency and amplitude; the host computer controls the spectrum analyzer to receive the signal and transmit it to the host computer control software; the host computer control software calculates the local oscillator-RF isolation index of the mixer by the difference between the data output by the RF signal source 2 and the spectrum analyzer, and compensates for the attenuation value of the isolation attenuator.

6. A mixer automatic testing method according to claim 3, characterized in that: The local oscillator-intermediate frequency isolation test is specifically as follows: the RF signal source 2 is connected to the isolation attenuator 2, and the isolation attenuator 2 is connected to the local oscillator interface of the mixer through the switch matrix; the intermediate frequency interface of the mixer is connected to the interface 3 through the switch matrix; the interface 3 is connected to the spectrum analyzer; the RF interface of the mixer is connected to the simulated load through the switch matrix; the signal switching of the switch matrix is ​​realized by the host computer control; the host computer controls the RF signal source 2 to output an RF signal of a specific frequency and amplitude; the host computer controls the spectrum analyzer to receive the signal and transmit it to the host computer control software; the host computer control software calculates the local oscillator-intermediate frequency isolation test index of the mixer by the difference between the data output by the RF signal source 2 and the spectrum analyzer, and compensates for the attenuation value of the isolation attenuator.

7. A mixer automatic testing method according to claim 3, characterized in that: The RF-IF isolation test is specifically as follows: RF signal source 1 is connected to isolation attenuator 1, and isolation attenuator 1 is connected to the RF interface of the mixer through a switch matrix; the IF interface of the mixer is connected to interface 3 through a switch matrix; interface 3 is connected to a spectrum analyzer; the local oscillator interface of the mixer is connected to an analog load through a switch matrix; the signal switching of the switch matrix is ​​controlled by a host computer; the host computer controls the RF signal source 1 to output an RF signal of a specific frequency and amplitude; the host computer controls the spectrum analyzer to receive the signal and transmit it to the host computer control software; the host computer control software calculates the RF-IF isolation test index of the mixer by taking the difference between the data output by the RF signal source 1 and the spectrum analyzer and compensating for the attenuation value of the isolation attenuator.

8. A mixer automatic testing method according to any one of claims 3 to 7, characterized in that: The upper computer software includes detection control module, data display module, storage and printing module, self-test and verification module, fault location module and data management module.

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