Terahertz frequency multiplier testing system and method

Abstract

The invention discloses a terahertz frequency multiplier testing system and method, and belongs to the technical field of testing. According to the invention, the upper computer controls the test instrument to realize synchronous full-automatic data acquisition of the port output power and the output signal spectrum characteristic index of the terahertz frequency multiplier, so that the test efficiency of batch frequency multipliers is improved; a harmonic analysis algorithm and a K-Means clustering analysis algorithm integrated by a data processing unit of an upper computer are utilized to realize harmonic frequency analysis and performance index typical value clustering analysis, the performance indexes of the frequency multiplier are comprehensively presented, and research, development and iterative design of the terahertz frequency multiplier and a terahertz system are guided; according to the terahertz frequency multiplier test system based on the integration of the harmonic analysis algorithm and the K-Means clustering analysis algorithm, the test efficiency and test comprehensiveness of the performance indexes of the terahertz frequency multiplier are improved. According to the invention, the performance index test and analysis of the terahertz frequency multiplier can be realized more efficiently and comprehensively.

Description

Technical Field

[0001] The present invention belongs to the technical field of testing, and particularly relates to a terahertz frequency multiplier testing system and method. Background Art

[0002] A terahertz frequency multiplier is a two-port device that can boost the signal frequency to the terahertz band. It features a high operating frequency, a wide operating bandwidth, and a high harmonic order, making it a core device in terahertz systems. The key performance indicators of a terahertz frequency multiplier include the port output power, the spectral characteristics of the output signal, etc., which directly determine the overall performance indicators of the terahertz system. With the continuous development of terahertz technology, the operating frequency band of terahertz frequency multipliers based on solid-state electronics has been continuously rising and has reached 1.5 THz and above. Common testing methods can no longer meet the requirements for testing and analyzing the performance indicators of terahertz frequency multipliers.

[0003] Existing terahertz frequency multiplier testing systems have a simple structure and single function. They can usually only automatically collect the power data of the port output of the frequency multiplier. For the spectral characteristics testing of the output signal, due to the complexity of the data, generally only some spectral information is recorded by manually setting the test instrument point by point, resulting in low testing efficiency. It is difficult to achieve the efficient testing of the performance indicators of a batch of frequency multipliers and the comprehensive analysis of the output signal quality, which to a certain extent restricts the research, development, optimization, and iteration process of terahertz frequency multipliers and terahertz systems. Summary of the Invention

[0004] In view of the above technical problems existing in the prior art, the present invention proposes a terahertz frequency multiplier testing system and method, which is reasonably designed, overcomes the deficiencies of the prior art, and has good effects.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] A terahertz frequency multiplier testing system includes a terahertz power meter, a terahertz power probe, an 110 GHz spectrum analyzer, an 110 GHz signal generator, a terahertz spectrum analyzer frequency extension module, a terahertz local oscillator driving unit, a waveguide single directional coupler, a terahertz frequency multiplier testing port, a power probe connecting wire, a local oscillator wire, an intermediate frequency wire, a spectrum analyzer frequency extension control line, a communication bus, and a host computer; the local oscillator wire includes a first local oscillator wire and a second local oscillator wire;

[0007] The terahertz power meter is configured to process the power data detected by the terahertz power probe and display the power value in real time;

[0008] The terahertz power probe is configured to detect the magnitude of the terahertz signal power;

[0009] A 110GHz spectrum analyzer, configured to analyze, calculate, and display the spectrum of terahertz signals; provide a first local oscillator signal for the frequency expansion module of the terahertz spectrum analyzer; control the frequency expansion module of the terahertz spectrum analyzer to implement the frequency expansion function;

[0010] A 110GHz signal generator, configured to provide a second local oscillator signal for the terahertz local oscillator drive unit;

[0011] The frequency expansion module of the terahertz spectrum analyzer, configured to receive the terahertz signal distributed by the waveguide single directional coupler; implement the spectrum analysis expansion function under the control of the 110GHz spectrum analyzer;

[0012] The terahertz local oscillator drive unit, configured to provide excitation for the terahertz frequency multiplier and drive the terahertz frequency multiplier to start working;

[0013] The waveguide single directional coupler, configured to distribute the output power of the terahertz frequency multiplier to the terahertz signal spectrum analyzer and the terahertz power probe;

[0014] The test port of the terahertz frequency multiplier, configured to test the terahertz frequency multiplier to be measured;

[0015] The power probe connection line, configured to transmit the signal detected by the terahertz power probe to the receiving end of the terahertz power meter;

[0016] The first local oscillator line, configured to transmit the first local oscillator signal output by the 110GHz spectrum analyzer to the frequency expansion module of the terahertz spectrum analyzer as an excitation signal;

[0017] The second local oscillator line, configured to transmit the second local oscillator signal output by the 110GHz signal generator to the terahertz local oscillator drive unit as an excitation signal;

[0018] The intermediate frequency line, configured to transmit the intermediate frequency signal down-converted and output by the frequency expansion module of the terahertz spectrum analyzer to the receiving end of the 110GHz spectrum analyzer;

[0019] The spectrum analyzer frequency expansion control line: configured to transmit the intermediate frequency compensation data in the frequency expansion module of the terahertz spectrum analyzer to the 110GHz spectrum analyzer;

[0020] The communication bus, configured to implement data interaction and transmission between the upper computer and the test instrument;

[0021] The upper computer, configured to communicate with the terahertz power meter and the terahertz spectrum analyzer through the communication bus. The upper computer includes a processor and a memory. The memory stores instructions. When the instructions are executed by the processor, the upper computer performs the following operations:

[0022] Control the terahertz power meter and the terahertz spectrum analyzer to perform full-automatic data acquisition synchronously to obtain the output power and the output signal spectrum data of the terahertz frequency multiplier;

[0023] Execute a harmonic analysis algorithm on the output signal spectrum data to determine the harmonic order of the terahertz frequency multiplier;

[0024] Execute a K-Means clustering analysis algorithm on the output power and the output signal spectrum data to determine the typical performance indicators of the terahertz frequency multiplier;

[0025] Among them, the memory is further used to store the test data, and the host computer includes a display unit for real-time display of the test results.

[0026] In addition, the present invention also mentions a method for testing a terahertz frequency multiplier. This method uses a terahertz frequency multiplier test system as described above, and specifically includes the following steps:

[0027] Step 1: Before performing full-automatic data acquisition, set test parameters through the host computer; connect the host computer to the test instrument and confirm the communication status; power on and preheat, and the preheating duration is 30 minutes;

[0028] Step 2: Control the terahertz power meter and the terahertz spectrum analyzer to perform full-automatic data acquisition synchronously through the host computer to obtain the output power P_Rf and the output signal spectrum data of the terahertz frequency multiplier;

[0029] Step 3: Execute a harmonic analysis algorithm on the output signal spectrum data through the host computer to determine the harmonic order of the terahertz frequency multiplier;

[0030] Step 4: Execute a K-Means clustering analysis algorithm on the output power and the output signal spectrum data through the host computer to determine the typical performance indicators of the terahertz frequency multiplier;

[0031] Step 5: After the data processing module finishes processing, the working state of the host computer is STATE_0, close the communication port, that is, disconnect the instrument connection, release the instrument resources, and end the test.

[0032] Preferably, in step 1, the set parameters include the start frequency, the stop frequency, the number of local oscillator times, the number of radio frequency times, the signal power, the frequency resolution, and the data analysis algorithm.

[0033] Preferably, in step 2, the steps of controlling the terahertz power meter to perform full-automatic data acquisition through the host computer to obtain the output power P_Rf of the terahertz frequency multiplier are as follows:

[0034] After connecting and fixing the test port of the terahertz frequency doubler to the terahertz local oscillator driving unit and the waveguide single directional coupler, select the test state STATE_1 using the host computer, control the 110 GHz signal generator, the terahertz power meter, and the terahertz power probe to perform the output power test, and save it in the host computer as P_Rf.

[0035] Preferably, in step 2, the steps of controlling the terahertz spectrum analyzer by the host computer to perform full-automatic data acquisition to obtain the output signal spectrum data of the terahertz frequency doubler are as follows:

[0036] Select the test state STATE_2 using the host computer, control the 110 GHz signal generator to generate a local oscillator signal with a frequency of Freq_Lo to drive the terahertz frequency doubler to work. The output terahertz signal is analyzed and processed by the 110 GHz spectrum analyzer and the terahertz spectrum analyzer frequency expansion module and then displayed on the interface of the 110 GHz spectrum analyzer, and saved in the host computer, denoted as Freq_Harmonic.

[0037] Preferably, in step 3, perform a harmonic analysis algorithm on the output signal spectrum data through the host computer, perform harmonic number calculation, obtain all the harmonic signal numbers corresponding to the input signal Freq_Lo of the terahertz frequency doubler, and save it in the host computer, denoted as Num_Harmonic;

[0038] The formula of the harmonic analysis algorithm is as shown in (1):

[0039]

[0040] Among them, Num_Harmonic is the harmonic number of the terahertz frequency doubler; Freq_Lo is the input signal of the frequency doubler; Freq_Harmonic represents the output signal spectrum data of the terahertz frequency doubler.

[0041] Preferably, in step 4, the K-Means clustering analysis algorithm includes the following steps:

[0042] Step S1: Randomly select k data clusters from the test data;

[0043] Step S2: For each test data set x (i) , calculate its distance from each centroid μ j , and x (i) then belongs to the cluster c j of the centroid μ (j) that is closest to it, c (j) = argmin j ||x (i) - μ j || 2 , j ∈ 1, 2, …, k;

[0044] Step S3: For each class c (j) , recalculate the value of the cluster centroid:

[0045] Step S4: Repeat Step S2 and Step S3 until the algorithm converges; when the distortion function J in (c,μ) reaches the minimum value, c (j) and μ j converge simultaneously; at this time, the cluster c of the index data to be analyzed (j) is the typical value of the performance index of the terahertz frequency multiplier to be measured; where k represents the number of data clusters; x represents the test data set; l represents the modulus of the test data to the centroid; μ c represents the centroid of the test data set; c represents the data cluster.

[0046] Beneficial technical effects brought by the present invention:

[0047] (1) By controlling the test instrument through the host computer, synchronous full-automatic data acquisition of the output power and output signal spectrum characteristic indexes of the terahertz frequency multiplier port is realized, improving the test efficiency of batch frequency multipliers;

[0048] (2) Using the harmonic analysis algorithm and K-Means clustering analysis algorithm integrated in the host computer data processing unit to realize harmonic number analysis and typical value clustering analysis of performance indexes, presenting the performance indexes of the frequency multiplier more comprehensively, and guiding the research, development and iterative design of terahertz frequency multipliers and terahertz systems;

[0049] (3) The terahertz frequency multiplier test system based on the integration of the harmonic analysis algorithm and the K-Means clustering analysis algorithm improves the test efficiency and test comprehensiveness of the performance indexes of the terahertz frequency multiplier.

[0050] (4) Compared with the traditional terahertz frequency multiplier test method, it can more efficiently and comprehensively realize the performance index test and analysis of the terahertz frequency multiplier. Brief Description of the Drawings

[0051] Figure 1 is the block diagram of the test system of the present invention;

[0052] Figure 2 is the flowchart of the method of the present invention. Detailed Embodiments

[0053] The present invention will be further described in detail below in conjunction with the drawings and specific embodiments:

[0054] Embodiment 1

[0055] The present invention proposes a terahertz frequency multiplier test system, and this test system is asFigure 1 As shown in the figure, the test system includes a terahertz power meter, a terahertz power probe, an 110GHz spectrum analyzer, an 110GHz signal generator, a terahertz spectrum analyzer frequency extension module, a terahertz local oscillator drive unit, a waveguide single directional coupler, a terahertz frequency multiplier test port, a power probe connection line, a local oscillator line, an intermediate frequency line, a spectrum analyzer frequency extension control line, a communication bus, and a host computer; the local oscillator line includes a first local oscillator line and a second local oscillator line.

[0056] The terahertz power meter is configured to process the power data detected by the terahertz power probe and display the power value in real time.

[0057] The terahertz power probe is configured to detect the magnitude of the terahertz signal power.

[0058] The 110GHz spectrum analyzer is configured to analyze, calculate, and display the spectrum of the terahertz signal, provide a first local oscillator signal for the terahertz spectrum analyzer frequency extension module, and control the terahertz spectrum analyzer frequency extension module to implement the frequency extension function.

[0059] The 110GHz signal generator is configured to provide a second local oscillator signal for the terahertz local oscillator drive unit.

[0060] The terahertz spectrum analyzer frequency extension module is configured to receive the terahertz signal distributed by the waveguide single directional coupler and implement the spectrum analysis extension function under the control of the spectrum analyzer host.

[0061] The terahertz local oscillator drive unit is configured to provide excitation for the terahertz frequency multiplier and drive the terahertz frequency multiplier to start working.

[0062] The waveguide single directional coupler is configured to distribute the output power of the terahertz frequency multiplier to the terahertz signal spectrum analyzer and the terahertz power probe.

[0063] The terahertz frequency multiplier test port is configured to test the terahertz frequency multiplier to be measured.

[0064] The power probe connection line is configured to transmit the signal detected by the terahertz power probe to the receiving end of the terahertz power meter.

[0065] The first local oscillator line is configured to transmit the first local oscillator signal output by the 110GHz spectrum analyzer to the terahertz spectrum analyzer frequency extension module as an excitation signal.

[0066] The second local oscillator line is configured to transmit the second local oscillator signal output by the 110GHz signal generator to the terahertz local oscillator drive unit as an excitation signal.

[0067] The intermediate-frequency line is configured to transmit the intermediate-frequency signal output by the down-conversion of the frequency spreading module of the terahertz spectrum analyzer to the receiving end of the 110 GHz spectrum analyzer;

[0068] The frequency spreading control line of the spectrum analyzer is configured to transmit the intermediate-frequency compensation data in the frequency spreading module of the terahertz spectrum analyzer to the spectrum analyzer host;

[0069] The communication bus is configured to realize data interaction and transmission between the upper computer and the test instrument;

[0070] The upper computer is configured to run the upper computer software of the test system, perform data interaction with the test instrument through the communication bus, send instruction control signals to the signal generator to generate signals; and control the spectrum analyzer and the power meter to receive, analyze and process the collected test data.

[0071] Embodiment 2

[0072] Based on the above Embodiment 1, the present invention also mentions a method for testing a terahertz frequency multiplier (the process is as Figure 2 shown), which specifically includes the following steps:

[0073] Step 1: Test preparation. Set parameters including starting frequency, ending frequency, number of local oscillator times, number of radio frequency times, signal power, frequency resolution, and data analysis algorithm, connect the upper computer and the test instrument, and confirm the communication status; turn on the power and preheat for 30 minutes.

[0074] Step 2: Test the output power P_Rf of the terahertz frequency multiplier. After connecting and fixing the terahertz frequency multiplier to the driving unit and the coupler, use the upper computer control software to select the test state STATE_1, control the signal generator, the terahertz power meter and the power probe to perform the output power test, and save it in the upper computer as P_Rf.

[0075] Step 3: Collect the spectral characteristic data of the output signal of the terahertz frequency multiplier. Use the upper computer control software to select the test state STATE_2, control the signal generator to generate a local oscillator signal with a frequency of Freq_Lo to drive the terahertz frequency multiplier to work. The output terahertz signal is analyzed and processed by the spectrum analyzer and the frequency spreading module and then displayed on the spectrum analyzer interface, and saved in the upper computer as Freq_Harmonic.

[0076] Step 4: Analyze the harmonic order of the output signal. The data processing unit of the upper computer uses Algorithm 1, perform the harmonic order operation to obtain all the harmonic order signals corresponding to the input signal Freq_Lo of the frequency multiplier, and save it in the upper computer as Num_Harmonic.

[0077] Step 5: Cluster analysis of typical values of indicators: The data processing unit of the host computer uses Algorithm 2, the K-Means data clustering algorithm, to implement the clustering analysis of test results and obtain the typical values of the performance indicators of the terahertz frequency doublers produced in batches. This algorithm includes the following four steps: (1) Randomly select k data clusters from the test data; (2) For each test data set x (i) , it is necessary to calculate the distance from each centroid μ j . x (i) then belongs to the cluster c j of the centroid μ (j) to which it is closest. (3) For each class c (j) , recalculate the value of the centroid of this cluster: Repeat steps 2 and 3 until the algorithm converges. When the distortion function reaches the minimum value of J (c,μ) , c (j) and μ j converge simultaneously. At this time, the cluster c (j) of the indicator data to be analyzed is the typical value of the performance indicators of the terahertz frequency doubler to be tested, including the output signal power, the number of harmonics of the output signal, etc.

[0078] Step 6: After the data processing module finishes processing, the working state of the host computer is STATE_0, the communication port is closed, that is, the connection with the instrument is disconnected, the instrument resources are released, and the test ends.

[0079] 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 those skilled in the art within the scope of the essence of the present invention should also fall within the protection scope of the present invention.

Claims

1. A terahertz frequency doubler test system, characterized in that: It includes a terahertz power meter, a terahertz power probe, an 110GHz spectrum analyzer, an 110GHz signal generator, a terahertz spectrum analyzer frequency expansion module, a terahertz local oscillator drive unit, a waveguide single directional coupler, a terahertz frequency multiplier test port, a power probe connection line, a local oscillator line, an intermediate frequency line, a spectrum analyzer frequency expansion control line, a communication bus, and a host computer; the local oscillator line includes a first local oscillator line and a second local oscillator line; The terahertz power meter is configured to process the power data detected by the terahertz power probe; and display the power value in real time; The terahertz power probe is configured to detect the magnitude of the terahertz signal power; The 110GHz spectrum analyzer is configured to analyze, calculate, and display the spectrum of the terahertz signal; provide a first local oscillator signal for the terahertz spectrum analyzer frequency expansion module; and control the terahertz spectrum analyzer frequency expansion module to implement the frequency expansion function; The 110GHz signal generator is configured to provide a second local oscillator signal for the terahertz local oscillator drive unit; The terahertz spectrum analyzer frequency expansion module is configured to receive the terahertz signal allocated by the waveguide single directional coupler; and be controlled by the 110GHz spectrum analyzer to implement the spectrum analysis expansion function; The terahertz local oscillator drive unit is configured to provide excitation for the terahertz frequency multiplier and drive the terahertz frequency multiplier to start working; The waveguide single directional coupler is configured to distribute the output power of the terahertz frequency multiplier to the terahertz signal spectrum analyzer and the terahertz power probe; The terahertz frequency multiplier test port is configured to test the terahertz frequency multiplier to be measured; The power probe connection line is configured to transmit the signal detected by the terahertz power probe to the receiving end of the terahertz power meter; The first local oscillator line is configured to transmit the first local oscillator signal output by the 110GHz spectrum analyzer to the terahertz spectrum analyzer frequency expansion module as an excitation signal; The second local oscillator line is configured to transmit the second local oscillator signal output by the 110GHz signal generator to the terahertz local oscillator drive unit as an excitation signal; The intermediate frequency line is configured to transmit the intermediate frequency signal down-converted and output by the terahertz spectrum analyzer frequency expansion module to the receiving end of the 110GHz spectrum analyzer; The spectrum analyzer frequency expansion control line: is configured to transmit the intermediate frequency compensation data in the terahertz spectrum analyzer frequency expansion module to the 110GHz spectrum analyzer; The communication bus is configured to implement data interaction and transmission between the host computer and the test instruments; The host computer is configured to communicate with the terahertz power meter, the terahertz spectrum analyzer, and the 110GHz signal generator through the communication bus. The host computer includes a processor and a memory. The memory stores instructions. When the instructions are executed by the processor, the host computer performs the following operations: Control the terahertz power meter and the terahertz spectrum analyzer to synchronously perform full-automatic data acquisition to obtain the output power and output signal spectrum data of the terahertz frequency multiplier; Execute a harmonic analysis algorithm on the output signal spectrum data to determine the harmonic order of the terahertz frequency multiplier; Perform K-Means clustering analysis algorithm on the output power and output signal spectrum data to determine the typical performance indicators of the terahertz frequency multiplier; Among them, the memory is also used to store test data, and the host computer includes a display unit for real-time display of the test results.

2. A terahertz frequency doubler testing method, characterized in that: Adopt a terahertz frequency multiplier test system as described in claim 1, which specifically includes the following steps: Step 1: Before performing full-automatic data acquisition, set test parameters through the host computer; connect the host computer to the test instrument and confirm the communication status; turn on the power and preheat for 30 minutes. Step 2: Control the terahertz power meter and terahertz spectrum analyzer to perform full-automatic data acquisition synchronously through the host computer to obtain the output power P_Rf of the terahertz frequency multiplier and the output signal spectrum data. Step 3: Perform a harmonic analysis algorithm on the output signal spectrum data through the host computer to determine the harmonic order of the terahertz frequency multiplier. Step 4: Perform K-Means clustering analysis algorithm on the output power and output signal spectrum data through the host computer to determine the typical performance indicators of the terahertz frequency multiplier. Step 5: After the data processing module completes the processing, the working state of the host computer is STATE_0, close the communication port, that is, disconnect the instrument connection, release the instrument resources, and end the test.

3. The terahertz frequency doubler testing method according to claim 2, characterized in that: In step 1, the set parameters include start frequency, stop frequency, local oscillator frequency, RF frequency, signal power, frequency resolution, and data analysis algorithm.

4. The terahertz frequency doubler testing method according to claim 2, characterized in that: In step 2, the steps of controlling the terahertz power meter to perform full-automatic data acquisition through the host computer to obtain the output power P_Rf of the terahertz frequency multiplier are as follows: After connecting and fixing the test port of the terahertz frequency multiplier to the terahertz local oscillator driving unit and waveguide single directional coupler, use the host computer to select the test state STATE_1, control the 110GHz signal generator, terahertz power meter and terahertz power probe to perform output power test, and save it in the host computer as P_Rf.

5. The terahertz frequency doubler testing method according to claim 2, wherein: In step 2, the steps of controlling the terahertz spectrum analyzer to perform full-automatic data acquisition through the host computer to obtain the output signal spectrum data of the terahertz frequency multiplier are as follows: Use the host computer to select the test state STATE_2, control the 110GHz signal generator to generate a local oscillator signal with a frequency of Freq_Lo to drive the terahertz frequency multiplier to work. The output terahertz signal is analyzed and processed by the 110GHz spectrum analyzer and the terahertz spectrum analyzer frequency expansion module and then displayed on the 110GHz spectrum analyzer interface, and saved in the host computer as Freq_Harmonic.

6. The terahertz frequency doubler testing method according to claim 2, wherein: In step 3, perform a harmonic analysis algorithm on the output signal spectrum data through the host computer, perform harmonic order calculation, obtain all the harmonic signal orders corresponding to the input signal Freq_Lo of the terahertz frequency multiplier, and save it in the host computer as Num_Harmonic; The formula of the harmonic analysis algorithm is as shown in (1): Among them, Num_Harmonic is the harmonic order of the terahertz frequency multiplier; Freq_Lo is the input signal of the frequency multiplier; Freq_Harmonic represents the output signal spectrum data of the terahertz frequency multiplier.

7. The terahertz frequency doubler testing method according to claim 2, characterized in that: In step 4, the K-Means clustering analysis algorithm includes the following steps: Step S1: Randomly select k data clusters from the test data; Step S2: For each test data set x (i) , calculate the distance to each centroid μ j . x (i) then belongs to the cluster c j of the centroid μ (j) to which it is closest, where c (j) = argmin j ||x (i) - μ j || 2 , j ∈ 1, 2, …, k; Step S3: For each class c (j) , recalculate the value of the centroid of this cluster: Step S4: Repeat Step S2 and Step S3 until the algorithm converges; when the distortion function J (c,μ) reaches the minimum value, c (j) and μ j converge simultaneously; at this time, the cluster c (j) of the index data to be analyzed is the typical value of the performance index of the terahertz frequency doubler to be measured; where k represents the number of data clusters; x represents the test data set; l represents the modulus of the test data to the centroid; μ c represents the centroid of the test data set; c represents the data cluster.

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