Terahertz low-noise amplifier noise coefficient testing system and method
By introducing terahertz isolators, terahertz attenuators and additional terahertz low noise amplifiers into the terahertz low noise amplifier test system, the problem of low noise emission noise coefficient testing accuracy in the terahertz band in the terahertz band is solved, effectively testing equipment with large output power is achieved, and testing accuracy and range are improved.
Patent Information
- Application Number
- CN202411614318.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-13
- Publication Date
- 2025-03-07
AI Technical Summary
In the prior art, the test accuracy of the low noise emission noise coefficient in the terahertz band is low, and traditional methods are difficult to effectively test terahertz low noise emission devices with large output power.
A terahertz low-noise amplification noise coefficient test system was designed. By setting up a terahertz isolator and terahertz attenuator between the terahertz low-noise amplification and terahertz downconversion module to be tested, and introducing additional terahertz low-noise amplification, the test was performed using the Y-factor method.
The test accuracy of the terahertz low-noise noise discharge coefficient is improved and the measurement range is broadened, making the system suitable not only for devices with smaller output power, but also for devices with larger output power, reducing the impact of its own noise on the test results.
Smart Images
Figure CN119574997A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of terahertz testing and measurement, and in particular to a terahertz low-noise amplifier noise coefficient testing system and method. Background Art
[0002] Terahertz noise refers to the unexpected random signal in the circuit. Terahertz noise is common in terahertz devices, affecting and interfering with the transmission of normal signals, and even completely drowning out the required signals. It is very harmful to terahertz devices, so it is necessary to accurately test and measure it. The noise factor is usually used to quantitatively indicate the strength of the noise. The noise factor is the ratio of the signal-to-noise ratio at the input and output ends of the device under test. The noise factor reflects the ability of terahertz devices to receive and process tiny signals and is a key indicator of terahertz devices.
[0003] Terahertz low noise amplifiers are mainly used to amplify the power of input signals and improve the signal-to-noise ratio. They are the core components of the front end of transceivers in terahertz mobile communications and navigation systems. The noise factor, as a key parameter of terahertz low noise amplifiers, directly determines the actual performance of terahertz low noise amplifiers. However, there is currently a lack of test methods for the noise factor of low noise amplifiers in the terahertz frequency band. The test accuracy of traditional test methods is relatively low. Traditional methods directly connect the output end of the low noise amplifier to be tested to the down-conversion module. The noise factor of the down-conversion module and other parts is relatively large in the terahertz frequency band, which affects the accuracy of the test results and makes the test error in the terahertz frequency band large. On the other hand, when the output power of the low noise amplifier to be tested is large, it is easy to cause compression saturation at the receiving end, resulting in errors in the noise factor test results.
[0004] Therefore, there is an urgent need to propose a terahertz low-noise amplifier noise coefficient testing system and method. By improving the traditional noise coefficient testing method, the testing accuracy of the low-noise amplifier noise coefficient in the terahertz frequency band can be improved. At the same time, it is suitable for the noise coefficient testing of high-power terahertz low-noise amplifiers. Summary of the invention
[0005] In order to improve the test accuracy of the noise coefficient of a terahertz low-noise amplifier, the present invention proposes a terahertz low-noise amplifier noise coefficient test system and method, which realizes the accurate measurement of the noise coefficient of the terahertz low-noise amplifier, broadens the measurement range of the terahertz low-noise amplifier, and is conducive to the research and development of terahertz related devices and equipment.
[0006] To achieve the above object, the present invention adopts the following technical solution:
[0007] A terahertz low noise amplifier noise coefficient test system comprises a terahertz noise source, a device to be tested, a terahertz isolator, a terahertz attenuator, a terahertz low noise amplifier, a signal source, a terahertz down-conversion module and a signal receiving host. The terahertz noise source, the device to be tested, the terahertz isolator, the terahertz attenuator, the terahertz low noise amplifier, the terahertz down-conversion module and the signal receiving host are connected in sequence, and the signal source is connected to the terahertz down-conversion module.
[0008] Preferably, the terahertz noise source is used to generate a broadband terahertz noise signal; the device to be tested is a terahertz low noise amplifier whose noise coefficient is to be tested; the terahertz isolator is used to reduce the reflection of the terahertz noise signal; the terahertz attenuator is used to attenuate the terahertz noise signal; the terahertz low noise amplifier is used to amplify the power of the terahertz noise signal; the signal source is used to provide a local oscillator signal for a terahertz down-conversion module; the terahertz down-conversion module is used to mix the terahertz noise signal output by the terahertz low noise amplifier with the local oscillator signal provided by the signal source; and the signal receiving host is used to measure the received terahertz noise signal.
[0009] Preferably, the noise coefficient of the device under test is F2 and the gain is G2; the noise coefficient of the terahertz isolator is F3; the noise coefficient of the terahertz attenuator is F4; and the noise coefficient of the terahertz low noise amplifier is F5.
[0010] A method for testing the noise coefficient of a terahertz low-noise amplifier is provided. The terahertz low-noise amplifier noise coefficient testing system as described above is used to perform the test based on the Y-factor method. The test process is as follows:
[0011] A terahertz low noise amplifier (LNA) with a noise coefficient to be tested is selected as the device under test, and a terahertz low noise amplifier noise coefficient test system is built and debugged. The terahertz low noise amplifier noise coefficient test system is used for measurement, and the broadband terahertz noise signal generated by the terahertz noise source is sequentially input into the device under test, the terahertz isolator, the terahertz attenuator, and the terahertz low noise amplifier. After the terahertz isolator reduces the reflection of the terahertz noise signal, the terahertz attenuator attenuates the terahertz noise signal, and the terahertz low noise amplifier performs power amplification on the terahertz noise signal, the terahertz noise signal is input into the terahertz down-conversion module. The signal source is used to provide a local oscillator signal for the terahertz down-conversion module, and the input terahertz noise signal is down-converted in cooperation with the terahertz down-conversion module, and the processed terahertz noise signal is input into the signal receiving host, and the noise coefficient of the device under test is measured using the signal receiving host.
[0012] Preferably, the calculation formula of the noise coefficient of the device under test is:
[0013]
[0014] Where, F2 is the noise coefficient of the device under test; F1 is the total noise coefficient measured by the signal receiving host; G2 is the gain of the device under test; F3 is the noise coefficient of the terahertz isolator; F4 is the noise coefficient of the terahertz attenuator; and F5 is the noise coefficient of the terahertz low noise amplifier.
[0015] Beneficial technical effects brought by the present invention:
[0016] The present invention proposes a terahertz low noise amplifier noise coefficient test system and method, which optimizes the noise coefficient of a traditional terahertz frequency band low noise amplifier, sets a terahertz isolator and a terahertz attenuator between the terahertz low noise amplifier to be tested and the terahertz down-conversion module, and introduces an additional terahertz low noise amplifier to improve the test accuracy of the terahertz low noise amplifier noise coefficient, uses a terahertz isolator to reduce the influence of port signal reflection on the test result of the terahertz low noise amplifier noise coefficient, and uses a terahertz attenuator to avoid receiving end saturation caused by excessive output power of the low noise amplifier to be tested, effectively broadens the measurement range of the terahertz low noise amplifier, so that the present invention is not only suitable for testing terahertz low noise amplifiers with relatively small output power, but also can be used for testing terahertz low noise amplifiers with relatively large output power. At the same time, by introducing an additional terahertz low noise amplifier to improve the sensitivity of the receiving link, the influence of the terahertz down-conversion module and the signal receiving host's own noise on the test result of the terahertz low noise amplifier noise coefficient is reduced.
[0017] The invention proposes a terahertz low-noise amplifier noise coefficient testing system and method, which not only improves the accuracy of the terahertz low-noise amplifier noise coefficient test results, but also broadens the range of terahertz low-noise amplifiers that can be measured by the terahertz low-noise amplifier noise coefficient testing system, thereby achieving accurate acquisition of the terahertz low-noise amplifier noise coefficient and laying a foundation for the research and development of terahertz related devices and equipment. BRIEF DESCRIPTION OF THE DRAWINGS
[0018] Figure 1 The figure is a schematic diagram of a low noise amplifier noise figure test system in the prior art.
[0019] Figure 2 It is a schematic diagram of the noise coefficient testing system of the terahertz low-noise amplifier of the present invention. DETAILED DESCRIPTION
[0020] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments.
[0021] The low noise amplifier noise figure test system used in the prior art is as follows: Figure 1As shown, it includes a terahertz noise source, a device under test (DUT), a signal source, a terahertz down-conversion module and a signal receiving host, wherein the output end of the terahertz noise source is connected to the input end of the device under test, the output end of the device under test is directly connected to the input end of the terahertz down-conversion module, the input end of the terahertz down-conversion module is also connected to the signal source, the signal source is used to provide a local oscillator signal for the terahertz down-conversion module, the output end of the terahertz down-conversion module is connected to the input end of the broadband signal receiving host, and the noise information is read by the broadband signal receiving host for testing. However, on the one hand, due to the relatively large influence of the signal receiving link noise in the terahertz frequency band, the sensitivity of the receiving link is reduced, resulting in a decrease in the test accuracy of the terahertz noise coefficient; on the other hand, when the output power of the device under test is large, it may cause compression saturation of the receiving end, resulting in errors in the test results of the low-noise amplifier noise coefficient, so the actual test of the low-noise amplifier noise coefficient will impose certain restrictions on the power of the device under test.
[0022] In order to solve the problem of low test accuracy of the terahertz low-noise amplifier noise coefficient test system and method used in the prior art, this embodiment proposes a terahertz low-noise amplifier noise coefficient test system, such as Figure 2 As shown, it includes a terahertz noise source, a device to be tested, a terahertz isolator, a terahertz attenuator, a terahertz low noise amplifier, a signal source, a terahertz down-conversion module and a signal receiving host. The terahertz noise source, the device to be tested, the terahertz isolator, the terahertz attenuator, the terahertz low noise amplifier, the terahertz down-conversion module and the signal receiving host are connected in sequence, and the signal source is connected to the terahertz down-conversion module.
[0023] Among them, the terahertz noise source is used to generate a broadband terahertz noise signal; the device to be tested is a terahertz low noise amplifier whose noise coefficient is to be tested; the terahertz isolator is used to reduce the reflection of the terahertz noise signal; the terahertz attenuator is used to attenuate the terahertz noise signal; the terahertz low noise amplifier is used to amplify the power of the terahertz noise signal; the signal source is used to provide a local oscillator signal for the terahertz down-conversion module; the terahertz down-conversion module is used to mix the terahertz noise signal output by the terahertz low noise amplifier with the local oscillator signal provided by the signal source; and the signal receiving host is used to measure the received terahertz noise signal.
[0024] In this embodiment, the noise coefficient of the device under test is F2 and the gain is G2; the noise coefficient of the terahertz isolator is F3; the noise coefficient of the terahertz attenuator is F4; and the noise coefficient of the terahertz low noise amplifier is F5.
[0025] In order to improve the test accuracy of the noise coefficient of the terahertz low-noise amplifier, a method for testing the noise coefficient of the terahertz low-noise amplifier is also proposed in this embodiment. The terahertz low-noise amplifier noise coefficient test system as described above is used to perform the test based on the basic principle of the Y-factor method. The test process is as follows:
[0026] A terahertz low noise amplifier (LNA) with a noise coefficient to be tested is selected as the device under test, and a noise coefficient test system for the terahertz low noise amplifier (LNA) is built and debugged. The output end of the terahertz noise source is connected to the input end of the device under test, the output end of the device under test is connected to the input end of the terahertz isolator, the output end of the terahertz isolator is connected to the input end of the terahertz attenuator, the output end of the terahertz attenuator is connected to the input end of the terahertz low noise amplifier, the output end of the terahertz low noise amplifier is connected to the input end of the terahertz down-conversion module, the input end of the terahertz down-conversion module is also connected to the signal source, the output end of the terahertz down-conversion module is connected to the input end of a signal receiving host, and the output end of the signal receiving host measures and outputs the total noise coefficient in real time.
[0027] When using the terahertz low noise amplifier noise coefficient test system for measurement, the broadband terahertz noise signal generated by the terahertz noise source is sequentially input into the device under test, the terahertz isolator, the terahertz attenuator, and the terahertz low noise amplifier. After the terahertz isolator reduces the reflection of the terahertz noise signal, the terahertz attenuator attenuates the terahertz noise signal, and the terahertz low noise amplifier amplifies the power of the terahertz noise signal, it is input into the terahertz down-conversion module. The signal source is used to provide the local oscillator signal for the terahertz down-conversion module, and the terahertz down-conversion module is used in conjunction with the terahertz down-conversion module. The module performs down-conversion processing on the input terahertz noise signal, and inputs the processed terahertz noise signal into the signal receiving host. The signal receiving host is used to measure the total noise coefficient, and the noise coefficient of the device under test is calculated using formula (1). During the calculation process, the noise coefficient F2 of the device under test is the measured value. The gain G2 of the device under test, the noise coefficient F3 of the terahertz isolator, the noise coefficient F4 of the terahertz attenuator, and the noise coefficient F5 of the terahertz low noise amplifier are all known values. The noise coefficient of the device under test is calculated as:
[0028]
[0029] Where, F2 is the noise coefficient of the device under test; F1 is the total noise coefficient measured by the signal receiving host; G2 is the gain of the device under test; F3 is the noise coefficient of the terahertz isolator; F4 is the noise coefficient of the terahertz attenuator; and F5 is the noise coefficient of the terahertz low noise amplifier.
[0030] In summary, the terahertz low noise amplifier noise coefficient test system and method proposed in the present invention, by setting a terahertz isolator, a terahertz attenuator and an additional terahertz low noise amplifier between the terahertz low noise amplifier to be tested and the terahertz down-conversion module, using the terahertz isolator to reduce the influence of the terahertz noise signal reflection at the output port of the terahertz low noise amplifier to be tested, avoiding the influence of the terahertz noise signal reflection on the test result, and using the terahertz attenuator to prevent the saturation of the receiving end caused by the excessive output power of the low noise amplifier to be tested, so that the terahertz low noise amplifier with a large output power can also be tested with the help of the terahertz low noise amplifier noise coefficient test system and method proposed in the present invention, expanding the range of the terahertz low noise amplifier that can be measured by the terahertz low noise amplifier noise coefficient test system. At the same time, the present invention also improves the sensitivity of the signal receiving link by introducing an additional terahertz low noise amplifier, reduces the influence of the terahertz down-conversion module and the signal receiving host's own noise on the test result of the terahertz low noise amplifier noise coefficient, and effectively improves the test accuracy of the terahertz low noise amplifier noise coefficient.
[0031] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", "connect", and "fix" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood by specific circumstances.
[0032] Of course, the above description is not a limitation of the present invention, and the present invention is not limited to the above examples. Changes, modifications, additions or substitutions made by technicians in this technical field within the essential scope of the present invention should also fall within the protection scope of the present invention.
Claims
1. A terahertz low-noise amplifier noise coefficient test system, characterized in that: The device comprises a terahertz noise source, a device to be tested, a terahertz isolator, a terahertz attenuator, a terahertz low noise amplifier, a signal source, a terahertz down-conversion module and a signal receiving host. The terahertz noise source, the device to be tested, the terahertz isolator, the terahertz attenuator, the terahertz low noise amplifier, the terahertz down-conversion module and the signal receiving host are connected in sequence, and the signal source is connected to the terahertz down-conversion module.
2. The terahertz low noise amplifier noise coefficient test system according to claim 1, characterized in that: The terahertz noise source is used to generate a broadband terahertz noise signal; the device to be tested is a terahertz low noise amplifier whose noise coefficient is to be tested; the terahertz isolator is used to reduce the reflection of the terahertz noise signal; the terahertz attenuator is used to attenuate the terahertz noise signal; the terahertz low noise amplifier is used to amplify the power of the terahertz noise signal; the signal source is used to provide a local oscillator signal for the terahertz down-conversion module; the terahertz down-conversion module is used to mix the terahertz noise signal output by the terahertz low noise amplifier with the local oscillator signal provided by the signal source; and the signal receiving host is used to measure the received terahertz noise signal.
3. The terahertz low noise amplifier noise coefficient test system according to claim 2, characterized in that: The noise coefficient of the device under test is F2 and the gain is G2; the noise coefficient of the terahertz isolator is F3; the noise coefficient of the terahertz attenuator is F4; and the noise coefficient of the terahertz low noise amplifier is F5.
4. A method for testing the noise coefficient of a terahertz low-noise amplifier, characterized in that: The terahertz low-noise amplifier noise coefficient test system as described in claim 3 is used to perform the test based on the Y-factor method. The test process is as follows: A terahertz low noise amplifier (LNA) with a noise coefficient to be tested is selected as the device under test, and a terahertz low noise amplifier noise coefficient test system is built and debugged. The terahertz low noise amplifier noise coefficient test system is used for measurement, and the broadband terahertz noise signal generated by the terahertz noise source is sequentially input into the device under test, the terahertz isolator, the terahertz attenuator, and the terahertz low noise amplifier. After the terahertz isolator reduces the reflection of the terahertz noise signal, the terahertz attenuator attenuates the terahertz noise signal, and the terahertz low noise amplifier performs power amplification on the terahertz noise signal, the terahertz noise signal is input into the terahertz down-conversion module. The signal source is used to provide a local oscillator signal for the terahertz down-conversion module, and the input terahertz noise signal is down-converted in cooperation with the terahertz down-conversion module, and the processed terahertz noise signal is input into the signal receiving host, and the noise coefficient of the device under test is measured using the signal receiving host.
5. The method for testing the noise coefficient of a terahertz low noise amplifier according to claim 4, characterized in that: The calculation formula of the noise coefficient of the device under test is: Where, F2 is the noise coefficient of the device under test; F1 is the total noise coefficient measured by the signal receiving host; G2 is the gain of the device under test; F3 is the noise coefficient of the terahertz isolator; F4 is the noise coefficient of the terahertz attenuator; and F5 is the noise coefficient of the terahertz low noise amplifier.