Dynamic composite radio frequency immunity test method and system for 5g vehicle-to-everything terminal

Abstract

The application discloses a kind of dynamic composite radio frequency immunity test methods and systems for 5G vehicle networking terminal, belong to electromagnetic compatibility test and vehicle networking communication technical field.For the problem that traditional radio frequency immunity test is static single, cannot reproduce real dynamic composite electromagnetic environment of vehicle, and the authenticity and pertinence of test are insufficient, the present application is positioned terminal sensitive frequency point and critical interference field intensity by stepping frequency pre-detection;For each sensitive frequency point, match corresponding modulation mode, configure three kinds of dynamic field intensity control functions of sinusoidal periodic fluctuation, step mutation, lognormal fading;Dynamic composite radio frequency interference is generated by multi-channel non-coherent synthesis and applied to the terminal to be tested, finally, the degradation and interference margin are quantitatively calculated by combining the non-interference performance benchmark value.The present application greatly improves the test working condition fitting degree and test efficiency, can locate interference short board, and is suitable for 5G vehicle networking terminal electromagnetic compatibility performance test and optimization.

Description

Technical Field

[0001] This invention belongs to the field of electromagnetic compatibility testing and vehicle-to-everything (V2X) communication technology, specifically relating to a dynamic composite radio frequency immunity testing method and system for 5G V2X terminals. Background Technology

[0002] With the rapid development of the intelligent connected vehicle industry, 5G vehicle-to-everything (5G-V2X) technology has become the support for realizing vehicle-road cooperation, high-level autonomous driving, and intelligent transportation. Vehicle communication terminals (including vehicle T-BOX, V2X on-board units (OBU), vehicle gateways, 5G communication modules, etc.) serve as the core carrier for data interaction between vehicles and the outside world, undertaking key functions such as vehicle status reporting, traffic information dissemination, and transmission of vehicle-to-vehicle / vehicle-road cooperative control commands. The stability and reliability of their communication performance directly affect driving safety and the continuous operation of intelligent connected services.

[0003] The actual operating environment of vehicle-mounted communication terminals is a highly complex dynamic electromagnetic environment. On the one hand, there are numerous interference sources with a wide spectrum distribution. Multiple sources of interference exist simultaneously, including adjacent-channel / spurious signals from surrounding mobile communication base stations, V2X communication signals from other vehicles, harmonic radiation from vehicle-mounted millimeter-wave radar, electromagnetic emissions from the vehicle's high-voltage power battery and motor system, and radiated interference from roadside charging piles. These interference sources cover different frequency bands and have different modulation characteristics, forming a complex interference effect on the vehicle-mounted terminal with multiple frequency points and modulation methods. On the other hand, the vehicle is in a continuous state of motion, and the relative distance between the interference source and the vehicle-mounted terminal changes in real time. Furthermore, the interference is affected by obstacles such as buildings, tunnels, and trees, as well as multipath reflection effects. The field strength of the interference signal is not a constant value but exhibits dynamic characteristics such as periodic fluctuations, step abrupt changes, and random fading. In this complex dynamic electromagnetic environment, vehicle-mounted terminals are prone to problems such as decreased communication throughput, increased block error rate, increased transmission delay, and even communication link interruption, thus affecting the normal operation of vehicle-to-everything (V2X) services.

[0004] Current RF immunity testing for automotive terminals is primarily conducted according to automotive electromagnetic compatibility standards such as the ISO 11452 series, GB / T 17626 series, and GB / T 33014. The mainstream testing scheme employs a static continuous wave interference mode with a fixed carrier frequency and fixed field strength, which can only apply steady-state interference with a single modulation method to a single frequency point. This type of testing method has the following drawbacks in practical applications:

[0005] First, the test scenarios deviate significantly from real-world operating conditions, resulting in insufficient test realism. Existing methods can only simulate single-source static interference, failing to reproduce complex interference scenarios involving multiple frequencies and modulation methods, or simulate the dynamic changes in field strength during vehicle operation. This leads to significant differences between laboratory test results and the anti-interference performance of the terminal in actual road operation, making it difficult to effectively expose the product's performance shortcomings in real electromagnetic environments. In some cases, the product may even pass laboratory tests but experience communication failures in actual use.

[0006] Secondly, the testing is not targeted enough and is inefficient. Existing solutions generally adopt a full-band uniform step-size frequency sweep testing mode, which does not distinguish between sensitive and non-sensitive frequencies of the terminal. A large number of redundant tests are performed on non-weak frequency bands, resulting in a long overall testing cycle and low utilization of testing resources. At the same time, because the weak frequencies of the terminal are not located, it is difficult to provide accurate data support for the electromagnetic compatibility optimization design of the product.

[0007] Third, the evaluation of immunity is based on a single dimension and lacks sufficient quantification. Existing tests mostly use "whether the communication link is interrupted" as the core criterion, which only achieves a binary judgment of pass / fail. They lack a continuous quantitative evaluation of the degree of terminal performance degradation during dynamic interference, and do not distinguish between the evaluation logic of positive and negative performance indicators, thus failing to comprehensively and effectively characterize the terminal's radio frequency immunity.

[0008] As 5G vehicle-to-everything (V2X) networks evolve towards higher reliability and lower latency, the electromagnetic compatibility (EMC) reliability requirements for in-vehicle communication terminals continue to increase. Traditional static and single-method radio frequency (RF) immunity testing can no longer meet the needs of industry development. Therefore, there is an urgent need to develop an RF immunity testing method and system that can simulate the real dynamic composite electromagnetic environment of an in-vehicle vehicle and possesses high specificity and high evaluation accuracy. This will improve the authenticity and effectiveness of test results and provide support for the performance optimization and reliability assurance of 5G V2X terminals. Summary of the Invention

[0009] To address this, the present invention provides a dynamic composite radio frequency immunity test method and system for 5G vehicle-to-everything (V2X) terminals, which solves the problem that traditional radio frequency immunity tests are static and singular, and cannot reproduce the real dynamic composite electromagnetic environment of 5G V2X terminals. It also makes up for the shortcomings of traditional technology tests in terms of realism and specificity, and in the difficulty of effectively evaluating the actual immunity performance and positioning performance of the terminal.

[0010] To achieve the above objectives, the present invention provides the following technical solution: a dynamic composite radio frequency immunity test method for 5G vehicle-to-everything (V2X) terminals, comprising the following steps:

[0011] S1. Connect the 5G vehicle-to-everything (V2X) terminal under test to the test environment, establish a stable communication link, collect and record the communication performance benchmark value of the 5G V2X terminal under test in the absence of interference, and set the performance degradation judgment threshold.

[0012] S2. Perform a point-by-point frequency sweep test within the preset test frequency band, gradually increase the interference field strength, monitor the communication performance of the 5G vehicle network terminal under test in real time, and when the performance reaches the performance degradation judgment threshold, mark the corresponding frequency point as a sensitive frequency point and record its critical anti-interference field strength. After traversing, obtain the set of sensitive frequency points.

[0013] S3. For each sensitive frequency point in the set of sensitive frequency points, match the corresponding interference source type and assign an appropriate modulation method. At the same time, configure a dynamic field strength control function for each sensitive frequency point and define the dynamic change law of the interference field strength over time through the dynamic field strength control function.

[0014] S4. The carrier frequency of the fixed interference signal is the corresponding sensitive frequency point. The output field strength of each interference signal is adjusted in real time according to the dynamic field strength control function. Several interference signals with set frequencies and several set modulation methods are combined into dynamic composite radio frequency interference, and the dynamic composite radio frequency interference is applied to the 5G vehicle network terminal under test.

[0015] S5. During the test, the communication performance data of the 5G vehicle-to-everything (V2X) terminal under test is collected in real time. After the test is completed, the communication performance benchmark value is compared, the degree of performance degradation is calculated, and the radio frequency immunity evaluation result of the 5G V2X terminal under test is output.

[0016] As a preferred method for dynamic composite radio frequency immunity testing of 5G vehicle-to-everything (V2X) terminals, in step S2, the frequency sweep test uses a fixed frequency step to traverse the preset test frequency band point by point. At each frequency point, the interference field strength is gradually increased by a fixed step, and each frequency point is stayed for a preset duration to complete the performance judgment. The preset test frequency band covers the working frequency bands of 2G / 3G / 4G / 5G full-mode vehicle communication.

[0017] As a preferred method for dynamic composite radio frequency immunity testing of 5G vehicle-to-everything (V2X) terminals, in step S3, the dynamic field strength control function simulates the field strength change scenario when a vehicle approaches or moves away from an interference source at a constant speed using a sinusoidal periodic fluctuation model. The expression for the sinusoidal periodic fluctuation model is as follows:

[0018]

[0019] In the formula, For the first Sensitive frequency points The instantaneous interference field strength at a given moment. This is the reference field strength at that frequency. This represents the amplitude of the field strength fluctuation at that frequency. The frequency of field strength fluctuations. The initial phase is given; and the constraints are satisfied. This is to ensure that the instantaneous interference field strength is always non-negative.

[0020] As a preferred method for dynamic composite radio frequency immunity testing of 5G vehicle-to-everything (V2X) terminals, in step S3, the dynamic field strength control function simulates field strength abrupt changes caused by vehicles entering and exiting tunnels and obstacle obstruction using a step mutation model. The step mutation model expression is a piecewise function:

[0021]

[0022] In the formula, For the first Sensitive frequency points The instantaneous interference field strength at a given moment. This is the steady-state value for low field strength. This is the steady-state value for high field strength. This is the moment of a sudden increase in field strength. This refers to the abrupt change in field strength; a transition time is configured during engineering implementation. A linear transition is used in the transition interval before and after the abrupt change to match the rising and falling edge characteristics of the hardware output.

[0023] As a preferred method for dynamic composite radio frequency immunity testing of 5G vehicle-to-everything (V2X) terminals, in step S3, the dynamic field strength control function simulates a large-scale random fluctuation scenario caused by multipath reflection and building obstruction in urban areas using a log-normal random fading model. The expression for the log-normal random fading model is as follows:

[0024]

[0025] In the formula, For the first Sensitive frequency points The instantaneous interference field strength at a given moment. This represents the deterministic field strength component at that frequency. To follow a normal distribution The amount of shadow fading, The fading standard deviation is used to characterize the severity of random fluctuations.

[0026] As a preferred method for dynamic composite radio frequency immunity testing of 5G vehicle-to-everything (V2X) terminals, in step S3, during the process of matching the corresponding interference source type and assigning an appropriate modulation method to each sensitive frequency point in the set of sensitive frequency points, the modulation method assigned to each sensitive frequency point includes one or more of amplitude modulation, frequency modulation, pulse modulation, 5G NR digital modulation, and LTE OFDM digital modulation.

[0027] As a preferred method for dynamic composite radio frequency immunity testing of 5G vehicle-to-everything (V2X) terminals, in step S4, during the process of synthesizing interference signals of several set frequencies and several set modulation methods into dynamic composite radio frequency interference, the effective value of the total synthesized field strength is calculated using the principle of incoherent superposition, and the expression is:

[0028]

[0029] In the formula, for The total combined interference field strength at time 10:00 The total number of sensitive frequency points, For the first Sensitive frequency points The instantaneous interference field strength at a given moment.

[0030] As a preferred method for dynamic composite radio frequency immunity testing of 5G vehicle-to-everything (V2X) terminals, in step S5, when calculating the degree of performance degradation, the instantaneous performance degradation degree is calculated separately according to the performance index type:

[0031] For positive performance indicators where larger values ​​generally indicate better performance, the formula is as follows:

[0032]

[0033] For inverse performance metrics where smaller values ​​generally indicate better performance, the formula is as follows:

[0034]

[0035] In the formula, for The instantaneous performance degradation at any given moment. This is the baseline value for communication performance under interference-free conditions. for Actual performance values ​​at any given time.

[0036] As a preferred method for dynamic composite radio frequency immunity testing of 5G vehicle-to-everything (V2X) terminals, step S5 also includes calculating the immunity margin at a single frequency point, using the following formula:

[0037]

[0038] In the formula, For the first Single-frequency interference immunity margin for each sensitive frequency point The critical anti-interference field strength at this frequency point is obtained from the preliminary detection. This refers to the maximum field strength applied at this frequency point during the composite test; the single-frequency immunity margin is used as a reference for immunity margin in the single-frequency dimension and is not used as a direct basis for judging the immunity qualification of composite interference scenarios.

[0039] This invention also provides a dynamic composite radio frequency immunity test system for 5G vehicle-to-everything (V2X) terminals, employing the aforementioned dynamic composite radio frequency immunity test method for 5G V2X terminals, comprising:

[0040] The test benchmark calibration module is used to connect the 5G vehicle-to-everything (V2X) terminal under test to the test environment, establish a stable communication link, collect and record the communication performance benchmark value of the 5G V2X terminal under test under interference-free conditions, and set the performance degradation judgment threshold.

[0041] The sensitive frequency pre-detection module is used to perform point-by-point frequency sweep test within a preset test frequency band, gradually increase the interference field strength, monitor the communication performance of the 5G vehicle network terminal under test in real time, and when the performance reaches the performance degradation judgment threshold, mark the corresponding frequency point as a sensitive frequency point and record its critical anti-interference field strength. After traversal, a set of sensitive frequency points is obtained.

[0042] The dynamic composite test scenario construction module is used to match the corresponding interference source type and assign an appropriate modulation method to each sensitive frequency point in the set of sensitive frequency points. At the same time, it configures a dynamic field strength control function for each of the sensitive frequency points and defines the dynamic change law of the interference field strength over time through the dynamic field strength control function.

[0043] The dynamic composite interference application module is used to fix the carrier frequency of the interference signal as the corresponding sensitive frequency point, adjust the output field strength of each interference signal in real time according to the dynamic field strength control function, combine several interference signals with several set frequencies and several set modulation methods into dynamic composite radio frequency interference, and apply the dynamic composite radio frequency interference to the 5G vehicle network terminal under test.

[0044] The performance monitoring and immunity assessment module is used to collect the communication performance data of the 5G vehicle-to-everything (V2X) terminal under test in real time during the test. After the test is completed, the data is compared with the communication performance benchmark value, the degree of performance degradation is calculated, and the radio frequency immunity assessment result of the 5G V2X terminal under test is output.

[0045] As a preferred solution for a dynamic composite radio frequency immunity test system for 5G vehicle-to-everything (V2X) terminals, the sensitive frequency pre-detection module uses a fixed frequency step size to traverse the preset test frequency band point by point. At each frequency point, the interference field strength is gradually increased in a fixed step, and each frequency point is stayed for a preset duration to complete the performance judgment. The preset test frequency band covers the working frequency bands of 2G / 3G / 4G / 5G full-mode vehicle communication.

[0046] As a preferred solution for a dynamic composite radio frequency immunity testing system for 5G vehicle-to-everything (V2X) terminals, the dynamic composite test scenario construction module uses a sinusoidal periodic fluctuation model to simulate the field strength change scenario when a vehicle approaches or moves away from an interference source at a constant speed. The expression for the sinusoidal periodic fluctuation model is as follows:

[0047]

[0048] In the formula, For the first Sensitive frequency points The instantaneous interference field strength at a given moment. This is the reference field strength at that frequency. This represents the amplitude of the field strength fluctuation at that frequency. The frequency of field strength fluctuations. The initial phase is given; and the constraints are satisfied. This is to ensure that the instantaneous interference field strength is always non-negative.

[0049] As a preferred solution for a dynamic composite radio frequency immunity testing system for 5G vehicle-to-everything (V2X) terminals, the dynamic composite test scenario construction module uses a step mutation model to simulate field strength abrupt changes caused by vehicles entering and exiting tunnels or obstacles. The step mutation model is expressed as a piecewise function.

[0050]

[0051] In the formula, For the first Sensitive frequency points The instantaneous interference field strength at a given moment. This is the steady-state value for low field strength. This is the steady-state value for high field strength. This is the moment of a sudden increase in field strength. This refers to the abrupt change in field strength; a transition time is configured during engineering implementation. A linear transition is used in the transition interval before and after the abrupt change to match the rising and falling edge characteristics of the hardware output.

[0052] As a preferred solution for a dynamic composite radio frequency immunity testing system for 5G vehicle-to-everything (V2X) terminals, the dynamic composite test scenario construction module uses a log-normal random fading model to simulate large-scale random fluctuations caused by multipath reflections and building obstructions in urban areas. The expression for the log-normal random fading model is as follows:

[0053]

[0054] In the formula, For the first Sensitive frequency points The instantaneous interference field strength at a given moment. This represents the deterministic field strength component at that frequency. To follow a normal distribution The amount of shadow fading, The fading standard deviation is used to characterize the severity of random fluctuations.

[0055] As a preferred solution for a dynamic composite radio frequency immunity test system for 5G vehicle-to-everything (V2X) terminals, in the dynamic composite test scenario construction module, during the process of matching the corresponding interference source type and assigning an appropriate modulation method to each sensitive frequency point in the set of sensitive frequency points, the modulation method assigned to each sensitive frequency point includes one or more of amplitude modulation, frequency modulation, pulse modulation, 5G NR digital modulation, and LTE OFDM digital modulation.

[0056] As a preferred solution for a dynamic composite radio frequency immunity testing system for 5G vehicle-to-everything (V2X) terminals, the dynamic composite interference application module, in the process of synthesizing interference signals of several set frequencies and several set modulation methods into dynamic composite radio frequency interference, uses the principle of incoherent superposition to calculate the effective value of the total synthesized field strength, expressed as:

[0057]

[0058] In the formula, for The total combined interference field strength at time 10:00 The total number of sensitive frequency points, For the first Sensitive frequency points The instantaneous interference field strength at a given moment.

[0059] As a preferred solution for a dynamic composite radio frequency immunity testing system for 5G vehicle-to-everything (V2X) terminals, the performance monitoring and immunity assessment module calculates the instantaneous performance degradation degree according to the performance index type when calculating the degree of performance degradation:

[0060] For positive performance indicators where larger values ​​generally indicate better performance, the formula is as follows:

[0061]

[0062] For inverse performance metrics where smaller values ​​generally indicate better performance, the formula is as follows:

[0063]

[0064] In the formula, for The instantaneous performance degradation at any given moment. This is the baseline value for communication performance under interference-free conditions. for Actual performance values ​​at any given time.

[0065] As a preferred solution for dynamic composite radio frequency immunity testing systems for 5G vehicle-to-everything (V2X) terminals, the performance monitoring and immunity assessment module is also used to calculate the immunity margin at a single frequency point. The calculation formula is as follows:

[0066]

[0067] In the formula, For the first Single-frequency interference immunity margin for each sensitive frequency point The critical anti-interference field strength at this frequency point is obtained from the preliminary detection. This refers to the maximum field strength applied at this frequency point during the composite test; the single-frequency immunity margin is used as a reference for immunity margin in the single-frequency dimension and is not used as a direct basis for judging the immunity qualification of composite interference scenarios.

[0068] The present invention has the following advantages:

[0069] This invention uses sinusoidal periodic fluctuations, step abrupt changes, and log-normal random fading dynamic field strength models to simulate typical scenarios such as vehicle movement, sudden occlusion changes, and multipath fading in urban areas. Combined with the superposition of compound interference from multiple frequency points and multiple modulation methods, it highly reproduces the complex dynamic electromagnetic environment of 5G vehicle-to-everything (V2X) terminals in actual operation, effectively reducing the performance deviation between laboratory tests and actual road conditions, and solving the problem of insufficient reference value of traditional static single test results.

[0070] This invention locates the sensitive frequency points and critical immunity field strength of the terminal through pre-scanning, and constructs composite interference test scenarios only for weak frequency bands, avoiding redundant testing caused by blind scanning of the entire frequency band and significantly shortening the test cycle; at the same time, it can lock the frequency point with the weakest immunity of the terminal, providing clear direction and data support for the electromagnetic compatibility optimization design of the product.

[0071] This invention distinguishes between positive and negative performance indicators to establish differentiated instantaneous degradation calculation rules. Combined with single-frequency anti-interference margin indicators, it enables continuous quantitative evaluation of terminal anti-interference performance, breaking through the limitations of the traditional binary judgment of "qualified / unqualified". At the same time, it clarifies the applicable boundaries of each evaluation indicator, avoids misjudgment in complex interference scenarios, and can comprehensively characterize the performance change pattern of the terminal under dynamic interference.

[0072] This invention is compatible with 2G / 3G / 4G / 5G all-mode vehicle-mounted communication terminals, supports two test modes: radio frequency conduction and spatial radiation. The dynamic field strength model, modulation method, and test frequency band can all be flexibly configured as needed. It can be adapted to different carriers such as passenger cars and commercial vehicles, as well as the test needs of various typical driving scenarios such as urban roads, highways, and tunnels. Attached Figure Description

[0073] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings in the following description are merely exemplary, and those skilled in the art can derive other embodiments based on the provided drawings without creative effort.

[0074] The structures, proportions, sizes, etc. illustrated in this specification are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed herein, and are not intended to limit the conditions under which the present invention can be implemented. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportions, or adjustments to the size, without affecting the effects and objectives that the present invention can produce, should still fall within the scope of the technical content disclosed in the present invention.

[0075] Figure 1 This is a schematic diagram of the dynamic composite radio frequency immunity test method for 5G vehicle-to-everything (V2X) terminals provided in an embodiment of the present invention.

[0076] Figure 2 This is a technical roadmap for the dynamic composite radio frequency immunity test method for 5G vehicle-to-everything (V2X) terminals provided in this embodiment of the invention.

[0077] Figure 3 This is a comparison and analysis chart of the test authenticity provided in the embodiments of the present invention;

[0078] Figure 4 This is a relative deviation comparison analysis chart provided in the embodiments of the present invention;

[0079] Figure 5 This is a comparison and analysis chart of testing efficiency provided in the embodiments of the present invention;

[0080] Figure 6This is a sensitive frequency interference immunity margin analysis diagram provided in the embodiments of the present invention;

[0081] Figure 7 This is a diagram of the dynamic composite radio frequency immunity test system for 5G vehicle-to-everything (V2X) terminals provided in this embodiment of the invention. Detailed Implementation

[0082] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. 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.

[0083] Example 1

[0084] See Figure 1 and Figure 2 This invention provides a dynamic composite radio frequency immunity test method for 5G vehicle-to-everything (V2X) terminals, comprising the following steps:

[0085] S1. Connect the 5G vehicle-to-everything (V2X) terminal under test to the test environment, establish a stable communication link, collect and record the baseline communication performance value of the 5G V2X terminal under interference-free conditions, and set a performance degradation judgment threshold. Establish a standard test environment and a stable communication link to eliminate test errors caused by factors such as channel instability and the terminal not reaching a steady state, ensuring the consistency and reproducibility of the initial test conditions. Collect the performance baseline value under interference-free conditions to eliminate the impact of individual differences between different terminals and differences in different test environments on the results, providing a unified reference baseline for performance degradation calculation; without a baseline value, subsequent performance data will lack a basis for comparison, and the impact of interference cannot be quantified. Set a performance degradation judgment threshold to establish a unified quantitative standard for judging interference resistance compliance, avoiding the bias of subjective human judgment. The threshold can be flexibly adjusted according to the reliability requirements of different automotive grades and different business scenarios to adapt to different test needs.

[0086] S2. Perform a point-by-point frequency sweep test within the preset test frequency band, gradually increasing the interference field strength at each point, and monitor the communication performance of the tested 5G vehicle-to-everything (V2X) terminal in real time. When the performance reaches the performance degradation threshold, mark the corresponding frequency point as a sensitive frequency point and record its critical anti-interference field strength. After traversing the entire band, a set of sensitive frequency points is obtained. The step-by-step test method of point-by-point frequency sweep and gradually increasing field strength essentially conducts a comprehensive survey of the terminal's anti-interference capability across the entire frequency band: traversing the target frequency band with a fixed frequency step ensures that no potentially weak frequency points are overlooked. By gradually increasing the field strength, the critical point where the terminal's performance just begins to deteriorate can be captured, obtaining the critical anti-interference field strength parameters, which has higher accuracy than the traditional binary determination using a fixed field strength. After screening out the sensitive frequency points, the composite test only needs to be conducted on these weak frequency points, without consuming test resources in non-sensitive frequency bands. This significantly reduces the overall test time and focuses test resources on the frequency band with the weakest anti-interference capability of the terminal, solving the problems of low efficiency and weak targeting in traditional full-band blind scanning.

[0087] S3. For each sensitive frequency point in the set of sensitive frequency points, match the corresponding interference source type and assign an appropriate modulation method. Simultaneously, configure a dynamic field strength control function for each sensitive frequency point, defining the dynamic change law of the interference field strength over time. In the frequency domain, based on the located sensitive frequency points, match the corresponding interference source in the real vehicle environment to ensure that the interference frequency is consistent with the actual scenario. In the modulation domain, assign the actual modulation method of the corresponding interference source to different frequency points. The spectral structure and mechanism of interference signals of different modulation types are fundamentally different. Analog modulation, pulse modulation, and digital modulation have completely different interference paths and degradation effects on the communication receiver. Matching the actual modulation characteristics can avoid the problem of traditional single continuous wave interference being out of sync with actual operating conditions. In the time domain, configure the dynamic field strength control function to reproduce the time-varying characteristics of the field strength caused by vehicle movement, breaking through the static limitations of traditional fixed field strength testing. This allows the time-domain variation law of interference to conform to the real electromagnetic environment changes during vehicle operation, realizing the construction of a multi-dimensional composite interference scenario that conforms to real operating conditions.

[0088] S4. The carrier frequency of the fixed interference signal corresponds to the sensitive frequency point. The output field strength of each interference signal is adjusted in real time according to the dynamic field strength control function. Several interference signals with set frequencies and modulation methods are combined into a dynamic composite radio frequency interference, which is then applied to the 5G vehicle-to-everything (V2X) terminal under test. Using the control logic of "fixed carrier frequency, dynamic field strength adjustment," the carrier frequency of the interference source in a real scenario is fixed, while the field strength fluctuates with relative distance. This control method perfectly matches the variation pattern of real interference. Multi-channel independent control ensures that the field strength change at each frequency point is executed according to the preset function, and the interference signals do not affect each other. The multi-channel interference is synthesized in a non-coherent manner, conforming to the physical law of superposition of electromagnetic waves of different frequencies, accurately reproducing the composite effect of multiple interference sources acting simultaneously. It is applied to the terminal under test through conduction or radiation, ensuring that the interference energy can accurately couple into the terminal's communication link, realistically simulating the electromagnetic interference experienced by the terminal in actual use.

[0089] S5. During the test, the communication performance data of the tested 5G vehicle-to-everything (V2X) terminal is collected in real time. After the test, the data is compared with the communication performance benchmark value to calculate the degree of performance degradation and output the radio frequency (RF) immunity assessment result of the tested 5G V2X terminal. The real-time acquisition method can completely capture the performance fluctuation details of the terminal throughout the entire dynamic interference process, including instantaneous minimum performance, degradation duration, and performance recovery characteristics, avoiding the problem of missing dynamic transient degradation in traditional solutions that only test steady-state results. The performance degradation degree is calculated by comparing with the benchmark value. Through normalization processing, performance indicators of different dimensions are transformed into a unified degradation degree indicator, enabling horizontal comparison of immunity performance under different frequency bands and scenarios. Simultaneously, the quantified degradation degree can intuitively reflect the severity of interference to the terminal, breaking through the limitations of the traditional binary "qualified / unqualified" judgment. The final output assessment result not only includes a qualification judgment but also locates weak frequency points and quantifies the immunity margin, providing data support for product electromagnetic compatibility optimization design.

[0090] In one possible embodiment, in step S2, the frequency sweep test uses a fixed frequency step to traverse the preset test frequency band point by point, and the interference field strength is gradually increased at each frequency point with a fixed step, and each frequency point is stayed for a preset duration to complete the performance judgment; the preset test frequency band covers the working frequency bands of 2G / 3G / 4G / 5G full-mode vehicle communication.

[0091] Specifically, the frequency sweeping method in this embodiment follows the step-by-step testing principle of electromagnetic compatibility immunity testing. A fixed frequency step size is used to traverse each point, ensuring uniformity of target frequency band coverage and avoiding the omission of potential sensitive frequencies. The step size selection must balance testing efficiency and frequency resolution, typically set according to the corresponding test standard requirements and the receiver's intermediate frequency bandwidth. The interference field strength is progressively increased at each frequency point, accurately capturing the critical field strength value at which terminal performance just begins to deteriorate. This value is a parameter characterizing the terminal's single-frequency immunity capability, offering higher testing accuracy compared to the traditional binary judgment of pass / fail based on a fixed field strength. Each frequency point is paused for a preset duration, waiting for the terminal's communication performance to reach a steady state, avoiding misjudgments caused by transient fluctuations such as channel adaptive adjustment and link reconfiguration. Full-band coverage matches the multi-mode coexistence hardware characteristics of 5G vehicle-to-everything (V2X) terminals. Vehicle terminals typically support 2G / 3G / 4G / 5G multi-band communication simultaneously, and sensitive frequencies may be distributed across any operating frequency band and its adjacent channels and harmonic bands. Full-band coverage ensures the completeness and effectiveness of the test.

[0092] In one possible embodiment, in step S3, the dynamic field strength control function simulates the field strength change scenario when a vehicle approaches or moves away from the interference source at a constant speed using a sinusoidal periodic fluctuation model. The expression for the sinusoidal periodic fluctuation model is:

[0093]

[0094] In the formula, For the first Sensitive frequency points The instantaneous interference field strength at a given moment. This is the reference field strength at that frequency. This represents the amplitude of the field strength fluctuation at that frequency. The frequency of field strength fluctuations. The initial phase is given; and the constraints are satisfied. This is to ensure that the instantaneous interference field strength is always non-negative.

[0095] Specifically, the physical basis of the sinusoidal periodic fluctuation model is the variation law of the interference field strength under the scenario of a vehicle traveling at a constant speed. When a vehicle passes a fixed interference source at a constant speed along a straight line, the relative distance between the two varies with time in a single valley symmetrical about the moment of closest distance. Under free space propagation conditions, the interference field strength is inversely proportional to the propagation distance, and the corresponding field strength exhibits symmetrical single-peak fluctuations, the shape of which is highly similar to the half-period waveform of a sinusoidal function. In engineering, this model can be extended to a sinusoidal periodic function form to simulate the periodic fluctuation of field strength when a vehicle travels back and forth or continuously passes multiple roadside interference sources. The reference field strength corresponds to the average field strength level along the vehicle's travel path, the fluctuation amplitude corresponds to the overall range of field strength variation, the fluctuation frequency is determined by the vehicle's speed and the spatial distribution density of the interference sources, and the initial phase is used to control the field strength state at the start of the test. Constraints Ensuring that the instantaneous field strength is always non-negative—field strength is a scalar physical quantity that characterizes the strength of an electromagnetic field, and it cannot be negative numerically. This constraint ensures the physical rationality of the model and avoids the occurrence of physically meaningless negative field strength calculation results.

[0096] In one possible embodiment, in step S3, the dynamic field strength control function simulates the field strength abrupt change scenarios caused by vehicles entering and exiting tunnels and obstacle occlusion using a step mutation model. The step mutation model is expressed as a piecewise function:

[0097]

[0098] In the formula, For the first Sensitive frequency points The instantaneous interference field strength at a given moment. This is the steady-state value for low field strength. This is the steady-state value for high field strength. This is the moment of a sudden increase in field strength. This refers to the abrupt change in field strength; a transition time is configured during engineering implementation. A linear transition is used in the transition interval before and after the abrupt change to match the rising and falling edge characteristics of the hardware output.

[0099] Specifically, the step-change model corresponds to the occlusion-induced abrupt change scenario in the vehicle's electromagnetic environment. When a vehicle enters a tunnel, a mountain-shaded area, or the shadow area of ​​a large building, the external interference signal is significantly attenuated by the obstacle, and the field strength drops instantly from a high value to a low value. When the vehicle leaves the occluded area, the field strength instantly rises back to a high level. The ideal step function is a simplified abstraction of this physical phenomenon, facilitating theoretical definition and scenario parameter configuration. The ideal step model assumes that the field strength change time is zero. However, in actual testing, the power adjustment of hardware devices such as signal generators and power amplifiers has an inherent response time, making it impossible to output an infinitely steep edge. Therefore, a transition time τ is added in the engineering implementation, using a linear transition method to match the output characteristics of the hardware, ensuring the realism of the scenario simulation, avoiding the current impact of power abrupt changes on the hardware devices, and preventing broadband spurious components generated by abrupt signal changes from interfering with the accuracy of the test results.

[0100] In one possible embodiment, in step S3, the dynamic field strength control function simulates a large-scale random fluctuation scenario caused by multipath reflection and building shading in urban areas using a log-normal random fading model. The expression for the log-normal random fading model is as follows:

[0101]

[0102] In the formula, For the first Sensitive frequency points The instantaneous interference field strength at a given moment. This represents the deterministic field strength component at that frequency. To follow a normal distribution The amount of shadow fading, The fading standard deviation is used to characterize the severity of random fluctuations.

[0103] Specifically, the log-normal random fading model is based on classic experimental findings of large-scale shadow fading in wireless channels. In urban environments, electromagnetic wave propagation is randomly blocked by obstacles such as buildings, trees, and terrain, causing the received signal strength to exhibit random fluctuations on a macroscopic scale. Extensive channel measurement data shows that the field strength in decibels of this type of shadow fading follows a normal distribution, while the corresponding linear field strength follows a log-normal distribution. The model employs a multiplicative structure because shadow fading is a random modulation of the average field strength, belonging to multiplicative interference rather than additive interference; therefore, multiplying the deterministic component by a random fading coefficient is more consistent with the physical nature of the problem. The standard conversion formula from decibel value to a linear multiple of field strength is: Field strength in decibels is defined as... The known fading decibel value When, the field strength multiple in the linear domain is This conversion ensures consistency between the dimensions and the physical meaning. The model naturally guarantees that the instantaneous field strength is positive, and it has higher physical rigor compared to the additive normal noise model. The value of the fading standard deviation σ is strongly correlated with the scene, with a larger σ value in densely built-up urban areas and a smaller σ value in open suburban scenes.

[0104] In one possible embodiment, in step S3, during the process of matching the corresponding interference source type and assigning an appropriate modulation method to each sensitive frequency point in the set of sensitive frequency points, the modulation method assigned to each sensitive frequency point includes one or more of amplitude modulation, frequency modulation, pulse modulation, 5G NR digital modulation, and LTE OFDM digital modulation.

[0105] Specifically, interference signals with different modulation schemes exhibit significant differences in their spectral structure, power distribution, and time-domain characteristics, resulting in entirely different interference mechanisms on communication receivers. Amplitude modulation (AM) and frequency modulation (FM) interference are analog single-frequency interferences, primarily affecting the receiving link through adjacent channel power leakage and receiver intermediate frequency feedthrough. Pulse modulation interference (such as vehicle radar signals) has high peak power and low duty cycle, easily triggering transient saturation and baseband errors in the receiver front-end. Digital modulation interference such as 5G NR and LTE OFDM is broadband interference, degrading the signal-to-noise ratio of the communication link through adjacent channel power superposition and co-channel interference. Various interference sources in real vehicle electromagnetic environments possess specific modulation schemes. Therefore, matching the modulation scheme of the corresponding real interference source to sensitive frequencies allows the time-domain and frequency-domain characteristics of the tested interference to closely match actual operating conditions, avoiding the problem of discrepancies between traditional single continuous wave interference and actual interference characteristics, and significantly improving the authenticity and engineering reference value of the test results.

[0106] In one possible embodiment, in step S4, during the process of synthesizing several interference signals of set frequencies and several set modulation methods into dynamic composite radio frequency interference, the effective value of the total composite field strength is calculated using the principle of incoherent superposition, and the expression is:

[0107]

[0108] In the formula, for The total combined interference field strength at time 10:00 The total number of sensitive frequency points, For the first Sensitive frequency points The instantaneous interference field strength at a given moment.

[0109] Specifically, there is no stable phase difference between sinusoidal electromagnetic waves of different frequencies, and no continuous interference enhancement or destructive effect occurs. The total electromagnetic power is equal to the algebraic sum of the powers of each signal. Since the average power density of an electromagnetic wave is proportional to the square of the effective field strength (…),… Therefore, the total power corresponds to the square of the total electric field strength, i.e. The effective value of the total field strength is obtained by taking the square root. If the signals are coherent signals with the same frequency and phase, the total field strength is calculated by vector superposition (algebraic sum). However, in this invention, each sensitive frequency point is an interference signal of a different frequency, which meets the applicable conditions for incoherent superposition. Therefore, the square root of the sum of squares is used for calculation, which conforms to the industry-standard specifications for multi-frequency interference synthesis in the field of electromagnetic field theory and electromagnetic compatibility.

[0110] In one possible embodiment, in step S5, when calculating the degree of performance degradation, the instantaneous performance degradation degree is calculated separately according to the performance index type:

[0111] For positive performance indicators where larger values ​​generally indicate better performance, the formula is as follows:

[0112]

[0113] For inverse performance metrics where smaller values ​​generally indicate better performance, the formula is as follows:

[0114]

[0115] In the formula, for The instantaneous performance degradation at any given moment. This is the baseline value for communication performance under interference-free conditions. for Actual performance values ​​at any given time.

[0116] Specifically, degradation degrees are calculated separately for positive and negative indicators to ensure a consistent physical meaning: a higher degradation degree indicates a more severe performance degradation. Positive performance indicators (such as downlink throughput and receiver sensitivity) are characterized by higher values ​​indicating better performance; performance degradation under interference manifests as a decrease in the measured value. Therefore, the degree of degradation is represented by the ratio of the difference between the measured and actual values ​​to the baseline value. Negative performance indicators (such as block error rate, packet loss rate, and end-to-end latency) are characterized by lower values ​​indicating better performance; performance degradation under interference manifests as an increase in the measured value. Therefore, the standard calculation logic is to represent the degree of degradation by the ratio of the difference between the measured and actual values ​​to the baseline value. Using a percentage-based degradation degree normalizes performance indicators, allowing for horizontal comparison of performance indicators of different dimensions and magnitudes on the same dimension. This facilitates a comprehensive evaluation of the terminal's overall anti-interference performance and also makes it easier to set a unified degradation judgment threshold.

[0117] In one possible embodiment, step S5 further includes calculating the single-frequency interference immunity margin, using the following formula:

[0118]

[0119] In the formula, For the first Single-frequency interference immunity margin for each sensitive frequency point The critical anti-interference field strength at this frequency point is obtained from the preliminary detection. This refers to the maximum field strength applied at this frequency point during the composite test; the single-frequency immunity margin is used as a reference for immunity margin in the single-frequency dimension and is not used as a direct basis for judging the immunity qualification of composite interference scenarios.

[0120] Specifically, immunity margin is an indicator in the field of electromagnetic compatibility (EMC) that characterizes the safety margin of a device's immunity to interference. Its physical meaning is the difference between the device's tolerance threshold and the actual applied interference intensity. A positive margin indicates that the actual interference intensity is lower than the device's tolerance limit, and the device has a safety margin; a negative margin indicates that the interference intensity exceeds the device's tolerance capability, and the device will experience performance degradation. The critical immunity field strength is the tolerance threshold under independent interference at a single frequency. It is particularly important to note that single-frequency margin cannot be directly used to determine performance in complex scenarios. This is because multi-frequency complex interference has a synergistic effect. When multiple interferences that have not reached the single-frequency critical value act simultaneously, they may collectively lead to terminal performance degradation through mechanisms such as in-band power superposition, receiver nonlinear intermodulation, and baseband symbol interference accumulation. This degradation effect is stronger than the independent effect of a single interference. Therefore, single-frequency immunity margin can only be used as a single-dimensional reference. The immunity capability in complex interference scenarios needs to be comprehensively judged based on actual test results to avoid misjudgments such as a positive single-frequency margin but performance exceeding limits in complex scenarios.

[0121] To quantitatively verify the technical effectiveness of the dynamic composite radio frequency immunity test method for 5G vehicle-to-everything (V2X) terminals proposed in this invention, a comparative test scheme was adopted: the industry-standard traditional static single-frequency radio frequency immunity test method was used as the control group, and the dynamic composite test method of this invention was used as the experimental group. At the same time, the results of real vehicle road tests were used as the true value reference for real operating conditions. The comparative verification was carried out from four dimensions: test authenticity, test efficiency, accuracy of sensitive frequency point positioning, and accuracy of immunity assessment, to prove the significant advantages of this invention over the prior art. The specific test contents are as follows.

[0122] I. Test Environment and Equipment

[0123] Test subjects: 3 mass-produced 5G vehicle-mounted T-BOX terminals from the same batch, supporting 5G NR n77 frequency band and LTE FDD standard, with identical hardware and software firmware versions, and basic performance calibration completed before the test, with individual performance deviations of less than 1%.

[0124] Test instruments: 5G communication comprehensive tester, four-channel RF signal generator, linear power amplifier, RF combiner, conducted test fixture, high-precision attenuator, metrology-grade RF cable; all test equipment is calibrated by a legal metrology institution, and the test uncertainty meets the requirements of GB / T33014 series standards.

[0125] Benchmark test conditions: ambient temperature 25℃±2℃, terminal power supply voltage 13.5V DC; test main frequency band 3300MHz~4200MHz (5G n77 mainstream operating frequency band); benchmark service configuration is downlink full buffer data transmission, subcarrier spacing 30kHz, bandwidth 100MHz.

[0126] II. Experimental Design

[0127] This experiment compares the overall effectiveness of the testing methods. Both the control and experimental groups followed their respective standard procedures, using real-vehicle road test results as a reference for actual operating conditions. The experiment verified the degree to which the two laboratory methods reproduced the real electromagnetic environment of an in-vehicle vehicle and their testing efficiency. The tested terminal, initial communication state, environment, and power supply conditions were completely consistent; only the testing methods differed.

[0128] Control Group A (Traditional Static Single-Frequency Test): Performed according to the general test specifications for vehicle electromagnetic compatibility, using unmodulated continuous wave interference with fixed carrier frequency and fixed field strength, and conducting point-by-point frequency sweep test across the entire frequency band to output the pass / fail judgment result.

[0129] Experimental Group B (Dynamic Composite Test of this Invention): The entire process of sensitive frequency point pre-detection, dynamic scene construction, composite interference application, and quantitative evaluation is performed. A sinusoidal periodic fluctuation field strength model and multi-modulation composite interference are used to output multi-dimensional quantitative evaluation results.

[0130] Reference Group C (Real Vehicle Road Test): Real vehicle tests are conducted on typical urban commuter roads to collect communication performance data under actual terminal operation, which serves as a true reference for operating conditions.

[0131] III. Experimental Procedure

[0132] 1. Reference performance calibration

[0133] The terminal under test was connected to the conducted test environment, and a stable communication link was established with the 5G comprehensive test instrument. The test was conducted continuously for 5 minutes under interference-free conditions, and the downlink average throughput and average block error rate were recorded as performance benchmark values. Each of the three terminals was tested three times, and the average value was taken. The final benchmark performance was: downlink average throughput of 982 Mbps, average block error rate of 0.012%, with no link drops or reconnections.

[0134] Set the performance degradation judgment threshold: downlink throughput is lower than 70% of the baseline value (i.e., 687.4Mbps), or the block error rate is higher than 1%, or a communication link is dropped.

[0135] 2. Control Group A: Traditional static single-frequency test performed.

[0136] (21) Set the frequency sweep band to 3300MHz~4200MHz, with a frequency step of 5MHz, for a total of 181 test frequency points;

[0137] (22) Apply unmodulated continuous wave interference with a fixed field strength of 8V / m to each frequency point, stay at each frequency point for 30s, and record the terminal throughput and block error rate at that frequency point;

[0138] (23) For frequency points where performance deteriorates significantly, the critical anti-interference field strength under unmodulated continuous wave is tested by gradually increasing the field strength.

[0139] (24) Calculate the total test duration and output the pass / fail judgment results and performance data of each frequency point.

[0140] 3. Experimental Group B: The Method of the Invention

[0141] (31) Sensitive frequency pre-detection: A fast step-scanning screening strategy is adopted. The frequency band of 3300MHz~4200MHz is traversed in 5MHz step size. The field strength of non-sensitive frequency points is increased by only 2~3 levels. After confirming that there is no obvious degradation, the frequency point is skipped to the next frequency point. The field strength of suspected sensitive frequency points is increased step by step. When the terminal performance reaches the degradation threshold, it is marked as a sensitive frequency point and the critical anti-interference field strength under the corresponding modulation signal is recorded. Finally, the set of sensitive frequency points is output.

[0142] (32) Dynamic scene configuration: For the three sensitive frequency points (3480MHz, 3725MHz, 3910MHz) obtained by positioning, 5G NR QPSK digital modulation, pulse modulation (pulse width 1μs, repetition frequency 1kHz) and LTE OFDM digital modulation are matched respectively; a sinusoidal periodic fluctuation field strength model is configured, with the field strength variation range of 3V / m~10V / m and the fluctuation period of 12s.

[0143] (33) Dynamic composite interference test: Start the three-channel signal generator to output interference signal synchronously, and inject it into the terminal under test through the conduction fixture after incoherent synthesis; continuously test for 6 fluctuation cycles for a total of 72s, and collect the terminal throughput, error rate, connection status and other performance data in real time at a sampling rate of 10Hz.

[0144] (34) Calculate the total test duration, instantaneous performance degradation and single-frequency interference immunity margin, and output the complete evaluation results.

[0145] 4. Reference Group C: Real-vehicle road testing

[0146] The same model terminal was installed on the roof of the test vehicle, equipped with a standard vehicle-mounted shark fin antenna, and driven at a constant speed of 60km / h on a main urban road for 30 minutes, maintaining full-buffer 5G downlink data transmission throughout the journey; the downlink throughput, block error rate, and number of link reconnections during the journey were recorded as a true performance reference under real working conditions.

[0147] IV. Experimental Results and Analysis

[0148] (a) Comparison of test authenticity (verification of working condition fit)

[0149] Using real-vehicle road test results as the true benchmark, the core performance indicators of the two laboratory testing methods were compared, and the relative deviation was calculated (relative deviation = |laboratory test value - road test value| / road test value × 100%). The results are shown in [link to results]. Figure 3 Figure 4 and Table 1:

[0150] Table 1 Comparison of Test Authenticity

[0151]

[0152] Traditional static testing uses unmodulated continuous wave interference with a single frequency and fixed field strength, which differs significantly from the characteristics of multi-source modulated interference and dynamic field strength fluctuations in real-world vehicle environments. On one hand, the terminal's immunity to unmodulated continuous waves is significantly stronger than that of various modulated signals, with only slight performance degradation under 8V / m continuous waves. On the other hand, static fixed field strength cannot reproduce the transient high field strength impact caused by vehicle movement, therefore the measured performance degradation is far lower than in real-world scenarios, with throughput deviations exceeding 75%, severely underestimating the actual electromagnetic interference risk.

[0153] The method of this invention reproduces time-varying characteristics by matching real modulation methods at multiple frequency points and using dynamic field strength functions. It highly restores the real vehicle electromagnetic environment from three dimensions: frequency domain, modulation domain, and time domain. The deviation between the test results and the actual road test is controlled within 5%. It can effectively reproduce the performance degradation effect under real working conditions, significantly improve the test authenticity and engineering reference value, and solve the core problem of the disconnect between traditional static testing and actual working conditions.

[0154] (II) Comparison of testing efficiency (verification of resource utilization)

[0155] The total time and effective test percentage for completing full-band immunity testing using the two methods (effective test time for sensitive frequencies / total test time) were statistically analyzed. See the results below. Figure 5 and Table 2:

[0156] Table 2 Comparison of Test Efficiency

[0157]

[0158] Traditional methods require performing fixed field strength tests on all 181 frequency points across the entire frequency band, the vast majority of which are non-sensitive frequencies. This results in extremely high test redundancy, with less than 2% of tests being effective, leading to long overall testing cycles and low utilization of test resources. This invention rapidly identifies three core sensitive frequencies through a pre-detection step, enabling high-precision composite interference testing only on these vulnerable frequencies. Furthermore, the pre-detection employs a rapid screening strategy, eliminating the need for step-by-step testing of non-sensitive frequencies to reach critical values, significantly reducing the overall screening time. The total testing time is reduced by approximately 66% compared to traditional methods, and test resources are concentrated on high-risk sensitive frequencies, increasing the effective testing rate to over 80%, achieving a simultaneous improvement in testing efficiency and targeting.

[0159] (III) Verification of the accuracy of sensitive frequency point positioning

[0160] The three sensitive frequency points (3480MHz, 3725MHz, and 3910MHz) located in the pre-detection step of this invention are completely consistent with the three frequency points with the most severe performance degradation obtained by traditional full-band frequency sweeping; the error between the critical immunity field strength test value and the traditional refined test result is less than 0.2V / m, and the frequency point location accuracy reaches 100%. The verification results show that the pre-detection step can accurately locate the weak frequency points of the terminal's immunity while significantly reducing the test time, ensuring the integrity of the test coverage and providing precise targets for subsequent composite interference testing and product electromagnetic compatibility optimization.

[0161] (iv) Comparison of the accuracy of disturbance rejection assessment

[0162] Traditional static testing can only output a binary judgment result of "pass / fail", which cannot quantify the degree of degradation and safety margin, nor can it distinguish the immunity shortcomings of different frequency points.

[0163] See Figure 6 This invention's method can output multi-dimensional quantitative data such as instantaneous performance degradation curves, single-frequency immunity margins, and performance recovery characteristics. Calculations show that the immunity margin at 3480MHz is -2.2V / m, at 3725MHz it is -2.8V / m, and at 3910MHz it is -1.5V / m. The 3725MHz frequency band has the lowest immunity margin, perfectly matching the pattern of most significant interference in this frequency band observed in road testing, effectively guiding the electromagnetic compatibility optimization of products. Furthermore, this method clearly distinguishes the degradation calculation logic for forward / reverse performance indicators and clearly defines the applicable boundaries of single-frequency immunity margins. The rigor and accuracy of the evaluation system are significantly superior to traditional methods.

[0164] In summary, the results of this comparative experiment fully demonstrate the technical effectiveness of the present invention:

[0165] The realism of the test has been greatly improved: the test results are highly consistent with the actual road scenario, and the deviation of the core performance indicators has been reduced from more than 75% of the traditional method to less than 5%, which effectively solves the problems of large deviation between traditional static test and actual working conditions and underestimation of interference risk;

[0166] Testing efficiency has been significantly improved: the total testing time has been reduced by about 66%, testing resources have been concentrated on sensitive and vulnerable frequency points, and the effective testing rate has increased from less than 2% to more than 80%.

[0167] The evaluation system is comprehensively quantified: it can effectively locate weak frequency points in anti-interference and quantify the anti-interference safety margin. The evaluation dimensions and accuracy are significantly better than the traditional binary judgment method, and can provide clear data support for product electromagnetic compatibility optimization.

[0168] Example 2

[0169] See Figure 7Embodiment 2 of the present invention also provides a dynamic composite radio frequency immunity test system for 5G vehicle-to-everything (V2X) terminals, employing the dynamic composite radio frequency immunity test method for 5G V2X terminals described in the above embodiments, including:

[0170] The test benchmark calibration module 100 is used to connect the 5G vehicle network terminal under test to the test environment, establish a stable communication link, collect and record the communication performance benchmark value of the 5G vehicle network terminal under test under interference-free conditions, and set the performance degradation judgment threshold.

[0171] The sensitive frequency pre-detection module 200 is used to perform point-by-point frequency sweep test within a preset test frequency band, gradually increase the interference field strength, monitor the communication performance of the 5G vehicle network terminal under test in real time, and when the performance reaches the performance degradation judgment threshold, mark the corresponding frequency point as a sensitive frequency point and record its critical anti-interference field strength. After traversal, a set of sensitive frequency points is obtained.

[0172] The dynamic composite test scenario construction module 300 is used to match the corresponding interference source type and assign an appropriate modulation method to each sensitive frequency point in the set of sensitive frequency points, and at the same time configure a dynamic field strength control function for each of the sensitive frequency points, and define the dynamic change law of the interference field strength over time through the dynamic field strength control function.

[0173] The dynamic composite interference application module 400 is used to fix the carrier frequency of the interference signal as the corresponding sensitive frequency point, adjust the output field strength of each interference signal in real time according to the dynamic field strength control function, combine a number of interference signals with a set frequency and a number of set modulation methods into dynamic composite radio frequency interference, and apply the dynamic composite radio frequency interference to the 5G vehicle network terminal under test.

[0174] The performance monitoring and immunity assessment module 500 is used to collect the communication performance data of the 5G vehicle-to-everything (V2X) terminal under test in real time during the test, compare it with the communication performance benchmark value after the test is completed, calculate the degree of performance degradation, and output the radio frequency immunity assessment result of the 5G V2X terminal under test.

[0175] In one possible embodiment, in the sensitive frequency point pre-detection module 200, the frequency sweep test uses a fixed frequency step to traverse the preset test frequency band point by point, and the interference field strength is gradually increased at each frequency point with a fixed step, and each frequency point is stayed for a preset duration to complete the performance judgment; the preset test frequency band covers the working frequency bands of 2G / 3G / 4G / 5G full-mode vehicle communication.

[0176] In one possible embodiment, in the dynamic composite test scenario construction module 300, the dynamic field strength control function simulates the field strength change scenario when a vehicle approaches or moves away from the interference source at a constant speed using a sinusoidal periodic fluctuation model. The expression of the sinusoidal periodic fluctuation model is as follows:

[0177]

[0178] In the formula, For the first Sensitive frequency points The instantaneous interference field strength at a given moment. This is the reference field strength at that frequency. This represents the amplitude of the field strength fluctuation at that frequency. The frequency of field strength fluctuations. The initial phase is given; and the constraints are satisfied. This is to ensure that the instantaneous interference field strength is always non-negative.

[0179] In one possible embodiment, in the dynamic composite test scenario construction module 300, the dynamic field strength control function simulates the field strength abrupt change scenarios caused by vehicles entering and exiting tunnels and obstacle occlusion using a step mutation model. The step mutation model expression is a piecewise function:

[0180]

[0181] In the formula, For the first Sensitive frequency points The instantaneous interference field strength at a given moment. This is the steady-state value for low field strength. This is the steady-state value for high field strength. This is the moment of a sudden increase in field strength. This refers to the abrupt change in field strength; a transition time is configured during engineering implementation. A linear transition is used in the transition interval before and after the abrupt change to match the rising and falling edge characteristics of the hardware output.

[0182] In one possible embodiment, in the dynamic composite test scenario construction module 300, the dynamic field strength control function simulates a large-scale random fluctuation scenario caused by multipath reflection and building occlusion in urban areas using a log-normal random fading model. The expression for the log-normal random fading model is as follows:

[0183]

[0184] In the formula, For the first Sensitive frequency points The instantaneous interference field strength at a given moment. This represents the deterministic field strength component at that frequency. To follow a normal distribution The amount of shadow fading, The fading standard deviation is used to characterize the severity of random fluctuations.

[0185] In one possible embodiment, in the dynamic composite test scenario construction module 300, during the process of matching the corresponding interference source type and assigning an appropriate modulation method to each sensitive frequency point in the sensitive frequency point set, the modulation method assigned to each sensitive frequency point includes one or more of amplitude modulation, frequency modulation, pulse modulation, 5G NR digital modulation, and LTE OFDM digital modulation.

[0186] In one possible embodiment, in the dynamic composite interference application module 400, during the process of synthesizing interference signals of several set frequencies and several set modulation methods into dynamic composite radio frequency interference, the effective value of the total composite field strength is calculated using the principle of incoherent superposition, and the expression is:

[0187]

[0188] In the formula, for The total combined interference field strength at time 10:00 The total number of sensitive frequency points, For the first Sensitive frequency points The instantaneous interference field strength at a given moment.

[0189] In one possible embodiment, in the performance monitoring and immunity assessment module 500, when calculating the degree of performance degradation, the instantaneous performance degradation degree is calculated separately according to the performance index type:

[0190] For positive performance indicators where larger values ​​generally indicate better performance, the formula is as follows:

[0191]

[0192] For inverse performance metrics where smaller values ​​generally indicate better performance, the formula is as follows:

[0193]

[0194] In the formula, for The instantaneous performance degradation at any given moment. This is the baseline value for communication performance under interference-free conditions. for Actual performance values ​​at any given time.

[0195] In one possible embodiment, the performance monitoring and immunity assessment module 500 is further used to calculate the immunity margin at a single frequency point, using the following formula:

[0196]

[0197] In the formula, For the first Single-frequency interference immunity margin for each sensitive frequency point The critical anti-interference field strength at this frequency point is obtained from the preliminary detection. This refers to the maximum field strength applied at this frequency point during the composite test; the single-frequency immunity margin is used as a reference for immunity margin in the single-frequency dimension and is not used as a direct basis for judging the immunity qualification of composite interference scenarios.

[0198] It should be noted that the information interaction and execution process between the various units of the above system are based on the same concept as the method embodiment in Embodiment 1 of this application, and the resulting technical effects are the same as those in the method embodiment of this application. For details, please refer to the description in the method embodiment shown above in this application, and it will not be repeated here.

[0199] Example 3

[0200] Embodiment 3 of the present invention provides a non-transitory computer-readable storage medium storing program code for a dynamic composite radio frequency immunity test method for 5G vehicle-to-everything (V2X) terminals. The program code includes instructions for executing the dynamic composite radio frequency immunity test method for 5G V2X terminals as described in Embodiment 1 or any possible implementation thereof.

[0201] Computer-readable storage media can be any available medium that a computer can access, or a data storage device such as a server or data center that integrates one or more available media. The available medium can be magnetic media (e.g., floppy disks, hard disks, magnetic tapes), optical media (e.g., DVDs), or semiconductor media (e.g., solid-state drives (SSDs)).

[0202] Example 4

[0203] Embodiment 4 of the present invention provides an electronic device, including: a memory and a processor;

[0204] The processor and the memory communicate with each other via a bus; the memory stores program instructions that can be executed by the processor, and the processor can call the program instructions to execute the dynamic composite radio frequency immunity test method for 5G vehicle-to-everything (V2X) terminals according to Embodiment 1 or any possible implementation thereof.

[0205] Specifically, a processor can be implemented in hardware or software. When implemented in hardware, the processor can be a logic circuit, an integrated circuit, etc. When implemented in software, the processor can be a general-purpose processor that reads software code stored in memory. This memory can be integrated into the processor or located outside the processor and exist independently.

[0206] In the above embodiments, implementation can be achieved, in whole or in part, through software, hardware, firmware, or any combination thereof. When implemented in software, it can be implemented, in whole or in part, as a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or part of the processes or functions described in the embodiments of the present invention are generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired (e.g., coaxial cable, fiber optic, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means.

[0207] It is obvious to those skilled in the art that the modules or steps of the present invention described above can be implemented using general-purpose computing devices. They can be centralized on a single computing device or distributed across a network of multiple computing devices. Optionally, they can be implemented using computer-executable program code, thereby storing them in a storage device for execution by a computing device. In some cases, the steps shown or described can be performed in a different order than those presented herein, or they can be fabricated as separate integrated circuit modules, or multiple modules or steps can be fabricated as a single integrated circuit module. Thus, the present invention is not limited to any particular combination of hardware and software.

[0208] Although the present invention has been described in detail above with general descriptions and specific embodiments, modifications or improvements can be made to it, which will be obvious to those skilled in the art. Therefore, all such modifications or improvements made without departing from the spirit of the present invention fall within the scope of protection claimed by the present invention.

Claims

1. A dynamic composite radio frequency immunity test method for 5G vehicle-to-everything (V2X) terminals, characterized in that, Includes the following steps: S1. Connect the 5G vehicle-to-everything (V2X) terminal under test to the test environment, establish a stable communication link, collect and record the communication performance benchmark value of the 5G V2X terminal under test in the absence of interference, and set the performance degradation judgment threshold. S2. Perform a point-by-point frequency sweep test within the preset test frequency band, gradually increase the interference field strength, monitor the communication performance of the 5G vehicle network terminal under test in real time, and when the performance reaches the performance degradation judgment threshold, mark the corresponding frequency point as a sensitive frequency point and record its critical anti-interference field strength. After traversing, obtain the set of sensitive frequency points. S3. For each sensitive frequency point in the set of sensitive frequency points, match the corresponding interference source type and assign an appropriate modulation method. At the same time, configure a dynamic field strength control function for each sensitive frequency point and define the dynamic change law of the interference field strength over time through the dynamic field strength control function. S4. The carrier frequency of the fixed interference signal is the corresponding sensitive frequency point. The output field strength of each interference signal is adjusted in real time according to the dynamic field strength control function. Several interference signals with set frequencies and several set modulation methods are combined into dynamic composite radio frequency interference, and the dynamic composite radio frequency interference is applied to the 5G vehicle network terminal under test. S5. During the test, the communication performance data of the 5G vehicle-to-everything (V2X) terminal under test is collected in real time. After the test is completed, the communication performance benchmark value is compared, the degree of performance degradation is calculated, and the radio frequency immunity evaluation result of the 5G V2X terminal under test is output.

2. The dynamic composite radio frequency immunity test method for 5G vehicle-to-everything (V2X) terminals according to claim 1, characterized in that, In step S2, the frequency sweep test uses a fixed frequency step to traverse the preset test frequency band point by point. At each frequency point, the interference field strength is gradually increased by a fixed step, and each frequency point is stayed for a preset duration to complete the performance judgment. The preset test frequency band covers the working frequency bands of 2G / 3G / 4G / 5G full-mode vehicle communication.

3. The dynamic composite radio frequency immunity test method for 5G vehicle-to-everything (V2X) terminals according to claim 1, characterized in that, In step S3, the dynamic field strength control function simulates the field strength change scenario when a vehicle approaches or moves away from the interference source at a constant speed using a sinusoidal periodic fluctuation model. The expression for the sinusoidal periodic fluctuation model is as follows: ， In the formula, For the first Sensitive frequency points The instantaneous interference field strength at a given moment. This is the reference field strength at that frequency. This represents the amplitude of the field strength fluctuation at that frequency. The frequency of field strength fluctuations. The initial phase is given; and the constraint conditions are satisfied. This is to ensure that the instantaneous interference field strength is always non-negative.

4. The dynamic composite radio frequency immunity test method for 5G vehicle-to-everything (V2X) terminals according to claim 1, characterized in that, In step S3, the dynamic field strength control function simulates the field strength abrupt change scenarios caused by vehicles entering and exiting tunnels and obstacle occlusion using a step mutation model. The step mutation model expression is a piecewise function: ， In the formula, For the first Sensitive frequency points The instantaneous interference field strength at a given moment. This is the steady-state value for low field strength. This is the steady-state value for high field strength. This is the moment of a sudden increase in field strength. This refers to the abrupt change in field strength; a transition time is configured during engineering implementation. A linear transition is used in the transition interval before and after the abrupt change to match the rising and falling edge characteristics of the hardware output.

5. The dynamic composite radio frequency immunity test method for 5G vehicle-to-everything (V2X) terminals according to claim 1, characterized in that, In step S3, the dynamic field strength control function simulates a large-scale random fluctuation scenario caused by multipath reflection and building shading in urban areas using a log-normal random fading model. The expression for the log-normal random fading model is as follows: ， In the formula, For the first Sensitive frequency points The instantaneous interference field strength at a given moment. This represents the deterministic field strength component at that frequency. To follow a normal distribution The amount of shadow fading, The fading standard deviation is used to characterize the severity of random fluctuations.

6. The dynamic composite radio frequency immunity test method for 5G vehicle-to-everything (V2X) terminals according to claim 1, characterized in that, In step S3, during the process of matching the corresponding interference source type and assigning an appropriate modulation method to each sensitive frequency point in the set of sensitive frequency points, the modulation method assigned to each sensitive frequency point includes one or more of amplitude modulation, frequency modulation, pulse modulation, 5G NR digital modulation, and LTE OFDM digital modulation.

7. The dynamic composite radio frequency immunity test method for 5G vehicle-to-everything (V2X) terminals according to claim 1, characterized in that, In step S4, during the process of synthesizing several interference signals with set frequencies and modulation methods into dynamic composite radio frequency interference, the effective value of the total composite field strength is calculated using the principle of incoherent superposition. The expression is as follows: ， In the formula, for The total combined interference field strength at time 10:00 The total number of sensitive frequency points, For the first Sensitive frequency points The instantaneous interference field strength at a given moment.

8. The dynamic composite radio frequency immunity test method for 5G vehicle-to-everything (V2X) terminals according to claim 1, characterized in that, In step S5, when calculating the degree of performance degradation, the instantaneous performance degradation degree is calculated separately according to the performance index type: For positive performance indicators where larger values ​​generally indicate better performance, the formula is as follows: ， For inverse performance metrics where smaller values ​​generally indicate better performance, the formula is as follows: ， In the formula, for The instantaneous performance degradation at any given moment. This is the baseline value for communication performance under interference-free conditions. for Actual performance values ​​at any given time.

9. The dynamic composite radio frequency immunity test method for 5G vehicle-to-everything (V2X) terminals according to claim 1, characterized in that, Step S5 also includes calculating the single-frequency interference immunity margin, using the following formula: ， In the formula, For the first Single-frequency interference immunity margin for each sensitive frequency point The critical anti-interference field strength at this frequency point is obtained from the preliminary detection. This refers to the maximum field strength applied at this frequency point during the composite test; the single-frequency immunity margin is used as a reference for immunity margin in the single-frequency dimension and is not used as a direct basis for judging the immunity qualification of composite interference scenarios.

10. A dynamic composite radio frequency immunity test system for 5G vehicle-to-everything (V2X) terminals, employing the dynamic composite radio frequency immunity test method for 5G V2X terminals as described in any one of claims 1 to 9, characterized in that, include: The test benchmark calibration module is used to connect the 5G vehicle-to-everything (V2X) terminal under test to the test environment, establish a stable communication link, collect and record the communication performance benchmark value of the 5G V2X terminal under test under interference-free conditions, and set the performance degradation judgment threshold. The sensitive frequency pre-detection module is used to perform point-by-point frequency sweep test within a preset test frequency band, gradually increase the interference field strength, monitor the communication performance of the 5G vehicle network terminal under test in real time, and when the performance reaches the performance degradation judgment threshold, mark the corresponding frequency point as a sensitive frequency point and record its critical anti-interference field strength. After traversal, a set of sensitive frequency points is obtained. The dynamic composite test scenario construction module is used to match the corresponding interference source type and assign an appropriate modulation method to each sensitive frequency point in the set of sensitive frequency points. At the same time, it configures a dynamic field strength control function for each of the sensitive frequency points and defines the dynamic change law of the interference field strength over time through the dynamic field strength control function. The dynamic composite interference application module is used to fix the carrier frequency of the interference signal as the corresponding sensitive frequency point, adjust the output field strength of each interference signal in real time according to the dynamic field strength control function, combine several interference signals with several set frequencies and several set modulation methods into dynamic composite radio frequency interference, and apply the dynamic composite radio frequency interference to the 5G vehicle network terminal under test. The performance monitoring and immunity assessment module is used to collect the communication performance data of the 5G vehicle-to-everything (V2X) terminal under test in real time during the test. After the test is completed, the data is compared with the communication performance benchmark value, the degree of performance degradation is calculated, and the radio frequency immunity assessment result of the 5G V2X terminal under test is output.

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