Low-noise amplifier chip noise coefficient test receiving front end and test system

Abstract

The invention discloses a low-noise amplifier chip noise coefficient test receiving front end and a low-noise amplifier chip noise coefficient test system. The receiving front end comprises an antenna for receiving the radiation power of the terahertz cold and heat source and transmitting the radiation power to the to-be-tested piece; the terahertz low-noise amplifier is used for carrying out low-noise amplification processing on a signal output by the to-be-tested piece and transmitting the signal to the terahertz frequency mixing module; the signal source frequency doubling component provides a local oscillator signal and mixes the local oscillator signal with the amplified terahertz noise signal; the terahertz frequency mixing module is used for converting the terahertz noise signal into an intermediate frequency signal; the intermediate frequency amplification module is used for carrying out amplification processing on the intermediate frequency signal after frequency conversion; the intermediate-frequency filtering module is used for filtering clutters and interference signals in the intermediate-frequency signals; and the frequency spectrograph is used for detecting the filtered intermediate-frequency signal and displaying the intermediate-frequency output power. The test system comprises a receiving front end, and further comprises a test output module for calculating and obtaining the noise coefficient of the to-be-tested piece based on the intermediate frequency output power data. According to the invention, through innovatively receiving the combination of the front-end design and the cold and heat source test scheme, a significant breakthrough is realized in three core dimensions of cost control, applicability expansion and test precision guarantee.

Description

Technical Field

[0001] This invention belongs to the field of semiconductor device testing technology, and in particular to a low-noise amplifier chip noise figure testing receiver front-end and testing system. Background Technology

[0002] In the development of terahertz low-noise amplifier chips, performance characterization is a core step, and the noise figure (NF) is a key indicator for measuring chip performance. The noise figure directly reflects the degree of noise introduced by the low-noise amplifier during signal amplification; the lower the value, the higher the fidelity of the amplifier to the useful signal, and the more significant the improvement in the sensitivity of the receiving system. Therefore, accurately obtaining noise figure data is an important prerequisite for evaluating the rationality of chip design, optimizing chip performance, and ensuring the reliable operation of subsequent systems. Currently, testing methods for the noise figure of low-noise amplifiers exhibit significant frequency band dependence and face significant technical bottlenecks at high frequencies. In the low-frequency band (usually below 50 GHz), testing techniques are relatively mature, and noise figure testing can generally be completed by using a noise meter in conjunction with a noise source. This method is simple to operate, has high testing accuracy, and can meet the testing needs of low-frequency chips. When the frequency increases above 50 GHz, frequency extension at the noise source is required. Solid-state noise sources have limited testing frequencies and are expensive; therefore, for terahertz testing, a hot / cold source method can be used to conduct the corresponding noise figure test. Summary of the Invention

[0003] The purpose of this invention is to address the problems of a lack of suitable solid-state noise sources or the excessively high cost of existing solid-state noise sources in the terahertz band. By optimizing the cold and hot source test architecture, it provides a low-cost and easily implemented solution. This invention addresses the characteristics of high signal attenuation and complex noise characteristics in the terahertz band by designing a receiver front-end structure adapted to this band, ensuring the accuracy and stability of noise figure testing.

[0004] The technical solution to achieve the objective of this invention is as follows: On one hand, a low-noise amplifier chip noise figure test receiving front-end is provided. The receiving front-end includes an antenna, a device under test (DUT), a terahertz low-noise amplifier, a terahertz mixer module, a signal source frequency multiplier component, an intermediate frequency (IF) amplifier module, an IF filter module, and a spectrum analyzer. The output terminal of the antenna is connected to the input terminal of the DUT, the output terminal of the DUT is connected to the input terminal of the terahertz low-noise amplifier, the output terminal of the terahertz low-noise amplifier is connected to the RF input terminal of the terahertz mixer module, the output terminal of the signal source frequency multiplier component is connected to the local oscillator input terminal of the terahertz mixer module, the output terminal of the terahertz mixer module is connected to the input terminal of the IF amplifier module, the output terminal of the IF amplifier module is connected to the input terminal of the IF filter module, and the output terminal of the IF filter module is connected to the input terminal of the spectrum analyzer.

[0005] The antenna is used to receive terahertz hot and cold source radiation power and transmit the received radiation power signal to the device under test.

[0006] The terahertz low-noise amplifier is used to amplify the signal output by the device under test in a low-noise manner and transmit it to the terahertz mixer module.

[0007] The signal source frequency multiplier component is used to provide a local oscillator signal that meets the frequency requirements and transmit it to the terahertz mixing module to mix with the terahertz noise signal after being amplified by the terahertz low-noise amplifier.

[0008] The terahertz mixer module is used to convert terahertz noise signals into intermediate frequency signals.

[0009] The intermediate frequency amplification module is used to amplify the intermediate frequency signal after frequency conversion;

[0010] The intermediate frequency filtering module is used to filter out noise and interference signals in the amplified intermediate frequency signal;

[0011] The spectrum analyzer is used to detect the filtered intermediate frequency signal and display the intermediate frequency output power.

[0012] Furthermore, the receiving front end adopts a double-sideband receiving method.

[0013] Furthermore, the frequency of the local oscillator signal is matched with the frequency of the terahertz noise signal.

[0014] Furthermore, the signal source frequency multiplier component includes:

[0015] The signal source is used to output a basic signal and transmit it to the frequency multiplier;

[0016] The frequency multiplier is used to multiply the frequency of the basic signal, generate a local oscillator signal, and transmit it to the terahertz mixer module to mix with the terahertz noise signal after being amplified by the terahertz low-noise amplifier.

[0017] The output of the signal source is connected to the input of the frequency multiplier, and the output of the frequency multiplier is connected to the local oscillator input of the terahertz mixer module.

[0018] Furthermore, the antenna is a terahertz band-specific corrugated antenna, and the operating frequency band of the corrugated antenna is consistent with the frequency band of the terahertz cold and hot source radiation power.

[0019] Furthermore, the filtering frequency band of the intermediate frequency filtering module is 100MHz-500MHz.

[0020] Furthermore, the spectrum analyzer is a power detection device with an accuracy of not less than 0.02dB, used to achieve high-precision acquisition of intermediate frequency output power.

[0021] Furthermore, the output power of the intermediate frequency amplifier module is greater than 0 dBm.

[0022] Furthermore, the terahertz low-noise amplifier needs to control its own noise introduction during the low-noise amplification process.

[0023] On the other hand, a low-noise amplifier chip noise figure testing system is provided, the system including the receiving front end, and further including:

[0024] The test output module is used to calculate and obtain the noise figure of the device under test based on the intermediate frequency output power data.

[0025] Compared with existing technologies, the significant advantages of this invention are as follows: Compared with existing terahertz low-noise amplifier chip noise figure testing technologies, this invention achieves significant breakthroughs in three core dimensions—cost control, applicability expansion, and test accuracy assurance—through an innovative combination of receiver front-end design and hot / cold source testing schemes. Specifically, these include:

[0026] I. Significantly reduce testing costs and solve the problem of dependence on solid-state noise sources.

[0027] Addressing the industry pain point of scarce and high-cost solid-state noise sources in the terahertz band (existing terahertz solid-state noise sources typically cost over one million yuan per unit and require separate procurement for different frequency bands), this invention adopts a "cold / hot source + receiving front-end" test architecture, completely eliminating reliance on traditional solid-state noise sources. There is no need to invest in purchasing multi-band dedicated solid-state noise sources; simply using a low-cost liquid nitrogen cold load (reusable) combined with a high-temperature heat load can meet the testing requirements of low-noise amplifier chips across the entire terahertz band (0.3THz~10THz). The cost of setting up a single test system is low, making it suitable for small and medium-sized R&D teams and cost control requirements in mass production scenarios.

[0028] II. Precise control of the signal link to ensure high testing accuracy

[0029] This invention improves test accuracy directly at the hardware level by optimizing the intermediate frequency link design of the receiving front end.

[0030] 1. The front end is set up with a signal processing link of "terahertz low noise pre-amplification + intermediate frequency filtering + intermediate frequency secondary amplification". The weak terahertz noise signal is first amplified with low noise (to suppress the front end's own noise interference), and then narrowband intermediate frequency filtering is used to effectively filter out stray signals, environmental electromagnetic interference and local oscillator signal leakage in the terahertz band, ensuring the purity of the signal entering the power detection equipment.

[0031] 2. The narrowband intermediate frequency output design reduces the impact of "wideband noise superposition" on the test results. Combined with the power detection capability of the high-precision spectrum analyzer, the noise power measurement error is controlled within ±0.01dB, which meets the performance calibration requirements in the R&D stage and the accuracy screening requirements in the mass production stage of terahertz low noise amplifier chips.

[0032] The present invention will now be described in further detail with reference to the accompanying drawings. Attached Figure Description

[0033] Figure 1 This is a schematic diagram of the architecture of the noise figure test receiving front end of a terahertz low-noise amplifier chip in one embodiment.

[0034] Figure 2 This is a schematic diagram of the test architecture of a noise figure test system for a terahertz low-noise amplifier chip in one embodiment. Detailed Implementation

[0035] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0036] Existing technologies employ solid-state noise sources paired with noise meters or utilize vector network noise (VRF) options to conduct noise figure testing of low-noise amplifier chips. However, for noise figure testing above 50GHz, traditional methods use high-frequency solid-state noise sources and frequency converter modules paired with noise meters. However, the high cost and limited operating frequencies of commercially available solid-state noise sources restrict the testing frequency range of the system. To address this issue, a hot / cold source approach can be used to test the noise figure of terahertz low-noise amplifier chips. This method effectively expands the testing frequency range and is relatively inexpensive. For accurate testing using this method, the design of the receiving front-end is crucial. This invention proposes a design and implementation method for a high-precision receiving front-end module.

[0037] In one embodiment, combined Figure 1 A receiving front-end for testing the noise figure of a low-noise amplifier chip is provided. The receiving front-end includes an antenna, a device under test (DUT), a terahertz low-noise amplifier, a terahertz mixer module, a signal source frequency multiplier component, an intermediate frequency (IF) amplifier module, an IF filter module, and a spectrum analyzer. The output of the antenna is connected to the input of the DUT, the output of the DUT is connected to the input of the terahertz low-noise amplifier, the output of the terahertz low-noise amplifier is connected to the RF input of the terahertz mixer module, the output of the signal source frequency multiplier component is connected to the local oscillator input of the terahertz mixer module, the output of the terahertz mixer module is connected to the input of the IF amplifier module, the output of the IF amplifier module is connected to the input of the IF filter module, and the output of the IF filter module is connected to the input of the spectrum analyzer.

[0038] The antenna is used to receive terahertz hot and cold source radiation power and transmit the received radiation power signal to the device under test.

[0039] The terahertz low-noise amplifier is used to amplify the signal output by the device under test in a low-noise manner and transmit it to the terahertz mixer module.

[0040] The signal source frequency multiplier component is used to provide a local oscillator signal that meets the frequency requirements and transmit it to the terahertz mixing module to mix with the terahertz noise signal after being amplified by the terahertz low-noise amplifier.

[0041] The terahertz mixer module is used to convert terahertz noise signals into intermediate frequency signals.

[0042] The intermediate frequency amplification module is used to amplify the intermediate frequency signal after frequency conversion;

[0043] The intermediate frequency filtering module is used to filter out noise and interference signals in the amplified intermediate frequency signal;

[0044] The spectrum analyzer is used to detect the filtered intermediate frequency signal and display the intermediate frequency output power.

[0045] This receiving front end is mainly used in terahertz noise figure testing systems for hot and cold sources, and is adapted to the testing scenario requirements of terahertz hot and cold source radiation power.

[0046] Preferably, in some embodiments, the receiving front end adopts a double-sideband receiving method. Here, no filter is added before mixing, so it is not determined whether it is an up-mixing or down-mixing mode. Therefore, the double-sideband receiving method adopted in this invention simplifies the system structure to a certain extent.

[0047] Preferably, in some embodiments, the frequency of the local oscillator signal is matched with the frequency of the terahertz noise signal to achieve effective mixing.

[0048] Preferably, in some embodiments, the signal source frequency multiplier component includes:

[0049] The signal source is used to output a basic signal and transmit it to the frequency multiplier;

[0050] The frequency multiplier is used to multiply the frequency of the basic signal, generate a local oscillator signal, and transmit it to the terahertz mixer module to mix with the terahertz noise signal after being amplified by the terahertz low-noise amplifier.

[0051] The output of the signal source is connected to the input of the frequency multiplier, and the output of the frequency multiplier is connected to the local oscillator input of the terahertz mixer module.

[0052] Preferably, in some embodiments, the antenna is a terahertz band dedicated corrugated antenna, and the operating frequency band of the corrugated antenna is consistent with the frequency band of the terahertz hot and cold source radiation power.

[0053] Preferably, in some embodiments, the filtering frequency band of the intermediate frequency filtering module is 100MHz-500MHz, mainly considering that the noise figure of the device under test changes little within this frequency band, which can improve the system testing accuracy.

[0054] Preferably, in some embodiments, the spectrum analyzer is a power detection device with an accuracy of not less than 0.02dB, used to achieve high-precision acquisition of intermediate frequency output power.

[0055] Preferably, in some embodiments, the output power of the intermediate frequency amplification module is greater than 0 dBm to meet the detection sensitivity requirements of the spectrum analyzer and ensure the accuracy of the intermediate frequency output power data.

[0056] Preferably, in some embodiments, the terahertz low-noise amplifier needs to control its own noise introduction during the low-noise amplification process to avoid affecting the test accuracy of the noise figure of the device under test.

[0057] In one embodiment, a noise figure testing system for a low-noise amplifier chip is provided, the system including the receiving front end, and further including:

[0058] The test output module is used to calculate and obtain the noise figure of the device under test based on the intermediate frequency output power data.

[0059] The specific working process of the test system is as follows: the antenna receives the radiated power of the terahertz hot and cold sources and transmits the received radiated power signal to the device under test (DUT); the signal output by the DUT enters the terahertz low-noise amplifier (LNA), which amplifies the signal with low noise; the signal source outputs a basic signal and transmits it to the frequency multiplier, which performs frequency multiplication to generate a local oscillator signal and transmits it to the terahertz mixer module; the terahertz noise signal amplified by the LNA and the local oscillator signal output by the frequency multiplier are mixed in the terahertz mixer module, which converts the terahertz noise signal into an intermediate frequency (IF) signal; the IF amplification module amplifies the IF signal and transmits it to the IF filtering module, which filters out noise and interference signals in the IF signal; the spectrum analyzer detects the filtered IF signal and displays the IF output power; based on the IF output power data detected by the spectrum analyzer, the noise figure of the DUT is calculated using, but not limited to, the Y-factor method.

[0060] As a specific example, the invention will be described in detail in one embodiment.

[0061] In this embodiment, the terahertz receiving front-end is frequency multiplied by 24, and the signal source power ranges from 0 to 5 dBm, which can drive the corresponding link to work normally.

[0062] The testing process is as follows:

[0063] (1) Set the cold and heat sources and wait for them to stabilize to the target temperature;

[0064] (2) Set the signal source frequency and the terahertz receiving front-end frequency and power;

[0065] (3) During the calibration process, the antenna is moved below the cold source. When the antenna is below the cold source, the system power of the system formed by the antenna-terahertz receiving front end is: The antenna is moved below the heat source. When the antenna is below the heat source, the system power of the system formed by the antenna-terahertz receiving front end is: ;

[0066] (4) During the test, the low-noise amplifier under test is connected to the back of the antenna. The antenna is moved to a position below the cold source. When the antenna is below the cold source, the system power of the system formed by the antenna-DUT-terahertz receiving front end is: The motion stage is controlled to move the antenna below the heat source. When the antenna is below the heat source, the system power of the system formed by the antenna, the device under test, and the terahertz receiving front end is: ;

[0067] (5) Calculate the noise figure of the low-noise amplifier module of the device under test.

[0068]

[0069]

[0070]

[0071] In the formula, Boltzmann's constant, For receiver system bandwidth, For receiver noise temperature, For receiver gain, For the Y factor, , This represents the system power when the antenna is in both hot and cold source states during the calibration process. , Set the temperatures for the cold source and the heat source respectively;

[0072] Define the noise factor of the receiving system. Where T0 is the set ambient temperature of 298K, the above formula is transformed to obtain:

[0073]

[0074] During the measurement process, the device under test (DUT) is connected between the antenna and the receiving system, forming a cascaded system. The first stage is the DUT, and the second stage consists of the receiving front-end and the power detection device (the terahertz low-noise amplifier before the mixer is already part of the receiving front-end and does not need to be calculated separately). Based on the above formula, the total noise factor of the cascaded system can be calculated as follows:

[0075]

[0076] In the formula, This represents the total noise factor of the cascaded system.

[0077] The total noise factor of the cascaded system can be calculated using the noise cascade formula:

[0078]

[0079] In the formula, and The units are all in K. The corresponding room temperature is 298K; The noise factor of the antenna is denoted as , and for passive devices, the noise factor is denoted as , which ... This represents the antenna insertion loss. The noise factor of the assembled low-noise amplifier module under test; To obtain the gain of the assembled low-noise amplifier module, we can combine the two formulas above to get:

[0080]

[0081]

[0082]

[0083] In the formula, The noise factor of the assembled low-noise amplifier module. The noise figure of the low-noise amplifier module under test (DUT) is given. and Set the temperature for the cold and heat sources respectively. The corresponding room temperature is 298K. and This represents the system power when the antenna is in both cold and hot source states during the test. The noise factor of the antenna. To adjust the gain of the assembled low-noise amplifier module, To receive the system noise factor, specifically:

[0084]

[0085] The signal source proposed in this invention provides the fundamental signal of the terahertz receiving front end, and the frequency required for testing is obtained by connecting the signal source to the frequency multiplier designed in the receiving front end.

[0086] Taking the testing of the noise figure of the low-noise amplifier chip at 330GHz as an example, the above test process is as follows:

[0087] The frequency multiplier is designed to be 24 times the normal frequency.

[0088] A noise figure testing system was set up, with the spectrum analyzer frequency set to 128MHz, the terahertz receiver front-end parameters set to 330GHz, 0dBm drive, and the signal source automatically generating the basic signal.

[0089] Perform system calibration, such as Figure 1 Connect to the test system, cold source temperature 79.15K, heat source temperature 296.15K, the control system controlled the moving platform to detect the power of the cold and hot sources respectively. -20.93dBm and -20.73dBm.

[0090] Place the test piece as follows Figure 2 Connect to the test system, set the operating voltage to ensure the low-noise amplifier operates normally, and then collect power data corresponding to different hot and cold source states. -4.54 dBm and -4.45 dBm.

[0091] The noise figure of the device under test at the current frequency can be obtained by calculating using the formula in this invention. It is 6.88dB.

[0092] By setting different frequencies and repeating the above steps, the noise figure within the corresponding frequency band can be measured.

[0093] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention without departing from its spirit and scope should be included within the protection scope of the present invention.

Claims

1. A low-noise amplifier chip noise figure test receiving front end, characterized in that, The receiving front end includes an antenna, a device under test (DUT), a terahertz low-noise amplifier (THA), a terahertz mixer module, a signal source frequency multiplier, an intermediate frequency (IF) amplifier module, an IF filter module, and a spectrum analyzer. The output of the antenna is connected to the input of the DUT, the output of the DUT is connected to the input of the terahertz low-noise amplifier (THA), the output of the THA is connected to the RF input of the terahertz mixer module, the output of the signal source frequency multiplier is connected to the local oscillator input of the terahertz mixer module, the output of the terahertz mixer module is connected to the input of the IF amplifier module, the output of the IF amplifier module is connected to the input of the IF filter module, and the output of the IF filter module is connected to the input of the spectrum analyzer. The antenna is used to receive terahertz hot and cold source radiation power and transmit the received radiation power signal to the device under test. The terahertz low-noise amplifier is used to amplify the signal output by the device under test in a low-noise manner and transmit it to the terahertz mixer module. The signal source frequency multiplier component is used to provide a local oscillator signal that meets the frequency requirements and transmit it to the terahertz mixing module to mix with the terahertz noise signal after being amplified by the terahertz low-noise amplifier. The terahertz mixer module is used to convert terahertz noise signals into intermediate frequency signals. The intermediate frequency amplification module is used to amplify the intermediate frequency signal after frequency conversion; The intermediate frequency filtering module is used to filter out noise and interference signals in the amplified intermediate frequency signal; The spectrum analyzer is used to detect the filtered intermediate frequency signal and display the intermediate frequency output power.

2. The low-noise amplifier chip noise figure test receiving front end according to claim 1, characterized in that, The receiving front end adopts a double-sideband receiving method.

3. The low-noise amplifier chip noise figure test receiving front end according to claim 1, characterized in that, The frequency of the local oscillator signal is matched with the frequency of the terahertz noise signal.

4. The low-noise amplifier chip noise figure test receiving front end according to claim 1, characterized in that, The signal source frequency multiplier component includes: The signal source is used to output a basic signal and transmit it to the frequency multiplier; The frequency multiplier is used to multiply the frequency of the basic signal, generate a local oscillator signal, and transmit it to the terahertz mixer module to mix with the terahertz noise signal after being amplified by the terahertz low-noise amplifier. The output of the signal source is connected to the input of the frequency multiplier, and the output of the frequency multiplier is connected to the local oscillator input of the terahertz mixer module.

5. The low-noise amplifier chip noise figure test receiving front end according to claim 1, characterized in that, The antenna is a terahertz band-specific corrugated antenna, and the operating frequency band of the corrugated antenna is consistent with the frequency band of the terahertz cold and hot source radiation power.

6. The low-noise amplifier chip noise figure test receiving front end according to claim 1, characterized in that, The intermediate frequency filtering module has a filtering frequency band of 100MHz-500MHz.

7. The low-noise amplifier chip noise figure test receiving front end according to claim 1, characterized in that, The spectrum analyzer is a power detection device with an accuracy of not less than 0.02dB, used to achieve high-precision acquisition of intermediate frequency output power.

8. The low-noise amplifier chip noise figure test receiving front end according to claim 1, characterized in that, The output power of the intermediate frequency amplifier module is greater than 0 dBm.

9. The low-noise amplifier chip noise figure test receiving front end according to claim 1, characterized in that, The terahertz low-noise amplifier needs to control its own noise introduction during the low-noise amplification process.

10. A noise figure testing system for a low-noise amplifier chip, characterized in that, The system includes the receiving front end as described in any one of claims 1 to 8, and further includes: The test output module is used to calculate and obtain the noise figure of the device under test based on the intermediate frequency output power data.

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