Multi-GHz clock tree dynamic phase calibration system and deviation suppression method

Abstract

The invention provides a multi-GHz clock tree dynamic phase calibration system and a deviation suppression method, and relates to the technical field of high-speed electronic system clock synchronization. According to the multi-GHz clock tree dynamic phase calibration system based on standing wave integrity monitoring and the deviation suppression method, a phased array radar realizes accurate beam pointing through sub-picosecond clock synchronization of hundreds of array elements, and the compensation precision of the system for environmental interference in a radar cabin is greatly improved in a full temperature range of-40 DEG C to 65 DEG C; phase deviation caused by temperature is suppressed and reduced through dynamic phase calibration, and radar ranging errors are reduced; and cable vibration bending compensation is carried out, phase deviation caused by bending and vibration is compensated for aiming at cable bending and vibration scenes among array elements, the speed measurement precision is improved, and the high-precision distance measurement and speed measurement requirements are met.

Description

Multi-GHz Clock Tree Dynamic Phase Calibration System and Deviation Suppression Method Technical Field

[0001] This invention relates to the field of clock synchronization technology for high-speed electronic systems, specifically to a multi-GHz clock tree dynamic phase calibration system and a deviation suppression method. Background Technology

[0002] In high-frequency fields such as phased array radar, millimeter-wave imaging, 5G / 6G base stations and quantum computing control systems, the clock tree, as the core timing support, needs to achieve phase synchronization of less than 1ps. For example, phased array radar relies on the synchronization of hundreds of array element clocks to ensure accurate beam pointing, and millimeter-wave imaging systems require multi-channel clock phase consistency to improve resolution.

[0003] However, based on current technology, multi-GHz clock trees rely on closed-loop system correction via links. This error term is compensated along with other system error terms, making it impossible to separately identify the error proportion of the clock tree, resulting in a gap in real-time performance. In other words, existing multi-GHz clock tree designs cannot monitor and suppress impedance mismatch in real time, and cannot dynamically handle core interference in high-frequency scenarios. Summary of the Invention

[0004] (I) Technical Problems Solved In view of the shortcomings of the existing technology, the present invention provides a dynamic phase calibration system and deviation suppression method for multi-GHz clock trees, which solves the technical problem that existing multi-GHz clock tree designs cannot monitor and suppress impedance mismatch in real time.

[0005] (II) Technical Solution To achieve the above objectives, the present invention provides the following technical solution: Firstly, the present invention provides a multi-GHz clock tree dynamic phase calibration system, including a distributed directional coupler array, an adjustable capacitor matching network, a phase and frequency joint detection module, and a transmission line delay analysis module; wherein, the distributed directional coupler array is used to collect the amplitude ratio of the incident wave to the reflected wave and the current clock frequency in real time in the clock transmission line, and when the amplitude ratio is detected to be greater than a threshold, the adjustable capacitor matching network is triggered to start adjustment; the adjustable capacitor matching network is used to dynamically adjust the capacitance value, and suppress impedance mismatch by changing the terminal impedance of the clock transmission line; the phase and frequency joint detection module is used to detect the change in ambient temperature, the physical deformation parameters of the clock transmission line, and the dielectric constant parameter corresponding to the current clock frequency, and transmits the detected data to the transmission line delay analysis module in real time; the transmission line delay analysis module is used to calculate the delay predistortion based on the three data transmitted by the phase and frequency joint detection module and the data collected by the distributed directional coupler array, and converts the delay predistortion into a predistortion control signal and outputs it to the voltage-controlled delay line.

[0006] Preferably, the voltage-controlled delay line is connected in series between the clock source and the clock transmission line network to receive the pre-distortion control signal output by the transmission line delay analysis module, and injects a delay pre-distortion amount into the clock signal output by the clock source according to the pre-distortion control signal to compensate for the delay deviation of the clock transmission line network.

[0007] Preferably, the distributed directional coupler array is embedded in a key node of the clock transmission line, the key node being a PCB via and an SMA interface; the distributed directional coupler array is a microstrip directional coupler, the sampling frequency of the microstrip directional coupler being consistent with the clock frequency of the clock transmission line, the clock frequency being in the range of 1 GHz to 40 GHz.

[0008] Preferably, the phase and frequency joint detection module is further used to receive compensation input data, which includes transmission line type parameters, including coplanar waveguides with conductor backing, microstrip lines, and striplines; the compensation input data is used to calculate the dielectric constant parameter corresponding to the current clock frequency.

[0009] Preferably, the step of calculating the delay predistortion based on the three data transmitted by the phase and frequency joint detection module and the data acquired by the distributed directional coupler array includes: in, To delay the predistortion amount, This is the temperature compensation coefficient. The accuracy is 0.1 ps / ℃. For frequency compensation coefficients, The bending compensation coefficient is... As the reference frequency, The current clock frequency, The bending angle of the clock transmission line cable.

[0010] Preferably, the transmission line delay analysis module is further used to calculate the pre-distortion bit and convert the pre-distortion bit into a control signal output; wherein, the process of calculating the pre-distortion bit includes: calculating the predicted total clock transmission line delay, and fitting the pre-distortion amount based on the predicted total clock transmission line delay and the material phase temperature coefficient; wherein, the formula for calculating the predicted total clock transmission line delay is as follows: In the formula, This represents the predicted total clock transmission line delay; β and γ are calibration coefficients. The phase temperature coefficient of the material; This represents the inherent delay term of the clock transmission line; Where c is the length of the clock transmission line and c is the speed of light; It is the square root of the effective dielectric constant that varies with temperature and frequency, and it reflects the basic transmission delay of a signal under specific materials, lengths, temperatures, and frequencies. The phase temperature coefficient of the material; This refers to the cable bending angle.

[0011] Secondly, the present invention provides a method for suppressing dynamic phase deviation of a multi-GHz clock tree. This method is applied to the aforementioned multi-GHz clock tree dynamic phase calibration system. The method includes the following steps: acquiring incident and reflected wave signals at PCB vias and SMA interfaces of the clock transmission line through the distributed directional coupler array; and calculating the phase distortion based on the amplitude ratio |Γ| of the incident and reflected waves. The system determines whether the amplitude ratio |Γ| is greater than a threshold value. If it is, it drives the adjustable capacitor matching network to dynamically adjust the capacitor value until the amplitude ratio |Γ| is less than or equal to the threshold value. The temperature change ΔT is collected by the temperature sensor that uses both phase and frequency detection, and the cable bending angle is collected by the cable bending angle detection unit. It then calls the frequency-to-dielectric-constant mapping table to obtain the dielectric constant parameter corresponding to the current clock frequency f, and sets ΔT, The parameters f and dielectric constant are input into the multivariate delay compensation model of the transmission line delay analysis module to calculate the clock transmission line delay predistortion. The delay predistortion is determined by the transmission line delay analysis module. It is converted into a predistortion control signal and output to the voltage control delay line, which drives the voltage control delay line to inject a delay predistortion amount into the clock signal between the clock source and the clock transmission line network, thereby completing the clock tree phase calibration.

[0012] Preferably, the threshold value of the amplitude ratio is 0.1, and the adjustable capacitor matching network adjusts the capacitor value in steps of 0.1fF.

[0013] Preferably, the phase distortion The calculation formulas include: .

[0014] Preferably, the calculation of clock transmission line delay predistortion... ,include: in, To delay the predistortion amount, This is the temperature compensation coefficient. The accuracy is 0.1 ps / ℃. For frequency compensation coefficients, The bending compensation coefficient is... As the reference frequency, The current clock frequency, The bending angle of the clock transmission line cable.

[0015] (III) Beneficial Effects This invention provides a multi-GHz clock tree dynamic phase calibration system and deviation suppression method. Compared with the prior art, it has the following beneficial effects: The multi-GHz clock tree dynamic phase calibration system and deviation suppression method based on standing wave integrity monitoring in this application enables phased array radar to achieve precise beam pointing through sub-picosecond clock synchronization of hundreds of array elements. Regarding the compensation accuracy for environmental interference within the radar cabin, the system reduces and suppresses phase deviation caused by temperature through dynamic phase calibration within the full temperature range of -40℃ to 65℃, thereby reducing radar ranging errors. Cable vibration and bending compensation addresses the phase deviation caused by bending and vibration in scenarios involving cable bending and vibration between array elements, improving velocity measurement accuracy and meeting the requirements for high-precision ranging and velocity measurement. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 is a system architecture diagram of a multi-GHz clock tree dynamic phase calibration system according to an embodiment of the present invention. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention are described clearly and completely. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] This application provides a multi-GHz clock tree dynamic phase calibration system and deviation suppression method, which solves the technical problem that existing multi-GHz clock tree designs cannot monitor and suppress impedance mismatch in real time. This invention can not only eliminate hidden phase distortion caused by impedance mismatch, but also suppress the delay changes caused by temperature and bending to the sub-picosecond level, while reducing the dependence on high-cost connectors and cables, and achieving low-cost sub-picosecond synchronization.

[0020] The technical solutions in this application are designed to solve the aforementioned technical problems. The overall approach is as follows: The multi-GHz clock tree dynamic phase calibration system and deviation suppression method based on standing wave integrity monitoring provided in this application enable the phased array radar to achieve precise beam pointing through sub-picosecond clock synchronization of hundreds of array elements. The system addresses the compensation accuracy for environmental interference within the radar cabin. Within the full temperature range of -40℃ to 65℃, dynamic phase calibration suppresses and reduces phase deviation caused by temperature, thereby reducing radar ranging errors. Cable vibration and bending compensation addresses scenarios involving cable bending and vibration between array elements, compensating for phase deviations caused by bending and vibration, thus improving velocity measurement accuracy and meeting the requirements for high-precision ranging and velocity measurement.

[0021] To better understand the above technical solutions, the following will provide a detailed explanation of the technical solutions in conjunction with the accompanying drawings and specific implementation methods.

[0022] Example 1: This example provides a multi-GHz clock tree dynamic phase calibration system based on standing wave integrity monitoring, as shown in Figure 1. The system includes a distributed directional coupler array, an adjustable capacitor matching network, a phase and frequency joint detection module, and a transmission line delay analysis module.

[0023] The distributed directional coupler array continuously monitors the amplitude ratio of the incident wave to the reflected wave in the clock transmission line. When the amplitude ratio is greater than a threshold, it triggers the adjustable capacitor matching network to start adjustment. The adjustable capacitor matching network dynamically adjusts the capacitance value to suppress impedance mismatch by changing the termination impedance of the clock transmission line. The phase and frequency joint detection module detects the change in ambient temperature, the physical deformation parameters of the clock transmission line, and the dielectric constant parameter corresponding to the current clock frequency f, and transmits these three data points to the transmission line delay analysis module in real time. The transmission line delay analysis module calculates the delay predistortion based on the three data points transmitted by the phase and frequency joint detection module and the data collected by the distributed directional coupler array, and converts the delay predistortion into a predistortion control signal to be output to the voltage-controlled delay line.

[0024] The following is a detailed description of each module of the multi-GHz clock tree dynamic phase calibration system: Distributed directional coupler array: In the specific implementation process, the distributed directional coupler array collects the amplitude ratio |Γ| of the incident wave and the reflected wave in real time at key nodes such as PCB vias and SMA interfaces of the clock transmission line, continuously monitoring the standing wave characteristics of the clock transmission line; when |Γ|>0.1 is detected (it should be noted that the threshold can be set according to the system frequency and accuracy requirements. Usually, 0.1 can meet the needs of mainstream systems), the signal triggers the adjustable capacitor matching network to start adjustment. At the same time, the monitoring frequency is synchronized with the operating frequency (1-40GHz) of the clock transmission line to ensure accurate capture of the standing wave characteristics of high-frequency signals.

[0025] In this embodiment, the distributed directional coupler array is a microstrip directional coupler, and the sampling frequency of the microstrip directional coupler is consistent with the clock frequency of the clock transmission line, wherein the clock frequency ranges from 1 GHz to 40 GHz.

[0026] Specifically, the microstrip structure adapts to the compact layout of key nodes of the clock transmission line (PCB vias, SMA interfaces), can be directly integrated into the PCB substrate, and has low loss characteristics in multiple GHz bands (1-40GHz), avoiding the impact of poor structural adaptability or excessive loss on the accuracy of standing wave monitoring.

[0027] The purpose of aligning the sampling frequency with the clock frequency is to ensure real-time, distortion-free capture of the amplitude changes of the incident or reflected wave in each clock cycle, calculate the standing wave ratio (VSWR), avoid missing instantaneous VSWR peak values ​​due to asynchronous sampling, and ensure that the adjustable capacitor matching network can trigger impedance mismatch suppression in a timely manner.

[0028] The 1GHz-40GHz frequency range covers the core clock band for system target applications (phased array radar, millimeter-wave imaging, etc.).

[0029] Adjustable capacitor matching network: Upon receiving the start command from the distributed directional coupler array, the adjustable capacitor matching network starts adjustment: dynamically adjusting the capacitor value in a minimum step of 0.1fF, gradually reducing the intensity of reflected waves by changing the transmission line termination impedance until |Γ|≤0.1. By optimizing impedance matching, reflected waves are suppressed, and the interference of standing waves on the phase is reduced, thus suppressing the phase distortion caused by standing waves from the source.

[0030] Phase and frequency joint detection module: The phase and frequency joint detection module includes an integrated temperature sensor and a cable bending angle detection unit, and the module has a pre-stored frequency-dielectric constant mapping table.

[0031] It should be noted that the phase and frequency joint detection module operates synchronously with the two modules mentioned above: it acquires the temperature change ΔT (covering the operating range of -40℃ to 85℃) through an integrated temperature sensor; it acquires the physical deformation parameter θ_bend of the transmission line (such as a bending angle of 0° to 90°) through a cable bending angle detection unit; and it extracts the dielectric constant parameter corresponding to the current clock frequency f by combining the frequency and dielectric constant mapping table. These parameters are transmitted to the transmission line delay analysis module in real time as the basic input for compensating for phase delay caused by temperature, bending, and frequency changes.

[0032] In this embodiment, the compensation input for joint phase and frequency detection includes clock transmission line type parameters, wherein the clock transmission line type includes coplanar waveguides with conductor backing, microstrip lines, and striplines; the frequency-to-dielectric constant mapping table is obtained by offline calibration of 1GHz and 40GHz multi-frequency S-parameter sweep using clock transmission lines with low dielectric constant (Dk<3.7) and low loss factor (DF<0.005) materials, wherein the low dielectric constant material includes Rogers4003C.

[0033] Clock transmission line materials with low dielectric constant (Dk<3.7) and low loss factor (DF<0.005) can reduce dielectric loss and characteristic fluctuations at high frequencies. A low Dk means a small rate of change of dielectric constant with frequency / temperature (the Dk temperature change rate of Rogers4003C is <0.01% / ℃), and a low DF means small signal attenuation (attenuation ≤0.2dB / cm at 40GHz), ensuring a stable relationship between frequency and dielectric constant during calibration and preventing data distortion.

[0034] The Rogers 4003C material has a Dk≈3.38 and DF≤0.0027, which fully meets the requirements of "low Dk and low DF". It also supports the fabrication of three types of clock transmission lines. The calibration data can be directly used for delay compensation calculation of different clock transmission lines in the system, ensuring that the mapping table is consistent with the actual application scenario.

[0035] Transmission line delay analysis module: This module receives two types of signals: |Γ| from the coupler array (reflecting phase distortion caused by standing waves) and ΔT from the joint detection module. f (reflecting the phase shift caused by environmental and physical factors) calculates the required delay predistortion based on a preset multivariate delay compensation model, converts it into a predistortion control signal, and outputs it to the voltage-controlled delay line.

[0036] Ultimately, the voltage-controlled delay line actively injects a reverse delay predistortion amount before the signal output from the clock source enters the clock transmission line network, based on the predistortion control signal. This precisely offsets the comprehensive delay deviation of the clock transmission line network caused by standing waves, temperature, bending, and frequency changes, thereby achieving dynamic calibration of the clock signal phase.

[0037] In this embodiment, the multivariate delay compensation model executed by the transmission line delay analysis module is as follows: in, To delay the predistortion amount, This is the temperature compensation coefficient. The accuracy is 0.1 ps / ℃. For frequency compensation coefficients, The bending compensation coefficient is... As the reference frequency, , , All coefficients were obtained through offline calibration using multi-frequency S-parameter sweep at 1GHz and 40GHz. This offline calibration, employing multi-frequency S-parameter sweep at 1GHz-40GHz, ultimately provides a delay predistortion control signal for the VCDL to compensate for overall delay deviations and ensure clock signal phase consistency. The 1GHz-40GHz range covers the system's operating frequency band, ensuring the coefficients are effective across the entire band. The offline environment allows for precise control of variables such as temperature and bending angle. By measuring transmission delays under different conditions, the optimal values ​​of β and γ are fitted, avoiding calibration errors caused by on-site interference.

[0038] In this embodiment, the operating temperature range of the phase and frequency joint detection is -40°C to 85°C; when the cable bending angle is 90°, the delay compensation accuracy of the transmission line delay analysis module is ±0.3ps.

[0039] Specifically, this prevents the temperature sensor and frequency detection circuit from malfunctioning due to ambient temperature exceeding the operating range, ensuring the accuracy of compensation inputs such as ΔT and frequency parameters.

[0040] The module achieves a compensation accuracy of ±0.3ps for transmission line delay analysis when the cable is bent at 90°, focusing on the system's performance under extreme physical installation scenarios: 90° is a common extreme bending angle for clock transmission line wiring within equipment (such as cable bends between PCB boards). At this angle, the clock transmission line is prone to additional delay due to structural deformation. The sub-picosecond compensation accuracy of ±0.3ps is superior to traditional solutions (compensation error ≥1ps when bent at 90°). Even under extreme bending conditions, the module can still calculate k_θ. The θ_bend compensation term offsets the phase deviation caused by bending, ensuring the phase consistency of the terminal clock signal.

[0041] In one embodiment of this application, the transmission line delay parsing module is further configured to perform delay predistortion, specifically including: calculating the predicted total clock transmission line delay, wherein the delay prediction formula used is: Based on the predicted total clock transmission line delay, and combined with the material phase temperature coefficient, the delay predistortion is fitted to obtain the amount of predistortion.

[0042] In the formula, β and γ are calibration coefficients, which are obtained through offline calibration by multi-frequency S-parameter sweep at 1GHz and 40GHz. The predicted total clock transmission line delay (in ps) is the basis for subsequent calculations of the predistortion bit (it should be noted that both the predistortion bit and the delay predistortion are distortion errors; one is expressed in phase and the other in time. For continuous waves, these two can be considered equivalent, but for pulse signals, this parameter is different). This represents the inherent delay term of the clock transmission line; c is the length of the clock transmission line (in meters), and c is the speed of light (3 × 10⁻⁶). 8 m / s); It is the square root of the effective dielectric constant that varies with temperature (T) and frequency (f), and reflects the basic propagation delay of the signal under specific material, length, temperature, and frequency (the larger the dielectric constant, the slower the signal propagates and the greater the delay). Indicates temperature-related delay terms; The phase temperature coefficient of the material (unit: ps / ℃) m), reflecting the rate of change of the material phase with temperature; β is the calibration coefficient, quantifying the additional effect of temperature fluctuations on the delay; For bending-related delay terms, The bending angle of the cable (unit: °) is represented by the square term, which reflects the nonlinear effect of bending on delay (the larger the bending angle, the faster the delay increases). γ is a calibration coefficient that adapts to the bending characteristics of different clock transmission line types.

[0043] The multi-GHz clock tree dynamic phase calibration system of this embodiment can be used in a variety of devices, such as phased array radar, millimeter-wave imaging systems, 5G / 6G communication base stations, high-end test and measurement instruments, and quantum computing control systems.

[0044] A phased array radar needs to achieve precise beam pointing through clock synchronization of hundreds of array elements. The multi-GHz clock tree dynamic phase calibration system in this embodiment can compensate for phase deviations caused by temperature changes (-40℃~65℃) and cable vibration and bending in real time, ensuring radar ranging and improving speed measurement accuracy.

[0045] This multi-GHz clock tree dynamic phase calibration system is applied to millimeter-wave imaging systems operating in the 24-40GHz frequency range. In vehicle-mounted millimeter-wave radar and security inspection imaging equipment, the phase consistency of multi-channel clock signals directly affects imaging resolution. By suppressing SMA interface standing waves (traditional solutions have phase jumps ≥1ps, while optimized solutions have ≤0.2ps), the system can improve imaging clarity and reduce false detection rates.

[0046] This multi-GHz clock tree dynamic phase calibration system is applied to 5G / 6G communication base stations with core operating frequencies in the Sub-6GHz and millimeter-wave bands. Massive MIMO base stations require the synchronization of clock signals across dozens of RF channels. The system can compensate for temperature drift (room temperature fluctuations of ±10℃) and impedance changes caused by cable aging during long-term base station operation, ensuring signal transmission delay jitter ≤0.5ps and improving communication rate stability.

[0047] This multi-GHz clock tree dynamic phase calibration system is applied to high-end test and measurement instruments. In devices such as vector network analyzers and signal generators, the phase stability of 1-40GHz high-frequency clocks determines measurement accuracy. Through dynamic calibration, the system can reduce instrument phase measurement errors, meeting the precision testing needs of aerospace and semiconductor fields.

[0048] This multi-GHz clock tree dynamic phase calibration system is applied to quantum computing control systems. Quantum bit manipulation requires nanosecond-level timing synchronization. The system can compensate for the phase shift caused by the temperature difference between the low-temperature environment (4K~300K) and the room temperature region, ensuring that the synchronization accuracy of multi-qubit gate operations is ≤0.1ps, thereby improving the success rate of quantum computing.

[0049] Example 2: This example provides a method for suppressing dynamic phase deviation of a multi-GHz clock tree. This suppression method is applied to the multi-GHz clock tree dynamic phase calibration system in Example 1. The suppression method includes: S1: Acquiring incident and reflected wave signals at the PCB vias and SMA interfaces of the clock transmission line through the distributed directional coupler array; calculating the standing wave ratio (VSWR) and phase distortion based on the amplitude ratio |Γ| of the incident and reflected waves. S2: Determine whether the amplitude ratio |Γ| is greater than a threshold (set to 0.1 in this embodiment). If it is greater than the threshold, drive the adjustable capacitor matching network to dynamically adjust the capacitor value (in this embodiment, the capacitor value is adjusted in steps of 0.1fF) until the amplitude ratio |Γ| ≤ the threshold. S3: Collect the temperature change ΔT through the temperature sensor that detects both phase and frequency, and collect the cable bending angle through the cable bending angle detection unit. It then calls the frequency-to-dielectric-constant mapping table to obtain the dielectric constant parameter corresponding to the current clock frequency f, and sets ΔT, The parameters f and dielectric constant are input into the multivariate delay compensation model of the transmission line delay analysis module to calculate the clock transmission line delay predistortion. S4: The delay predistortion is processed by the transmission line delay analysis module. It is converted into a predistortion control signal and output to the voltage controlled delay line (VCDL), which drives the VCDL to inject a delay predistortion amount into the clock signal between the clock source and the clock transmission line network, thus completing the clock tree phase calibration.

[0050] Specifically, S1: This step is the "data foundation layer" for bias suppression: It uses a distributed directional coupler array to focus on PCB vias and SMA interfaces (previously defined as key nodes prone to impedance mismatch), acquiring amplitude signals and calculating VSWR (Standing Wave Ratio). (Phase distortion) The former is used to determine whether the standing wave exceeds the safety threshold, while the latter quantifies the interference of the standing wave on the phase into specific phase parameters. This provides a basis for the real-time adjustment of S2 and also provides "interference data in the standing wave dimension" for the subsequent multivariate compensation model, avoiding compensation deviations caused by the lack of quantification of the standing wave characteristics.

[0051] When |Γ| < 0.2, Specifically, the impedance mismatch of key nodes in clock transmission lines (PCB vias, SMA interfaces) is mainly "slight mismatch" (|Γ| is usually less than 0.2, corresponding to VSWR < 1.5), and the mismatch characteristics are mainly resistive (the phase effect of the reflection coefficient can be ignored), such as the standing waves caused by installation tolerance and dielectric uniformity deviation in high-frequency clock transmission.

[0052] S2: This step is the "pre-intervention layer" for bias suppression: using VSWR=1.1 as the safe threshold for high-frequency transmission (exceeding this threshold will significantly amplify phase distortion due to impedance mismatch), it triggers an adjustable capacitor matching network to adjust in high-precision steps of 0.1fF. This step precision can accurately match the impedance fine-tuning requirements of multiple GHz bands, avoiding over- or under-adjustment and quickly controlling the standing wave ratio (SWR) within a safe range. The core function of this step is to "solve the most direct SWR interference first," reducing the pressure on subsequent multivariate compensation and ensuring that subsequent compensation calculations only need to handle chronic interferences such as temperature and bending, rather than sudden SWR distortion.

[0053] S3: This step is the "precise calculation layer" for bias suppression: temperature (ΔT) and bending (ΔF) are acquired through a phase and frequency joint detection module. The parameters of frequency (f) and dielectric constant essentially transform three independent interference factors—environmental changes, physical deformation, and signal frequency fluctuations—into quantifiable data that the model can recognize; these are then input into the multivariate delay compensation model for calculation. (Delay predistortion) The core of this method is to integrate multi-dimensional interference into a single, executable compensation index through model algorithms. This ensures that the compensation amount can cover all non-standing wave phase deviations, avoiding the limitations of single-parameter compensation. The calculation formula is as follows: S4: This step is the "final execution layer" of deviation suppression: The transmission line delay parsing module converts Δτ_comp into a voltage control signal that can be recognized by VCDL, and then injects a delay pre-distortion amount between the clock source and the clock transmission line through VCDL. Its logic is reverse cancellation: before the signal enters the clock transmission line, a phase compensation that is opposite in direction and equal in magnitude to the clock transmission line delay deviation is added in advance to ensure that after the signal passes through the clock transmission line, the original deviation is canceled by the pre-distortion and finally the phase is consistent when it reaches the terminal.

[0054] This step transforms the monitoring, adjustment, and calculation results from the previous steps into actual phase calibration actions, completing the monitoring, adjustment, calculation, and calibration.

[0055] The process involves four steps: first, suppressing acute standing wave interference; then, compensating for chronic multi-parameter interference; and finally, performing pre-distortion calibration.

[0056] In summary, the multi-GHz clock tree dynamic phase calibration system and deviation suppression method based on standing wave integrity monitoring in this application embodiment enables a phased array radar to achieve precise beam pointing through sub-picosecond clock synchronization (synchronization deviation ≤0.3psRMS) of hundreds of array elements. The system's compensation accuracy for environmental interference inside the radar cabin is as follows: Temperature compensation: In the full temperature range of -40℃ to 65℃, dynamic phase calibration suppresses the phase deviation caused by temperature from 20ps+ to ≤0.4ps, directly reducing the radar ranging error from ±1.5m to ±0.15m; Cable vibration and bending compensation: For cable bending between array elements at 0°~30° and vibration at 10~200Hz, the phase deviation caused by bending / vibration after compensation is ≤0.25ps (reaching 1.2ps without compensation), helping to improve the velocity measurement accuracy from ±0.5m / s to ±0.05m / s, and ultimately achieving a beam pointing error of ≤0.1°, meeting the requirements for high-precision ranging and velocity measurement.

[0057] In summary, compared with the prior art, the present invention has the following beneficial effects: The multi-GHz clock tree dynamic phase calibration system and deviation suppression method based on standing wave integrity monitoring in the embodiments of the present invention enable the phased array radar to achieve precise beam pointing through sub-picosecond clock synchronization of hundreds of array elements. The system compensates for environmental interference in the radar cabin. Within the full temperature range of -40℃ to 65℃, the phase deviation caused by temperature is suppressed and reduced through dynamic phase calibration, thereby reducing radar ranging error. Cable vibration and bending compensation compensates for phase deviation caused by bending and vibration in scenarios involving cable bending and vibration between array elements, improving velocity measurement accuracy and meeting the requirements for high-precision ranging and velocity measurement.

[0058] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0059] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A multi-GHz clock tree dynamic phase calibration system, characterized in that, The system includes a distributed directional coupler array, an adjustable capacitor matching network, a phase and frequency joint detection module, and a transmission line delay analysis module. The distributed directional coupler array is used to acquire the amplitude ratio of the incident and reflected waves in the clock transmission line and the current clock frequency in real time. When the amplitude ratio is detected to be greater than a threshold, the adjustable capacitor matching network is triggered to start adjustment. The adjustable capacitor matching network is used to dynamically adjust the capacitance value, suppressing impedance mismatch by changing the termination impedance of the clock transmission line. The phase and frequency joint detection module is used to detect changes in ambient temperature, physical deformation parameters of the clock transmission line, and dielectric constant parameters corresponding to the current clock frequency, and transmits the detected data to the transmission line delay analysis module in real time. The transmission line delay analysis module calculates the delay predistortion based on the three data transmitted by the phase and frequency joint detection module and the data acquired by the distributed directional coupler array, and converts the delay predistortion into a predistortion control signal output to the voltage-controlled delay line.

2. The multi-GHz clock tree dynamic phase calibration system as described in claim 1, characterized in that, The voltage-controlled delay line is connected in series between the clock source and the clock transmission line network. It is used to receive the pre-distortion control signal output by the transmission line delay analysis module, and inject a delay pre-distortion amount into the clock signal output by the clock source according to the pre-distortion control signal to compensate for the delay deviation of the clock transmission line network.

3. The multi-GHz clock tree dynamic phase calibration system as described in claim 1, characterized in that, The distributed directional coupler array is embedded in key nodes of the clock transmission line, the key nodes being PCB vias and SMA interfaces; the distributed directional coupler array is a microstrip directional coupler, the sampling frequency of which is consistent with the clock frequency of the clock transmission line, the clock frequency ranging from 1 GHz to 40 GHz.

4. The multi-GHz clock tree dynamic phase calibration system as described in claim 1, characterized in that, The phase and frequency joint detection module is also used to receive compensation input data, which includes transmission line type parameters. The transmission line type includes coplanar waveguides with conductor backing, microstrip lines, and striplines. The compensation input data is used to calculate the dielectric constant parameter corresponding to the current clock frequency.

5. The multi-GHz clock tree dynamic phase calibration system as described in any one of claims 1 to 4, characterized in that, The calculation of delay predistortion based on the three data transmitted by the phase and frequency joint detection module and the data acquired by the distributed directional coupler array includes: in, To delay the predistortion amount, This is the temperature compensation coefficient. The accuracy is 0.1 ps / ℃. For frequency compensation coefficients, The bending compensation coefficient is... As the reference frequency, The current clock frequency, The bending angle of the clock transmission line cable.

6. The multi-GHz clock tree dynamic phase calibration system as described in any one of claims 1 to 4, characterized in that, The transmission line delay analysis module is also used to calculate the pre-distortion bit and convert the pre-distortion bit into a control signal output. The process of calculating the pre-distortion bit includes: calculating the predicted total clock transmission line delay; and, based on the predicted total clock transmission line delay and the material phase temperature coefficient, fitting the pre-distortion amount. The formula for calculating the predicted total clock transmission line delay is as follows: In the formula, This represents the predicted total clock transmission line delay; β and γ are calibration coefficients. The phase temperature coefficient of the material; This represents the inherent delay term of the clock transmission line; Where c is the length of the clock transmission line and c is the speed of light; It is the square root of the effective dielectric constant that varies with temperature and frequency, and it reflects the basic transmission delay of a signal under specific materials, lengths, temperatures, and frequencies. The phase temperature coefficient of the material; This refers to the cable bending angle.

7. A method for suppressing dynamic phase deviation in multi-GHz clock trees, characterized in that, The multi-GHz clock tree dynamic phase deviation suppression method is applied to the multi-GHz clock tree dynamic phase calibration system as described in any one of claims 1 to 6. The multi-GHz clock tree dynamic phase deviation suppression method includes the following steps: acquiring incident and reflected wave signals at the PCB vias and SMA interfaces of the clock transmission line through the distributed directional coupler array; and calculating the phase distortion based on the amplitude ratio |Γ| of the incident and reflected waves. The system determines whether the amplitude ratio |Γ| is greater than a threshold value. If it is, it drives the adjustable capacitor matching network to dynamically adjust the capacitor value until the amplitude ratio |Γ| is less than or equal to the threshold value. The temperature change ΔT is collected by the temperature sensor that uses both phase and frequency detection, and the cable bending angle is collected by the cable bending angle detection unit. It then calls the frequency-to-dielectric-constant mapping table to obtain the dielectric constant parameter corresponding to the current clock frequency f, and sets ΔT, The parameters f and dielectric constant are input into the multivariate delay compensation model of the transmission line delay analysis module to calculate the clock transmission line delay predistortion. The delay predistortion is determined by the transmission line delay analysis module. It is converted into a predistortion control signal and output to the voltage control delay line, which drives the voltage control delay line to inject a delay predistortion amount into the clock signal between the clock source and the clock transmission line network, thereby completing the clock tree phase calibration.

8. The multi-GHz clock tree dynamic phase deviation suppression method as described in claim 7, characterized in that, The threshold value for the amplitude ratio is 0.1, and the adjustable capacitor matching network adjusts the capacitor value in steps of 0.1fF.

9. The multi-GHz clock tree dynamic phase deviation suppression method as described in claim 7, characterized in that, The phase distortion Calculation formula include: 。 10. The multi-GHz clock tree dynamic phase deviation suppression method as described in claim 7, characterized in that, The calculated clock transmission line delay predistortion ,include: in, To delay the predistortion amount, This is the temperature compensation coefficient. The accuracy is 0.1 ps / ℃. For frequency compensation coefficients, The bending compensation coefficient is... As the reference frequency, The current clock frequency, The bending angle of the clock transmission line cable.

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