A power adaptive closed-loop calibration method and system based on broadband frequency source

Abstract

The present invention discloses a power adaptive closed-loop calibration method and system based on a broadband frequency source. The method includes outputting a frequency signal after issuing a target frequency switching instruction, and using a detection circuit to detect the detection voltage of the frequency source when outputting the frequency signal; using a fitting parameter configuration unit to obtain the signal power value of the frequency source when outputting the frequency signal based on the detection voltage and the corresponding detection factor, and determining the power difference to be compensated; driving the radio frequency power configuration unit to control the signal output power until the power difference to be compensated is within a preset error range, and outputting a corrected frequency signal. The present invention uses a broadband detector to detect the output radio frequency signal of the broadband frequency source, and uses the detected output radio frequency signal of the broadband frequency source as a feedback loop to correct the calibration parameters, thereby solving the technical problems of traditional open-loop calibration technology, such as large workload, low efficiency, poor flexibility, and distorted product performance.

Description

Technical Field

[0001] The present invention relates to the technical field of broadband frequency source products, and in particular to a power adaptive closed-loop calibration method and system based on a broadband frequency source. Background Art

[0002] As an important component of electronic systems, broadband frequency sources mainly provide the system with accurate reference clock signals, large-bandwidth and high-dynamic correction signals, etc., and have extremely high requirements for signal amplitude flatness and accuracy. In some application scenarios, the output signal power of broadband frequency sources must meet certain fluctuation index requirements within the entire frequency band.

[0003] In order to solve the power flatness problem, a full-band ergodic power correction method is usually used to calibrate the output power of a broadband frequency source. Figure 1 This is a commonly used open-loop power calibration method for the entire frequency band. This calibration method consists of two steps: First, the host computer sends a frequency switching command, causing the broadband frequency source to output different frequencies. The spectrum analyzer then sends the test data for each frequency point, i.e., the uncalibrated power value, to the host computer. Second, the host computer calculates the difference between the uncalibrated power value and the target power value, obtains the power value that needs to be calibrated at each frequency, combines it into a calibration code table, and sends the code table to the broadband frequency source. The broadband frequency source stores the calibration code table in the module's memory. After power-on, it reads the calibration data from the memory to correct the current output signal's output power. This calibration method requires specific calibration software to obtain the product's output power, configure the calibration code table, and send it. By directly compensating the output power and superimposing a fixed calibration value at each frequency point, the final output reaches the target power. There is no feedback loop between the output and input ends, making this an open-loop calibration method.

[0004] Traditional open-loop calibration technology performs calibration operations before the broadband frequency source product is delivered. The calibration code table is pre-stored in the product's internal storage device. Each time the module is enabled, the pre-stored correction code table is read to complete power compensation. Once the calibration code table is written, it cannot be modified. This method has a simple structure and stable operation. Under ideal circumstances, it can achieve relatively satisfactory results. However, it has many limitations: First, each product needs to be manually calibrated, which is labor-intensive and inefficient. Second, the calibration code table cannot be changed once it is fixed, resulting in poor product flexibility and relatively rough calibration results. Third, due to changes in the operating environment and product aging, the module performance changes, and the initial calibration parameters are no longer applicable, resulting in distorted product performance. Summary of the Invention

[0005] The main purpose of the present invention is to provide a power adaptive closed-loop calibration method and system based on a broadband frequency source, aiming to solve the technical problems of the current traditional open-loop calibration technology, such as large workload, low efficiency, poor flexibility, and distortion of product performance.

[0006] To achieve the above object, the present invention provides a power adaptive closed-loop calibration method based on a broadband frequency source, the method comprising the following steps:

[0007] S1: After issuing the target frequency switching instruction, the frequency signal is output and the detection circuit is used to detect the detection voltage of the frequency source when outputting the frequency signal;

[0008] S2: using the fitting parameter configuration unit, based on the detection voltage and the corresponding detection factor, obtaining the signal power value of the frequency source when outputting the frequency signal;

[0009] S3: using a correction parameter configuration unit to determine a power difference to be compensated according to the signal power value;

[0010] S4: Determine whether the power difference to be compensated is within a preset error range. If not, drive the RF power configuration unit to control the signal output power until the power difference to be compensated is within the preset error range, and output the corrected frequency signal.

[0011] Optionally, the step of using a detection circuit to detect a detection voltage of the frequency source when the frequency source outputs a target frequency signal specifically includes:

[0012] The detection circuit detects the analog detection voltage U corresponding to the output power of the frequency source when it outputs the target frequency signal. check ;

[0013] The analog voltage is converted into a digital detection voltage V that can be processed by the FPGA on the module through the AD conversion circuit. check .

[0014] Optionally, the expression for obtaining the signal power value of the frequency source when outputting the target frequency signal based on the detection voltage and the corresponding detection factor is:

[0015] V check =Alog P out +B

[0016] Among them, V check is the detection voltage, A and B are the detection factors, P out is the signal power value.

[0017] Optionally, the step of determining the power difference to be compensated according to the signal power value specifically includes: calculating the power difference ΔP to be compensated in the correction parameter configuration unit adj , the expression is:

[0018] ΔP adj =|P out -P target |

[0019] Among them, P target is the output target power.

[0020] Optionally, the number of corrections n for the adaptive closed-loop calibration satisfies:

[0021] T adj =T freqdet +n*T sumdly

[0022] T adj ≤T target

[0023] Among them, T freqset T is the time required to output the frequency signal after the target frequency switching instruction is issued. sumdly T is the time required from outputting the frequency signal to completing a calibration process. target is the highest frequency interval during the frequency sweep.

[0024] Optional, T sumdly The expression is:

[0025] T sumdly =T delay1 +T delay2 +T delay3 +T delay4 +T delay5

[0026] Among them, T delay1 It represents the conversion time required by the detection circuit to convert the power value into the voltage value, T delay2 The conversion time required for the AD conversion circuit selected in the design to convert the analog signal into a digital signal, T delay3 T is the calculation time required to calculate the actual output power value through the fitting parameter configuration unit, delay4 T is the calculation time required by the correction parameter configuration unit to calculate the power value to be corrected, delay5 The processing time required to configure the output power attenuation value.

[0027] In addition, in order to achieve the above-mentioned purpose, the present invention also provides a power adaptive closed-loop calibration system based on a broadband frequency source, which includes a detection circuit, a fitting parameter configuration unit, a correction parameter configuration unit and a radio frequency power configuration unit for executing the power adaptive closed-loop calibration method based on a broadband frequency source as described above.

[0028] The embodiment of the present invention proposes a power adaptive closed-loop calibration method and system based on a broadband frequency source, which has the following beneficial effects:

[0029] (1) Simplifies the product calibration process and saves calibration resources. Traditional calibration technology requires the use of specific calibration software to perform calibration tasks before product delivery; this technology avoids this process and realizes automatic calibration of the entire frequency band during the normal use of the product.

[0030] (2) It has full-scenario and full-cycle adaptive calibration capabilities. Traditional calibration technology uses a fixed test calibration code table for calibration before product delivery, and the calibration parameters cannot be modified once determined; this technology performs adaptive calibration based on the current output power during the initial frequency sweep phase after each power-on of the product, and can achieve flexible calibration as the application scenario and usage time change.

[0031] (3) More accurate calibration effect. Traditional calibration technology has problems such as inaccurate calibration parameters and poor performance in actual use due to errors introduced by the test system and differences in application scenarios. This technology uses the product's internal circuit for closed-loop self-detection and self-compensation, which can effectively avoid externally introduced errors and improve the calibration effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 Schematic diagram of the full-band ergodic power open-loop calibration method;

[0033] Figure 2 Schematic diagram of the flow of the power adaptive closed-loop calibration method based on a broadband frequency source of the present invention;

[0034] Figure 3 Schematic diagram of the principle of the adaptive closed-loop calibration of the present invention;

[0035] Figure 4 Schematic diagram of the open-loop and closed-loop calibration results of the present invention.

[0036] The purpose, features and advantages of the present invention will be further described with reference to the accompanying drawings and in conjunction with the embodiments. DETAILED DESCRIPTION

[0037] It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0038] At present, in the relevant technical field, the existing traditional open-loop calibration technology has a large workload, low efficiency, poor flexibility, and distorted product performance.

[0039] To address this issue, various embodiments of a power adaptive closed-loop calibration method and system based on a broadband frequency source are proposed. The power adaptive closed-loop calibration method and system based on a broadband frequency source provided by the present invention utilize a broadband detector to detect the output RF signal of the broadband frequency source, and use the detected output RF signal of the broadband frequency source as a feedback loop to correct the calibration parameters. This solves the technical problems of traditional open-loop calibration technology, such as high workload, low efficiency, poor flexibility, and distorted product performance.

[0040] The embodiment of the present invention provides a power adaptive closed-loop calibration method based on a broadband frequency source, referring to Figure 2 , Figure 2 The figure is a flow chart of an embodiment of a power adaptive closed-loop calibration method based on a broadband frequency source according to the present invention.

[0041] In this embodiment, the power adaptive closed-loop calibration method based on a broadband frequency source includes the following steps:

[0042] S1: After issuing the target frequency switching instruction, the frequency signal is output and the detection circuit is used to detect the detection voltage of the frequency source when outputting the frequency signal;

[0043] S2: using the fitting parameter configuration unit, based on the detection voltage and the corresponding detection factor, obtaining the signal power value of the frequency source when outputting the frequency signal;

[0044] S3: using a correction parameter configuration unit to determine a power difference to be compensated according to the signal power value;

[0045] S4: Determine whether the power difference to be compensated is within a preset error range. If not, drive the RF power configuration unit to control the signal output power until the power difference to be compensated is within the preset error range, and output the corrected frequency signal.

[0046] This embodiment utilizes a broadband detector to detect the output RF signal of a broadband frequency source, and uses the detected output RF signal of the broadband frequency source as a feedback loop to correct the calibration parameters. This system has the ability to automatically correct deviations in the controlled quantity, and can correct errors caused by changes in component parameters and external disturbances, thereby achieving better control effects and higher control accuracy.

[0047] The detector detection voltage value used in this embodiment has a conversion relationship with the detected power value:

[0048] V o =A log P i +B

[0049] Adaptive calibration process Figure 3When the broadband frequency source switches to the target frequency, the detection circuit detects the output power at the frequency point and obtains the corresponding analog detection voltage U check , through fast AD, the analog voltage is converted into a digital detection voltage V that can be processed by the FPGA on the module check ; In the fitting parameter configuration unit, the detection factors A and B are used to calculate the current module output signal power value P out ; Calculate the power difference ΔP to be compensated in the correction parameter configuration unit adj , the calculation formula is:

[0050] ΔP adj =|P out -P target |

[0051] Among them, P target Is the output target power. If ΔP adj If the error is within the allowable error range ΔP, the current output is maintained. If the error is greater than the error range ΔP, the signal output power is controlled in the RF power configuration unit, and the output signal power of the RF output port is finally adjusted to the target range.

[0052] It takes a certain amount of time for the adaptive closed-loop calibration technology to complete the calibration work. adj , T adj The value of is expressed as:

[0053] T adj =T freqset +n*T sumdly

[0054] Where T freqset It is the time from when the frequency switching instruction is issued to when the output signal is established. This time is mainly determined by the locking time of the phase-locked loop chip. sumdly The time required to complete the calibration process from output signal establishment to final completion is defined as:

[0055] T sumdly =T delay1 +T delay2 +T delay3 +T delay4 +T delay5

[0056] Where T delay1 It represents the conversion time required by the detection circuit to convert the power value into the voltage value, T delay2 The conversion time required for the AD chip selected for the design to convert the analog signal into a digital signal, T delay3 T is the calculation time required to calculate the actual output power value through the fitting parameter configuration unit, delay4T is the calculation time required by the correction parameter configuration unit to calculate the power value to be corrected, delay5 The processing time required to configure the output power attenuation value.

[0057] Since the closed-loop control system has the risk of "oscillation", this embodiment limits the number of corrections to n times. The value of n is related to the system requirements. The system requires that the frequency interval during the sweep period is not higher than T target , then the time required for correction of this process is T adj Should not be greater than T target , from which the value of n can be obtained. Generally, the output power can be corrected to the target power range through at most two correction steps.

[0058] This embodiment adopts a power adaptive closed-loop calibration method of a broadband frequency source to use the module's output signal as a feedback loop to adjust the correction parameters, automatically adjust the attenuation, and correct the product's output signal power to a range that meets system indicators.

[0059] This embodiment tests the output power of a broadband frequency source product before calibration, after open-loop calibration, and after adaptive closed-loop calibration. The results are as follows: Figure 4 The test results are shown.

[0060] As can be seen, both calibration methods can complete the calibration work, ensuring that the output signal of the broadband frequency source product meets the absolute output power and fluctuation index requirements within the operating frequency range. The amplitude fluctuation after closed-loop calibration is slightly better than that after open-loop calibration. Open-loop calibration requires the establishment of a dedicated test environment and the development of dedicated host computer software to complete the tasks of automatic power testing, calibration code table calculation, and calibration parameter distribution. Completing the calibration of a single product can take several hours. Closed-loop calibration automatically enters the calibration process during the normal testing phase, eliminating the need for a separate calibration step. That is, the module calibration is completed synchronously after the frequency sweep.

[0061] By comparison, it can be found that the power adaptive closed-loop calibration technology involved in the present invention has the following characteristics:

[0062] This simplifies the product calibration process and saves calibration resources. Traditional calibration technology requires the use of specific calibration software before product delivery; this embodiment avoids this process and achieves automatic calibration of the entire frequency band during normal product use.

[0063] It has full-scenario, full-cycle adaptive calibration capabilities. Traditional calibration technology uses a fixed test calibration code table for calibration before product delivery. Once the calibration parameters are determined, they cannot be modified. This embodiment performs adaptive calibration based on the current output power during the initial frequency sweep phase after each power-on, allowing for flexible calibration as application scenarios and usage time change.

[0064] A more accurate calibration effect. Traditional calibration technology has problems with inaccurate calibration parameters and poor performance in actual use due to errors introduced by the test system and differences in application scenarios. This embodiment uses the product's internal circuit for closed-loop self-detection and self-compensation, which can effectively avoid externally introduced errors and improve the calibration effect.

[0065] In order to explain the present application more clearly, a specific example of a power adaptive closed-loop calibration method based on a broadband frequency source is proposed.

[0066] During the development of a certain product, this embodiment was used to calibrate a broadband frequency source, simplifying the debugging process, reducing the debugging cycle, and improving product performance. Taking a broadband frequency source product with an operating frequency range of 0.35 GHz to 18 GHz as an example, with a total of 1966 frequency points in a 10 MHz step and a sweep interval of 200 μs per frequency point, it only takes 0.393 seconds to complete the calibration of a single product. That is, the product calibration is completed synchronously after the sweep is completed. Table 1 compares the open-loop and closed-loop calibration of the broadband frequency source product.

[0067] Table 1: Comparison of open-loop and closed-loop calibration results for a broadband frequency source product

[0068]

[0069] This embodiment provides a power adaptive closed-loop calibration method based on a broadband frequency source, which uses a broadband detector to detect the output RF signal of the broadband frequency source, and uses the detected output RF signal of the broadband frequency source as a feedback loop to correct the calibration parameters. It solves the technical problems of traditional open-loop calibration technology such as large workload, low efficiency, poor flexibility, and distortion of product performance.

[0070] The above are only preferred embodiments of the invention and are not intended to limit the patent scope of the invention. Any equivalent structure or equivalent process transformation made using the contents of the invention description and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the invention.

Claims

1. A power adaptive closed-loop calibration method based on a broadband frequency source, characterized in that: The method comprises the following steps: S1: After issuing the target frequency switching instruction, the frequency signal is output and the detection circuit is used to detect the detection voltage of the frequency source when outputting the frequency signal; S2: Using the fitting parameter configuration unit, based on the detection voltage and the corresponding detection factor, obtain the signal power value of the frequency source when it outputs the frequency signal, expressed as follows: in, is the detection voltage, and is the detection factor, is the signal power value; S3: using a correction parameter configuration unit to determine a power difference to be compensated according to the signal power value; S4: Determine whether the power difference to be compensated is within a preset error range. If not, drive the RF power configuration unit to control the signal output power until the power difference to be compensated is within the preset error range, and output the corrected frequency signal.

2. The power adaptive closed-loop calibration method based on a broadband frequency source according to claim 1, characterized in that: The step of using a detection circuit to detect the detection voltage of the frequency source when it outputs the target frequency signal specifically includes: The detection circuit detects the analog detection voltage corresponding to the output power of the frequency source when it outputs the target frequency signal ; The analog voltage is converted into a digital detection voltage that can be processed by the FPGA on the module through the AD conversion circuit .

3. The power adaptive closed-loop calibration method based on a broadband frequency source according to claim 2, characterized in that: The step of determining the power difference to be compensated according to the signal power value specifically includes: calculating the power difference to be compensated in the correction parameter configuration unit , the expression is: in, is the output target power.

4. The power adaptive closed-loop calibration method based on a broadband frequency source according to claim 3, characterized in that: The number of corrections n of the adaptive closed-loop calibration satisfies: ≤ in, It is the time required to output the frequency signal after the target frequency switching instruction is issued. It is the time required from outputting the frequency signal to completing a calibration process. is the highest frequency interval during the sweep.

5. The power adaptive closed-loop calibration method based on a broadband frequency source according to claim 4, characterized in that: The expression is: in, It indicates the conversion time required by the detection circuit to convert the power value into the voltage value. The conversion time required for the AD conversion circuit selected for the design to convert the analog signal into a digital signal, is the calculation time required to calculate the actual output power value through the fitting parameter configuration unit, The calculation time required for the correction parameter configuration unit to calculate the power value to be corrected, The processing time required to configure the output power attenuation value.

6. A power adaptive closed-loop calibration system based on a broadband frequency source, the system comprising a detection circuit, a fitting parameter configuration unit, a correction parameter configuration unit and a radio frequency power configuration unit for executing the power adaptive closed-loop calibration method based on a broadband frequency source as described in any one of claims 1 to 5.

Images