Dynamic terminal resistance system and adjusting method
By adjusting the resistance value in real time through a dynamic terminating resistor system, the problem of impedance mismatch of fixed resistors in the complex automotive environment is solved, thereby achieving signal quality stability and communication system reliability, and preventing secondary interference during faults.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-27
- Publication Date
- 2026-03-10
AI Technical Summary
In the existing technology, fixed-value terminating resistors are difficult to adapt to temperature drift and communication mode switching in the complex environment of automobiles, which leads to changes in signal frequency, a decrease in signal integrity, and even communication failures, affecting driving safety.
A dynamic terminating resistor system is adopted, which uses variable resistor elements, data acquisition modules, adjustment modules and control modules to sense environmental parameters in real time, dynamically adjust the resistance value to match the optimal impedance, and combine with the protection module to suppress the influence of environmental factors, so as to achieve closed-loop control and self-optimization.
It effectively suppresses signal reflection and oscillation, maintains the stability and reliability of the communication system, ensures optimal impedance matching under various operating conditions, improves communication quality and system robustness, prevents immediate shutdown in case of hardware failure, and avoids interference with the vehicle network.
Smart Images
Figure CN121634979A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of automotive electronic communication, and specifically to a dynamic terminating resistor system and its adjustment method. Background Technology
[0002] With the rapid development of automotive intelligence, connectivity, and electrification, the in-vehicle electronic and electrical architecture is becoming increasingly complex, and the number of electronic control units (ECUs) is increasing daily. Controller Area Networks (CAN), Local Interconnect Networks (LIN), and other communication buses serve as the nerve center of the in-vehicle network. The integrity and reliability of their signal transmission directly affect the functional safety and performance of the entire vehicle. In bus communication systems, terminating resistors are key components for ensuring signal quality. Their core function is to match the characteristic impedance of the communication cable to eliminate reflections, oscillations, and ringing caused by impedance discontinuities at the end of the transmission line, thereby ensuring signal clarity and stability.
[0003] Currently, the industry commonly uses fixed-value terminating resistors (such as the standard 120Ω resistor in the CAN bus). This solution is simple to design and low in cost, and can meet basic requirements under ideal operating conditions. However, in the complex and ever-changing automotive environment, due to the wide temperature range of automotive operating environments (-40℃ to above 125℃), accompanied by vibration, high humidity, and complex electromagnetic interference, the resistance value of fixed resistors will drift with temperature. Their packaging materials may also deteriorate in humid and hot environments, causing the actual impedance matching effect to deviate from the design optimum. Furthermore, with the upgrading of in-vehicle networks, support for multi-rate communication (such as from classic CAN to CANFD) has become standard. The signal frequency components at different communication rates differ greatly, which puts forward different optimal requirements for the impedance value of the terminating resistor. Fixed resistors are difficult to respond to the signal frequency changes caused by communication mode switching, resulting in mismatch in high-rate modes and a serious decrease in signal integrity. This not only reduces communication quality, but may even cause communication failures in extreme cases, posing a hidden danger to driving safety. Therefore, there is an urgent need in this field for an intelligent terminating resistor solution that can adapt to changes in environment and operating conditions and dynamically adjust its own resistance value to always maintain the optimal impedance matching state to solve the above-mentioned defects. Summary of the Invention
[0004] This application provides a method and system for adjusting a dynamic terminating resistor to address the aforementioned technical deficiencies.
[0005] In a first aspect, embodiments of this application provide a dynamic terminating resistor system, comprising: A terminating resistor module, which includes a variable resistive element; The data acquisition module, which is installed on the terminating resistor module, is used to acquire the status parameters of the terminating resistor module and the equivalent electrical length of the communication bus of the terminating resistor module. An adjustment module, which is electrically connected to the terminating resistor module, is used to adjust the resistance value of the terminating resistor module. The control module, which is communicatively connected to the data acquisition module and the adjustment module, is configured to determine the adaptive resistance value of the terminating resistance module based on the acquired state parameters and equivalent electrical length, and control the adjustment module to make adjustments.
[0006] In conjunction with the first aspect, in one implementation, it further includes: A protection module, disposed on the variable resistor element, is configured to physically encapsulate and protect the variable resistor element to suppress resistance drift of the terminating resistor module caused by environmental factors.
[0007] Secondly, embodiments of this application provide an adjustment method based on a dynamic terminating resistor system, comprising the following steps: The status parameters of the terminating resistor module and the equivalent electrical length of the communication bus are obtained. The status parameters include temperature data, humidity data, electromagnetic interference intensity data, and signal frequency data. Based on the acquired state parameters and equivalent electrical length, the adaptive resistance value of the terminal resistance module is calculated using a preset algorithm, and the resistance of the terminal resistance module is adjusted by the control and adjustment module based on the adaptive resistance value. Monitor the signal quality of the communication bus after adjustment. When the signal quality does not meet the preset standard, adjust the control parameters for calculating the adapter resistance value of the terminal resistor module, and recalculate the adapter resistance value of the terminal resistor module and adjust the resistance of the terminal resistor module until the preset standard is met.
[0008] In conjunction with the second aspect, in one implementation, the step of calculating the adaptation resistance value of the terminating resistance module based on the acquired state parameters and equivalent electrical length using a preset algorithm specifically includes: The base resistance value is determined based on the equivalent electrical length and signal frequency data through a preset mapping relationship; Based on the temperature data, humidity data, and electromagnetic interference intensity data, as well as the deviations relative to their respective reference values, the state parameter compensation coefficient is calculated. The adaptation resistance value is calculated based on the base resistance value and the state parameter compensation coefficient.
[0009] In conjunction with the second aspect, in one embodiment, before calculating the adaptation resistance value of the terminating resistor module, a preprocessing step for the state parameters is further included, the preprocessing step comprising: Outlier values are removed from the state parameters; The state parameters are filtered and denoised.
[0010] In conjunction with the second aspect, in one implementation, the adjustment of the resistance of the terminal resistance module based on the adaptive resistance value control module is achieved by a proportional-integral controller using a closed-loop control method.
[0011] In conjunction with the second aspect, in one embodiment, the signal quality of the communication bus includes: return loss data, differential mode amplitude data, signal rise time data, eye diagram height data, eye diagram width data, and frame error rate data.
[0012] In conjunction with the second aspect, in one implementation, the preset standard includes: The return loss data is greater than or equal to the first preset value; The differential mode amplitude value is greater than or equal to the second preset value and less than or equal to the third preset value; The signal rise time data is less than or equal to the fourth preset value; Eye height data is greater than or equal to the fifth preset value; The eye diagram width data is greater than or equal to the product of its bit time and a preset scaling factor; The frame error rate is less than the sixth preset value.
[0013] In conjunction with the second aspect, in one embodiment, the control parameters for adjusting the adaptation resistance value of the calculation terminal resistance module include: Based on the first preset step size, adjust the proportional gain coefficient of the proportional-integral controller; The integration time constant is adjusted based on the second preset step size; The resistance adjustment step size of the variable resistor element is adjusted based on the third preset step size; Adjust any one of the filtering time constants in the preprocessing step based on the fourth preset step size.
[0014] In conjunction with the second aspect, in one embodiment, the monitoring of the signal quality of the adjusted communication bus also includes a system status assessment step, which includes: The system acquires the operating status data of the dynamic terminating resistor system. The operating status data includes the power supply voltage data of the terminating resistor module, the temperature data of the terminating resistor module, the tap position of the variable resistor element, the online status of the sensor used to acquire the temperature data, humidity data, and electromagnetic interference intensity data of the terminating resistor module, and the number of watchdog resets. If any item in the running status data does not meet its corresponding safety threshold range, the system is judged to be unhealthy, and the system is immediately shut down and a system fault is reported.
[0015] The beneficial effects of the technical solutions provided in this application include: 1. By sensing multi-dimensional parameters such as signal frequency, temperature, humidity, and electromagnetic interference intensity in real time, and combining them with the equivalent electrical length of the communication bus, the resistance value of the terminating resistor module is dynamically calculated and adjusted, achieving a leap from static matching to dynamic adaptation. This method fundamentally solves the impedance mismatch problem of fixed resistors caused by communication mode switching and environmental factors. It can not only effectively suppress signal reflection and oscillation, ensuring that key indicators such as return loss and eye diagram height / width remain excellent, but also ensure that the terminating resistor module can maintain the optimal impedance matching state under various operating conditions, thereby significantly improving the stability and reliability of the communication system.
[0016] 2. By monitoring and adjusting the signal quality of the communication bus after adjustment, and adjusting the control parameters of the adaptive resistance value of the calculation terminal resistance module and re-executing the resistance value calculation and output when the quality is not up to standard, the dynamic terminal resistance system is endowed with the ability to self-optimize online. It can actively compensate for the performance degradation caused by component manufacturing tolerances, long-term aging and unmodeled interference, and ensure the high accuracy and strong robustness of the system throughout its entire life cycle.
[0017] 3. By detecting the operating status data of the adjusted dynamic terminating resistor system, this method can promptly identify underlying hardware faults or extreme operating conditions that cannot be repaired by parameter adjustment (such as resistor overheating, power supply abnormality, and depletion of adjustment capability). Once such a fault is detected, the method will immediately stop the system and report the fault, thereby preventing the system from adjusting the resistance value when it has its own fault, avoiding secondary interference or damage to the vehicle communication network, and enhancing the reliability of the system and the security of the vehicle network. Attached Figure Description
[0018] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0019] Figure 1 This is a schematic diagram of the terminating resistor system of the present invention; Figure 2 This is a schematic diagram of the main steps of the adjustment method of the present invention; Figure 3 This is a flowchart of the adjustment method of the present invention. Detailed Implementation
[0020] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present application.
[0021] Example 1: Please refer to the figure. This application provides a dynamic terminating resistor system, including: A terminating resistor module, which includes a variable resistive element; The variable resistor element can be a digital potentiometer, which is connected between the CAN_H and CAN_L buses as a terminating resistor, or it can be a variable resistor circuit composed of a MOSFET switch array and a high-precision thin-film resistor network. This circuit controls the on and off of multiple MOSFETs to combine precision resistors of different resistance values in series and parallel to synthesize the target resistance value.
[0022] The data acquisition module, which is installed on the terminating resistor module, is used to acquire the status parameters of the terminating resistor module and the equivalent electrical length of the communication bus of the terminating resistor module. Specifically, it includes: The temperature acquisition unit, preferably a temperature sensor, is attached to the inner surface of the housing of the terminating resistor module or the surface of the variable resistor element, and is used to directly measure the temperature data of the terminating resistor module. A humidity acquisition unit, preferably a humidity sensor, is disposed inside the housing of the terminating resistor module and is used to measure humidity data inside the housing; An electromagnetic interference intensity acquisition unit, preferably an electromagnetic interference sensor, is mounted on the circuit board of the terminating resistor module and is used to monitor electromagnetic interference intensity data in the environment. The signal frequency acquisition unit is connected to the controller of the communication bus and is used to acquire the current signal frequency data by reading the registers of the bus controller or parsing the bus waveform. An adjustment module, which is electrically connected to the terminating resistor module, is used to adjust the resistance value of the terminating resistor module. Specifically, its implementation method corresponds to the type of variable resistor element selected: When the variable resistor element is a digital potentiometer, the adjustment module is a digital interface driver circuit. This circuit is connected to the general-purpose input / output pins of the control module and is configured to convert the digital commands issued by the control module into electrical signals that conform to a specific communication protocol (such as SPI, I²C) and drive the digital potentiometer to change the state of its internal analog switch, thereby precisely adjusting its resistance value. When the variable resistor element is a MOSFET array and a resistor network, the adjustment module is an analog drive circuit. This circuit receives the analog voltage signal output from the digital-to-analog converter of the control module and converts the voltage signal into a drive signal that can quickly and reliably control the MOSFET gate to turn on and off, thereby switching the combination of precision resistors to synthesize the target resistance value. The control module, which is communicatively connected to the data acquisition module and the adjustment module, is configured to determine the adaptive resistance value of the terminating resistance module based on the acquired state parameters and equivalent electrical length, and control the adjustment module to make adjustments. The control module can be implemented as a standalone microcontroller. This microcontroller connects to the data acquisition module and the adjustment module through its built-in peripherals such as ADC, DAC, SPI / I²C, and executes a pre-defined resistance adjustment program. Alternatively, it can be integrated into the vehicle's existing high-performance electronic control unit, such as the body domain controller or gateway controller. In this configuration, the data acquisition module and the adjustment module are directly connected to the domain controller, which executes the resistance adjustment program by running the corresponding software program.
[0023] A protection module, located on the variable resistor element, is configured to physically encapsulate and protect the variable resistor element. Specifically: The protection module uses an inert medium as the encapsulation material, preferably addition-cured low-stress silicone or high thermal conductivity epoxy resin. This material is chemically stable in a temperature range of -55°C to 150°C and a relative humidity range of 0% to 100%, and its dielectric constant changes by less than 2%. It adopts a coating protection method, forming a uniform insulating coating of 50-80µm thickness on the surface of the variable resistor element through a precision coating process. Alternatively, it can adopt a potting protection method, encapsulating the variable resistor element entirely in an epoxy resin potting layer to form an integrated protection structure. This protection module can effectively isolate water vapor, oxygen, and ionic contaminants, and suppress the resistance drift of the terminal resistor module caused by environmental factors.
[0024] Example 2: Please see Figure 2 and Figure 3 Based on the same technical concept as Embodiment 1, Embodiment 2 of this application provides a method for adjusting a dynamic terminating resistor system, including the following steps: S1. Obtain the status parameters of the terminating resistor module and the equivalent electrical length of the communication bus. The status parameters include temperature data, humidity data, electromagnetic interference intensity data, and signal frequency data. The equivalent electrical length of the communication bus is a fixed configuration parameter that is pre-stored in the non-volatile memory of the control module. This parameter is determined and written according to the vehicle model's communication bus design during vehicle manufacturing. When this step is executed, the control module directly reads the preset equivalent electrical length value from its storage unit. Status parameters are obtained through the data acquisition module.
[0025] S2. Based on the acquired state parameters and equivalent electrical length, calculate the adaptation resistance value of the terminal resistor module using a preset algorithm, and adjust the resistance of the terminal resistor module based on the adaptation resistance value. S201, Data Preprocessing: Before performing the calculation in step S2, in order to ensure the reliability of the data and the stability of the algorithm, the raw state parameters transmitted from the data acquisition module need to be preprocessed. The preprocessing includes the following steps: Outlier removal: The 3σ Laida criterion is applied to the sampled temperature data, humidity data, electromagnetic interference intensity data and signal frequency data. If the data of three consecutive sampling periods exceeds the range of ±3 times the standard deviation of its recent data mean, it is judged as an outlier and replaced with the value of the previous valid period. Data filtering: Electromagnetic interference intensity data and signal frequency data are filtered by a 5-point moving average; temperature data and humidity data are filtered by a first-order infinite impulse response low-pass filter, with the software-implemented cutoff frequency set to 0.5 Hz.
[0026] S202, Calculation of adapter resistor value: ① The base resistance value is determined based on the equivalent electrical length and signal frequency data through a preset mapping relationship; The control module determines the base resistance value based on the equivalent electrical length of the communication bus and the pre-processed signal frequency data by querying a preset mapping relationship. This mapping relationship is pre-stored in the control module's non-volatile memory in the form of a two-dimensional lookup table. This mapping table establishes the correspondence between signal frequency data, equivalent electrical length, and base resistance value. As an example, the table below shows a portion of the mapping relationship:
[0027] It is important to note that the mapping table is pre-calibrated using a vector network analyzer and covers an expected frequency and length operating range. The table above shows a partial example of this mapping table. For parameter pairs not directly defined in the mapping table, the control module is configured to process them to output a reasonable base resistance value, for example, through an extrapolation algorithm or by limiting it to the closest boundary value within the mapping table, thereby ensuring stable operation of the system across the entire operating range. ② Calculate the state parameter compensation coefficient based on temperature data, humidity data, electromagnetic interference intensity data, and their deviations from their respective reference values. ; State parameter compensation coefficient The calculation is performed using preprocessed temperature, humidity, and electromagnetic interference intensity data, specifically using the following formula: ; in, The temperature data is after preprocessing and is expressed in degrees Celsius (°C). The preset reference value for temperature data is a reference temperature calibrated under a standard laboratory environment (e.g., 25°C), which is preferably 25°C in this embodiment; The sensitivity coefficient for temperature data is expressed in ohms per degree Celsius (Ω / ℃). Its physical meaning is the typical change in the terminal resistor module caused by each 1℃ deviation of the temperature data from the preset reference value. Its value is obtained by performing gradient tests and fitting in the temperature chamber. The humidity data is after preprocessing, and the unit is relative humidity %RH; The preset reference value for humidity data is preferably 50%RH in this embodiment, which is also obtained through calibration; The sensitivity coefficient for humidity data is expressed in ohms per percentage relative humidity (Ω / %RH), and its value is obtained by performing gradient tests and fitting in a humidity chamber. The data represents the electromagnetic interference intensity after data preprocessing, in decibels and microvolts (dBμV). The preset reference value for electromagnetic interference intensity is preferably 60 dBμV in this embodiment; The sensitivity coefficient for electromagnetic interference intensity data is expressed in ohms per dB / μV. Its value is obtained by performing gradient tests and fitting in a TEM chamber. Preset baseline value ( , , ) and sensitivity coefficient ( , , All of these are used as calibration parameters and are pre-stored in the non-volatile memory of the control module; ③ Calculate the adaptation resistance value based on the basic resistance value and the state parameter compensation coefficient.
[0028] The adapter resistor value is calculated using the following formula: ; in, To determine the base resistance value through a preset mapping relationship.
[0029] S203, resistance adjustment; After calculating the matching resistor value Then, the control module sends corresponding instructions to the adjustment module, which is configured to use a closed-loop control method to precisely adjust the resistance value of the terminal resistor module (i.e., the variable resistor element) to the appropriate resistance value. Specifically, this closed-loop control is implemented through a proportional-integral controller, and its workflow is as follows: Command issued: The control module will adapt the resistance value. Send to the adjustment module; Drive and Execution: The adjustment module drives the variable resistor element to begin adjustment according to this instruction; Real-time sampling: At the same time, the control module samples the voltage or current signal across the variable resistor element in real time through its internal high-precision analog-to-digital converter; Resistance conversion and comparison: Convert the sampled signal into the current actual resistance value. And continuously calculate and adapt the resistor value. Error between ; PID control: The proportional-integral controller adjusts based on this error. and its integral, and based on its current proportional gain coefficient. With integration time constant The control signal output to the regulation module is adjusted in real time and dynamically. Through the aforementioned closed-loop feedback mechanism, the system forces the actual resistance value of the terminating resistor module to be... It quickly and smoothly approaches and eventually locks onto the matching resistor value. The steady-state error is maintained until it is less than a preset tolerance, which is preferably 0.5 Ω in this embodiment.
[0030] S3. Monitor the signal quality of the communication bus after adjustment. When the signal quality does not meet the preset standard, adjust the control parameters of the adaptive resistance value of the terminal resistor module, and recalculate the adaptive resistance value of the terminal resistor module and adjust the resistance of the terminal resistor module until the preset standard is met.
[0031] S301, Signal Monitoring; Based on the adaptation resistor value calculated in step S2, the control module sends a command to the adjustment module, thereby adjusting the resistance value of the terminal resistor module to the adaptation resistor value. To ensure the stability of the system after adjustment, the control module continuously or periodically monitors the physical layer signals of the communication bus through a bus transceiver or a dedicated signal integrity analysis circuit. These signals mainly include: return loss data, differential mode amplitude data, signal rise time data, eye diagram height data, eye diagram width data, and frame error rate data. The control module compares the monitored signal quality indicators with the qualified thresholds stored in the memory. If all indicators meet the preset standards, the current resistance value and all control parameters are maintained and continuously monitored. If any indicator does not meet the preset standards, it is determined that the current resistance value setting effect is not good, and the parameter self-calibration process is triggered.
[0032] In one specific example of this embodiment, the preset standards are shown in the table below:
[0033] The control module monitors and acquires signal quality assessment data of the communication bus in real time through its connected hardware resources and internal firmware algorithms. Those skilled in the art should understand that the following implementation is an example of this embodiment, and any technical means that can achieve the same or equivalent function falls within the protection scope of this invention. Specifically: Return loss data: The control module estimates or directly obtains parameter values related to return loss through its internal or connected dedicated impedance detection circuit, or by analyzing the built-in diagnostic information provided by the bus transceiver chip. Differential mode amplitude data: The control module synchronously samples the CANH and CANL signals through its high-precision analog-to-digital converter, and calculates the voltage difference between the two in real time in the firmware to obtain the differential mode amplitude value; Signal rise time data: The control module captures the bus signal edge at a high sampling rate through its ADC, and calculates the time required for the signal amplitude to rise from 20% to 80% in the firmware through an algorithm, thus obtaining the signal rise time; Eye diagram height and width data: The control module implements software eye diagram analysis in the firmware. It continuously samples the bus signal for a period of time (e.g., 1000 bit cycles), superimposes and aligns the waveforms of each bit cycle on the time axis, and automatically calculates the eye diagram opening in the vertical direction (eye diagram height) and the horizontal direction (eye diagram width) through an algorithm. The number of superimposed bit cycles can be adjusted according to processing power and accuracy requirements.
[0034] Error frame rate data: The control module directly reads the error count register and the received frame counter of the bus controller (such as the CAN controller) to count the error frame rate within a unit of time. The unit of time for counting can be configured according to monitoring requirements.
[0035] It should be noted that the above qualified thresholds are only specific numerical examples used in this embodiment. In actual applications, they can be adjusted according to different bus specifications, vehicle configurations, or performance requirements.
[0036] S302, Self-calibration process; If any data in step S301 fails to meet the qualified threshold in the preset standard, the control module will automatically trigger the self-calibration process, as follows: The control parameters to be adjusted include: the proportional gain coefficient of the proportional-integral controller. Integral time constant The resistance adjustment step size of the variable resistor element Filtering time constant in the data preprocessing step In a specific example of this embodiment, the initial values of each parameter and their adjustment strategies are shown in the table below:
[0037] To ensure system stability and prevent oscillations during adjustment, the self-calibration process adjusts only one parameter in the table above in each iteration.
[0038] S303, System Monitoring; After the resistance value adjustment is completed, or during its normal operation, the dynamic terminating resistor model also needs to monitor the status of the dynamic terminating resistor system to ensure its long-term reliability and safety. Specifically, the control module periodically acquires and evaluates the operating status data of the dynamic terminating resistor system itself. The operating status data includes, but is not limited to: the power supply voltage data of the terminating resistor module, the temperature data of the terminating resistor module, the tap position of the variable resistor element, the online status of the sensors used to acquire the temperature data, humidity data, and electromagnetic interference intensity data of the terminating resistor module, and the number of watchdog resets.
[0039] The control module compares the above parameters with a pre-stored safety threshold range. When any status parameter exceeds its safety threshold, the system is configured to immediately take the highest priority fault handling measures. In a specific example of this embodiment, the safety threshold is as follows:
[0040] If the system status monitoring detects a serious anomaly (such as power supply exceeding limits, excessive temperature, or tap position saturation), the system determines that it is in an unhealthy state and immediately and unconditionally stops the resistance adjustment function. At the same time, it immediately shuts down and reports the system fault, thereby preventing the system from adjusting the resistance value when it has a fault, avoiding secondary interference or damage to the vehicle communication network, and enhancing the reliability of the system and the security of the vehicle network.
[0041] It should be noted that the above safety threshold range is only a specific numerical example used in this embodiment. In actual applications, it can be adjusted according to different bus specifications, vehicle configurations, or performance requirements.
[0042] Example 3: This embodiment also provides a software system integrated into a control module for executing the adjustment method of the dynamic terminating resistor system as described in Embodiment 2, which specifically includes: Data preprocessing unit: It is configured to perform the data preprocessing steps in Embodiment 2, including outlier removal and filtering noise reduction of the raw sensor data; Target resistance calculation unit: It is configured to perform the calculation steps in Embodiment 2, including obtaining the basic resistance value based on the equivalent electrical length and signal frequency by looking up a table, calculating the compensation coefficient based on environmental parameters, and finally synthesizing the adaptation resistance value; Closed-loop control unit: It is configured to execute the adjustment steps in Embodiment 2, generate control signals through a proportional-integral controller, and drive the adjustment module to achieve precise adjustment of the resistance value; Quality assessment unit: It is configured to perform the signal monitoring step in method embodiment two, analyze the bus signal in real time, and acquire quality indicators including return loss data, differential mode amplitude data, signal rise time data, eye diagram height data, eye diagram width data, and frame error rate data; Parameter self-calibration unit: It is configured to perform the self-calibration process in Embodiment 2, and automatically adjust the proportional gain coefficient when the signal quality is substandard. Integral time constant The resistance adjustment step size of the variable resistor element Filtering time constant in the data preprocessing step Including control parameters; System Status Management Unit: It is configured to perform the system monitoring steps in Embodiment 2, monitor the system health status, and trigger the fault safety process in case of an anomaly.
[0043] It should be understood that the above division of software functional units is only logical and is used to clearly describe the functions they perform. In actual implementation, they can be merged or split. It should be noted that the initial values and adjustment steps of the parameters mentioned above are the specific configurations adopted in this embodiment. In practical applications, these initial values and adjustment steps pre-stored in the control module can be calibrated and optimized according to different system designs or vehicle configurations. In the description of this application, it should be noted that the terms "upper," "lower," etc., indicating orientation or positional relationships are based on the orientation or positional relationships shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application. Unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linkage" should be interpreted broadly. For example, they can be fixed connections, detachable connections, or integral connections; they can be mechanical connections or electrical connections; they can be direct connections or indirect connections through an intermediate medium; and they can be internal connections between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.
[0044] It should be noted that in this application, relational terms such as "first" and "second" are used merely 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.
[0045] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.
Claims
1. A dynamic termination resistance system, characterized by, The application relates to a terminal resistance module, comprising: a terminal resistance module comprising a variable resistance element; a data acquisition module arranged on the terminal resistance module, used for acquiring a state parameter of the terminal resistance module and an equivalent electrical length of a communication bus of the terminal resistance module; an adjusting module electrically connected with the terminal resistance module, used for adjusting the resistance value of the terminal resistance module; a control module in communication connection with the data acquisition module and the adjusting module, configured to determine an adaptive resistance value of the terminal resistance module based on the acquired state parameter and the equivalent electrical length, and control the adjusting module to adjust.
2. The dynamic termination resistance system of claim 1, wherein, Further comprising: a protection module arranged on the variable resistance element, configured to physically encapsulate and protect the variable resistance element, so as to inhibit the resistance value drift of the terminal resistance module caused by environmental factors.
3. A method of regulating a dynamic termination resistance system as claimed in claim 1, characterized in that, The application further comprises the following steps: acquiring a state parameter of the terminal resistance module and an equivalent electrical length of the communication bus, wherein the state parameter comprises temperature data, humidity data, electromagnetic interference intensity data and signal frequency data; calculating an adaptive resistance value of the terminal resistance module based on the acquired state parameter and the equivalent electrical length through a preset algorithm, and controlling the adjusting module to adjust the resistance of the terminal resistance module based on the adaptive resistance value; monitoring the signal quality of the adjusted communication bus, and when the signal quality does not meet a preset standard, adjusting the control parameter for calculating the adaptive resistance value of the terminal resistance module, and recalculating the adaptive resistance value of the terminal resistance module and adjusting the resistance of the terminal resistance module until the preset standard is met.
4. The method of adjusting a dynamic termination resistance system of claim 3, wherein, The application further comprises the following steps: calculating an adaptive resistance value of the terminal resistance module based on the acquired state parameter and the equivalent electrical length through a preset algorithm, and controlling the adjusting module to adjust the resistance of the terminal resistance module based on the adaptive resistance value; monitoring the signal quality of the adjusted communication bus, and when the signal quality does not meet a preset standard, adjusting the control parameter for calculating the adaptive resistance value of the terminal resistance module, and recalculating the adaptive resistance value of the terminal resistance module and adjusting the resistance of the terminal resistance module until the preset standard is met. The application further comprises the following steps:
5. The method of adjusting a dynamic termination resistance system of claim 3, wherein, calculating an adaptive resistance value of the terminal resistance module based on the acquired state parameter and the equivalent electrical length through a preset algorithm, and controlling the adjusting module to adjust the resistance of the terminal resistance module based on the adaptive resistance value; monitoring the signal quality of the adjusted communication bus, and when the signal quality does not meet a preset standard, adjusting the control parameter for calculating the adaptive resistance value of the terminal resistance module, and recalculating the adaptive resistance value of the terminal resistance module and adjusting the resistance of the terminal resistance module until the preset standard is met. The application further comprises the following steps:
6. The method of adjusting a dynamic termination resistance system of claim 5, wherein, calculating an adaptive resistance value of the terminal resistance module based on the acquired state parameter and the equivalent electrical length through a preset algorithm, and controlling the adjusting module to adjust the resistance of the terminal resistance module based on the adaptive resistance value; 7. The method of claim 3, wherein the dynamic termination resistance system is adjusted by, monitoring the signal quality of the adjusted communication bus, and when the signal quality does not meet a preset standard, adjusting the control parameter for calculating the adaptive resistance value of the terminal resistance module, and recalculating the adaptive resistance value of the terminal resistance module and adjusting the resistance of the terminal resistance module until the preset standard is met.
8. The method of claim 3, wherein, The application further comprises the following steps: calculating an adaptive resistance value of the terminal resistance module based on the acquired state parameter and the equivalent electrical length through a preset algorithm, and controlling the adjusting module to adjust the resistance of the terminal resistance module based on the adaptive resistance value; monitoring the signal quality of the adjusted communication bus, and when the signal quality does not meet a preset standard, adjusting the control parameter for calculating the adaptive resistance value of the terminal resistance module, and recalculating the adaptive resistance value of the terminal resistance module and adjusting the resistance of the terminal resistance module until the preset standard is met. The application further comprises the following steps: calculating an adaptive resistance value of the terminal resistance module based on the acquired state parameter and the equivalent electrical length through a preset algorithm, and controlling the adjusting module to adjust the resistance of the terminal resistance module based on the adaptive resistance value; monitoring the signal quality of the adjusted communication bus, and when the signal quality does not meet a preset standard, adjusting the control parameter for calculating the adaptive resistance value of the terminal resistance module, and recalculating the adaptive resistance value of the terminal resistance module and adjusting the resistance of the terminal resistance module until the preset standard is met. The application further comprises the following steps:
9. The method of claim 6, wherein, calculating an adaptive resistance value of the terminal resistance module based on the acquired state parameter and the equivalent electrical length through a preset algorithm, and controlling the adjusting module to adjust the resistance of the terminal resistance module based on the adaptive resistance value; monitoring the signal quality of the adjusted communication bus, and when the signal quality does not meet a preset standard, adjusting the control parameter for calculating the adaptive resistance value of the terminal resistance module, and recalculating the adaptive resistance value of the terminal resistance module and adjusting the resistance of the terminal resistance module until the preset standard is met. Adjusting the resistance adjustment step length of the variable resistance element based on a third preset step length; Adjusting any one of the filter time constants in the preprocessing step based on a fourth preset step length.
10. The method of claim 3, wherein, The monitoring of the signal quality of the adjusted communication bus also includes a system state evaluation step, which includes: Obtaining the running state data of the dynamic terminal resistance system, including the power supply voltage data of the terminal resistance module, the temperature data of the terminal resistance module, the tap position of the variable resistance element, the online state of the sensor for obtaining the temperature data, humidity data, and electromagnetic interference intensity data of the terminal resistance module, and the number of watchdog resets; When any one of the running state data does not meet the corresponding safety threshold range, it is judged that the system state is unhealthy, and the system is immediately shut down while reporting system failure.