Test and fault diagnosis method and device for navigation management responder and airborne collision avoidance system

Abstract

The invention relates to the technical field of testing and fault diagnosis, in particular to a testing and fault diagnosis method and device for a navigation management responder and an airborne collision avoidance system, and the method comprises the steps: constructing a fault case library and an expert knowledge library, and testing the navigation management responder and the airborne collision avoidance system, acquiring test results and characteristic parameters of the navigation management responder and the airborne collision avoidance system; if the test result does not meet the preset standard, matching the feature parameters with fault cases in an expert knowledge base through an inference engine, and outputting fault causes and processing suggestions according to requirements; according to the technical scheme, by integrating the automatic test system and the fault diagnosis reasoning system, various performance tests of the navigation management responder and the airborne collision avoidance system can be automatically executed, and the test efficiency and precision are remarkably improved.

Description

Technical Field

[0001] The present invention relates to the technical field of testing and fault diagnosis, and in particular to a testing and fault diagnosis method and device for an air traffic control transponder and an airborne collision avoidance system. Background Art

[0002] The air traffic control transponder (XPDR) and the airborne collision avoidance system (ACAS) are crucial systems for aircraft flight safety. The air traffic control transponder provides aircraft positioning information to air traffic control by receiving interrogation signals from air traffic control radars and transmitting flight information back. The airborne collision avoidance system calculates potential collision risks by monitoring the flight environment around the aircraft and issues warnings or takes automatic avoidance measures when necessary. The normal operation of these systems is crucial to ensuring flight safety. Therefore, regular testing and fault diagnosis are important parts of aviation maintenance work.

[0003] An expert system is a computer software application system that can simulate the thinking mode of human experts to solve problems in specific fields. An expert system consists of a knowledge base and an inference engine. The knowledge base is the knowledge and experience of experts in a specific field, and the inference engine is the process of simulating the reasoning and judgment of human experts. To solve complex problems in certain fields, human experts' knowledge and problem analysis logic can be used to make inferences, make decisions and solve problems.

[0004] At present, there are mainly the following ways to test air traffic control transponders and ACAS: one is to test through general instruments such as vector signal source, spectrum analyzer, real-time signal analyzer, etc.; the second is to directly use professional transponder testing equipment, such as IFR6000, ATC5000NG, RGS2000NG, etc.; the third is to use a special signal simulator, that is, to simulate the excitation signal of the air traffic control transponder and ACAS, and obtain the indicators of the air traffic control transponder and ACAS transmission signal through down-conversion, AD sampling, signal processing, etc.

[0005] The above methods can all achieve the purpose of testing whether the air traffic control transponder and ACAS functions are intact, but the above test instruments themselves cannot analyze the results, and cannot locate and diagnose air traffic control transponder and ACAS faults. Summary of the invention

[0006] The technical problem to be solved by the present invention is that the existing test methods for air traffic control transponders and airborne collision avoidance systems lack efficient and intelligent automated testing and fault diagnosis means, and are unable to quickly and accurately locate the cause of the fault and provide effective processing suggestions. The purpose is to provide a test and fault diagnosis method and device for air traffic control transponders and airborne collision avoidance systems. By combining an automated test system with a fault diagnosis and reasoning system, automated performance testing, fault diagnosis and elimination suggestion generation are achieved, thereby achieving efficient and accurate fault diagnosis, shortening maintenance time and improving flight safety.

[0007] The present invention is achieved through the following technical solutions:

[0008] A method for testing and diagnosing faults of an air traffic control transponder and an airborne collision avoidance system, comprising:

[0009] Based on the fault tree analysis method, the fault tree model of the air traffic control transponder and the airborne collision avoidance system is established, and a fault case library is built based on real troubleshooting experience;

[0010] Use IF-THEN production rules to transform fault tree models and fault cases into expert knowledge base;

[0011] Based on the standard requirements of the air traffic control transponder and the airborne collision avoidance system, the air traffic control transponder and the airborne collision avoidance system are tested by an automated test system to obtain the test results and characteristic parameters of the air traffic control transponder and the airborne collision avoidance system; the automated test system is used to test multiple performance indicators of the air traffic control transponder and the airborne collision avoidance system;

[0012] If the test results do not meet the preset standards, the inference engine will match the characteristic parameters with the fault cases in the expert knowledge base, and output the fault cause and handling suggestions as required.

[0013] Specifically, the method of building a fault case library includes:

[0014] Conduct a systematic analysis of the functions and performance indicators of the air traffic control transponder and airborne collision avoidance system, and establish a fault tree structure based on potential fault causes;

[0015] Combined with the actual troubleshooting experience accumulated during the design, production and maintenance of air traffic control transponders and airborne collision avoidance systems, a fault case library is constructed, which includes common fault types, possible fault causes and corresponding troubleshooting methods.

[0016] Specifically, the method of constructing the expert knowledge base includes:

[0017] Based on the fault types and possible fault causes defined in the fault tree model, corresponding IF-THEN rules are created to construct a knowledge expression model G(F)=T(f1θ1, f2θ2,…, f n θn ), where F is a certain fault type, G(F) is a possible fault cause, f is a characteristic parameter of the test result, θ is an influencing factor, n is the total number of features, and T is an IF-THEN rule, which includes specific fault phenomena, possible causes, and corresponding treatment measures;

[0018] The condition part of the IF-THEN rule describes the measured value or state of the fault parameter, and the conclusion part describes the possible fault cause and solution.

[0019] Specifically, the features of the air traffic control transponder tested by the automated test system include: transmission power, transmission frequency, receiving sensitivity and sensitivity difference of mode A and mode C interrogation signals, receiving sensitivity of mode S interrogation signals, whether DF17 broadcast is available, F1 / F2 pulse width and interval of mode A and C reply signals, reply delay of mode A and C replies, reply jitter of mode A and C replies, reply rate of mode A and C, pulse amplitude variation of mode A and C replies, mode S reply delay, mode S reply jitter, mode S reply pulse width, mode S reply pulse spacing, altitude code, 3 / A code, and mode S address;

[0020] The features of the airborne collision avoidance system tested by the automated test system include: transmit power, transmit frequency, receive sensitivity, whisper call inquiry period, S1 pulse width and amplitude, P1 pulse width and amplitude, P3 pulse width and amplitude, UF16 broadcast period, RA broadcast period, traffic advisory warning time and indication, and decision advisory warning time and indication;

[0021] Different test case templates are constructed based on different test characteristics. The templates include input parameters, output expectations, test conditions and result judgment criteria. The result judgment criteria are set based on standard requirements.

[0022] Specifically, if the test result does not match the output expectation, a matching is performed through the inference engine, and the method includes:

[0023] The characteristic parameters represented by the test results are matched with the fault cases in the expert knowledge base. The matching process calculates the similarity based on the Pearson correlation coefficient and the Euclidean distance. Among them, X is the feature parameter vector represented by the current test result, Y is the feature vector in the fault case, n is the number of feature parameters, P(X, Y) is the case similarity between X and Y, and x i is the value of the i-th characteristic parameter in the current test result, y i is the value of the i-th characteristic parameter in the fault case, is the mean value of all characteristic parameters in the current test result, is the mean of all characteristic parameters in the fault case;

[0024] Sort the similarities in descending order, and output the fault causes and handling suggestions corresponding to the first A fault cases in the queue as required.

[0025] Optionally, the fault causes include: failure to provide normal radio altitude data, failure to provide normal atmospheric machine data, receiving channel failure, transmitting channel failure, signal processing board failure, radio frequency front end failure;

[0026] The processing suggestions include: it is recommended to perform a continuity test on the device cable, it is recommended to check the host socket, it is recommended to check the internal wiring of the host, it is recommended to check whether the device and the power supply are grounded, it is recommended to replace the RF cable and retest, it is recommended to replace the device antenna and retest, it is recommended to retest after powering off, and it is recommended to check the control box parameter settings.

[0027] A test and fault diagnosis device for an air traffic control transponder and an airborne collision avoidance system, used to perform the test and fault diagnosis method for an air traffic control transponder and an airborne collision avoidance system as described above, the device comprising an automated test system and a fault diagnosis reasoning system, the automated test system being used to test multiple performance indicators of the air traffic control transponder and the airborne collision avoidance system;

[0028] The fault diagnosis reasoning system includes: an expert knowledge base and a reasoning engine, wherein the reasoning engine is in communication connection with the expert knowledge base; and is used to provide fault causes and processing suggestions based on test results;

[0029] The automated test system comprises: a single board computer, a digital signal processing module, a radio frequency front end module and a test case module, wherein the radio frequency front end module, the digital signal processing module and the inference engine are electrically connected to the single board computer module;

[0030] The test case module is used to construct different test case templates according to the standard requirements of the air traffic control transponder and the airborne collision avoidance system, automatically execute the test and obtain the test results, and run on the single board computer;

[0031] The radio frequency front-end module and the digital signal processing module are used to connect the device under test and the test case template.

[0032] Furthermore, the system also includes a human-computer interaction interface, which is used to interact with the user and provide test parameter settings, test case selection, test result display, fault causes and processing suggestions for the air traffic control transponder and the airborne collision avoidance system;

[0033] The human-computer interaction interface is communicatively connected with the automated testing system and the fault diagnosis and reasoning system.

[0034] Specifically, the digital signal processing module includes:

[0035] A radio frequency input unit, used for directly inputting radio frequency signals and converting them into digital signals;

[0036] A digital signal processing unit is used to process the received digital signal, complete the modulation of the XPDR, ACAS interrogation and reply signals, and generate a radio frequency signal;

[0037] The video signal generation unit is used to generate and restore the received or transmitted video signal through ZYNQ and DAC, generate the synchronization signal in real time, and output it to the test case module;

[0038] The digital signal processing module is connected to the single-board computer via a PCIe communication interface for transmitting processing results and characteristic parameters.

[0039] Specifically, the RF front-end module includes:

[0040] The transmitting branch is used to attenuate the modulated RF input excitation signal and output it to the receiving device in the direct mode; in the wireless mode, the transmitting branch attenuates the modulated RF input excitation signal and transmits it through the antenna interface;

[0041] The receiving branch is used to provide the input level RF signal to the digital signal processing module after attenuation in the pass-through mode; in the wireless mode, the receiving branch provides the input level RF signal to the digital signal processing module after attenuation;

[0042] The transmitting branch and the receiving branch work together during the transmission and reception of radio frequency signals.

[0043] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0044] The present invention establishes a fault tree model of an air traffic control transponder and an airborne collision avoidance system through a fault tree analysis method, and constructs a fault case library in combination with real troubleshooting experience; then, the fault tree model and the fault case are converted into an expert knowledge base using IF-THEN production rules; through an automated testing system, multiple performance indicators of the air traffic control transponder and the airborne collision avoidance system are tested to obtain test results and characteristic parameters; if the test results do not meet the preset standards, the inference engine matches the characteristic parameters with the fault cases in the expert knowledge base, and outputs the fault cause and processing suggestions based on the similarity calculation.

[0045] The technical solution of the present invention can automatically perform various performance tests of air traffic control transponders and airborne collision avoidance systems by integrating an automated test system and a fault diagnosis and reasoning system, significantly improving the efficiency and accuracy of the test. By automatically generating and executing test case templates, manual intervention is reduced and human operation errors are avoided. The reasoning engine provides fault analysis and troubleshooting suggestions based on the expert knowledge base, quickly and accurately locates the cause of the fault and guides maintenance personnel to perform effective repairs, reducing diagnosis time and improving maintenance efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] The accompanying drawings illustrate exemplary embodiments of the present invention and, together with the description thereof, are used to explain the principles of the present invention. These drawings are included to provide a further understanding of the present invention, and the accompanying drawings are included in and constitute a part of this specification and do not constitute a limitation of the embodiments of the present invention.

[0047] Figure 1 It is a flow chart of a method for testing and diagnosing faults of an air traffic control transponder and an airborne collision avoidance system according to the present invention.

[0048] Figure 2 It is a test case flow chart according to the present invention.

[0049] Figure 3 The present invention is a block diagram of the working principle of a device for testing and diagnosing faults of an air traffic control transponder and an airborne collision avoidance system. DETAILED DESCRIPTION

[0050] To make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and implementation methods. It is understood that the specific implementation methods described herein are only used to explain the relevant content, rather than to limit the present invention.

[0051] It should also be noted that, for the convenience of description, only the parts related to the present invention are shown in the drawings.

[0052] In the absence of conflict, the embodiments and features of the embodiments of the present invention may be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0053] Embodiment 1

[0054] like Figure 1 As shown, a method for testing and diagnosing faults of an air traffic control transponder and an airborne collision avoidance system comprises:

[0055] Based on the fault tree analysis method, a fault tree model of the air traffic control transponder and airborne collision avoidance system is established, and a fault case library is built in combination with real troubleshooting experience; the fault tree analysis method (FTA) is usually used to identify potential causes of failures in the system. By performing logical analysis on each functional module of the system, it can help build a hierarchical fault tree model. This model starts from the top-level fault of the system and gradually decomposes downward until the most basic fault event. The fault case library brings together various types of faults that occur during the design, production and maintenance of air traffic control transponders and airborne collision avoidance systems, as well as their corresponding causes and solutions.

[0056] The fault tree model and fault cases are converted into an expert knowledge base using IF-THEN production rules; IF-THEN rules are applied to expert systems, and their basic form is: if (IF) certain conditions are met, then (THEN) a conclusion is drawn or an action is performed. These rules simulate the thinking process of human experts and judge the cause of the fault based on historical fault cases and experience.

[0057] Based on the standard requirements of air traffic control transponders and airborne collision avoidance systems, the air traffic control transponders and airborne collision avoidance systems are tested through an automated test system to obtain test results and characteristic parameters of the air traffic control transponders and airborne collision avoidance systems; the automated test system is used to test multiple performance indicators of air traffic control transponders and airborne collision avoidance systems; the automated test system automatically tests various performance indicators of air traffic control transponders and airborne collision avoidance systems by executing preset test case templates. Test items include multiple performance indicators such as transmit power, receive sensitivity, response rate, pulse width, etc. The test system can collect test data in real time and generate test results and characteristic parameters according to standard requirements.

[0058] If the test results do not meet the preset standards, the inference engine will match the characteristic parameters with the fault cases in the expert knowledge base, and output the fault cause and handling suggestions as required.

[0059] The inference engine can infer based on the rule base (in this embodiment, the expert knowledge base) and the input data to draw possible conclusions; the inference engine receives the characteristic parameters in the test results, uses the fault case matching algorithm in the expert knowledge base to compare, and finds the fault case that is most similar to the test results. The inference engine uses the Pearson correlation coefficient and Euclidean distance algorithms to measure the similarity between the current test data and the fault case. The Pearson correlation coefficient is mainly used to determine the linear correlation between two data sets, while the Euclidean distance measures the "distance" between data points. Through these two algorithms, the inference engine can accurately match fault cases and give relevant fault causes and troubleshooting suggestions.

[0060] Embodiment 2

[0061] Methods for building a fault case library include:

[0062] A systematic analysis of the functions and performance indicators of the air traffic control transponder and the airborne collision avoidance system is carried out. Through a comprehensive analysis of the working principles and functions of the air traffic control transponder (XPDR) and the airborne collision avoidance system (ACAS), the possible failure risks of each functional module are identified. For example, the functions of the air traffic control transponder include signal reception, signal transmission and response, while the airborne collision avoidance system includes detecting the surrounding environment, calculating the collision risk and issuing warnings. These functions have various potential failure points during normal operation, such as substandard receiving sensitivity and excessive response delay.

[0063] A fault tree structure is established based on the potential causes of failures; a fault tree model is constructed by decomposing the potential causes of failures of each functional module layer by layer. The top layer of the fault tree represents the system-level failure, and the branches of the tree represent the possible causes of the failure.

[0064] Combined with the real troubleshooting experience accumulated during the design, production and maintenance of air traffic control transponders and airborne collision avoidance systems, a fault case library is built. The fault case library includes common fault types, possible fault causes and corresponding troubleshooting methods. By continuously updating the case library, the system can reflect the common failure modes of the equipment in actual use.

[0065] Methods for constructing an expert knowledge base include:

[0066] Based on the fault types and possible fault causes defined in the fault tree model, corresponding IF-THEN rules are created. For example, when a characteristic parameter (such as the response delay of the transponder) is detected to exceed the preset threshold, the system can determine the possible fault type (such as the signal processing failure of the transponder) through rule reasoning.

[0067] Construct the knowledge representation model G(F)=T(f1θ1,f2θ2,…,f n θ n ), where F is a certain fault type, G(F) is a possible fault cause, f is a characteristic parameter of the test result, θ is an influencing factor, n is the total number of features, and T is an IF-THEN rule, which includes specific fault phenomena, possible causes, and corresponding treatment measures;

[0068] The condition part of the IF-THEN rule describes the measurement value or state of the fault parameter, such as "if the answer rate of the transponder is below a certain threshold." The conclusion part describes the possible cause of the fault and the solution, such as "if the answer rate is low, it may be due to a fault in the RF front-end module, and the antenna connection should be checked."

[0069] Embodiment 3

[0070] Multiple performance indicators of the air traffic control transponder and airborne collision avoidance system are tested through an automated test system, and different test case templates are constructed based on different test characteristics, including the detection of multiple key performance indicators such as the transmission power, receiving sensitivity, and response signal of the air traffic control transponder and airborne collision avoidance system.

[0071] The features of the ATC transponder tested by the automated test system include: transmit power, transmit frequency, receiving sensitivity and sensitivity difference of mode A and mode C interrogation signals, receiving sensitivity of mode S interrogation signals, whether DF17 broadcast is available, F1 / F2 pulse width and interval of mode A and C reply signals, reply delay of mode A and C replies, reply jitter of mode A and C replies, reply rate of mode A and C, pulse amplitude variation of mode A and C replies, mode S reply delay, mode S reply jitter, mode S reply pulse width, mode S reply pulse spacing, altitude code, 3 / A code, and mode S address;

[0072] The features of the airborne collision avoidance system tested by the automated test system include: transmit power, transmit frequency, receive sensitivity, whisper call inquiry period, S1 pulse width and amplitude, P1 pulse width and amplitude, P3 pulse width and amplitude, UF16 broadcast period, RA broadcast period, traffic advisory warning time and indication, and decision advisory warning time and indication;

[0073] Different test case templates are constructed based on different test characteristics. The templates include input parameters, output expectations, test conditions and result judgment criteria. The result judgment criteria are set based on standard requirements.

[0074] Input parameters: such as transmission power, frequency, number of inquiries, etc.

[0075] Output expectations: such as response rate, delay time, etc.

[0076] Test conditions: the setting conditions of the test equipment to ensure a consistent test environment;

[0077] Result judgment standard: The test result qualification standard set according to the standard requirements.

[0078] like Figure 2 As shown, the test cases of the response rates of modes A and C of this embodiment are described. In the test of the response rates of modes A and C, the antenna port of the transponder is connected to the test device through a radio frequency cable. The test device sets the parameters such as the transmission power, frequency, and number of inquiries, and uses the software radio module to generate and transmit the secondary radar standard mode A and mode C interrogation signals. The test system receives and parses the response of the transponder to determine whether the response signal meets the set standard. By comparing the test results with the expected value, the response rate is calculated and output.

[0079] The specific steps include: connecting the antenna port on the transponder and the test device through an RF cable - setting the test device transmission power to the transponder receiving sensitivity + 6dB, the transmission frequency to 1030MHz, the number of inquiries to 500 times / s, and generating and transmitting the secondary radar standard mode A inquiry signal through the software radio module - receiving and analyzing the mode A response signal of the transponder, and judging whether the 3 / A code is consistent with the code set by the control box; if consistent, counting the number of responses, calculating and outputting the response rate - setting the test device transmission power to the transponder receiving sensitivity + 6dB, the transmission frequency to 1030MHz, the number of inquiries to 500 times / s, and generating and transmitting the secondary radar standard mode C inquiry signal through the software radio module - receiving and analyzing the mode C response signal of the transponder, and judging whether the altitude code is consistent with the set altitude; if consistent, counting the number of responses, and calculating Calculate and output the response rate - Set the test device transmission power to -81dBm, the transmission frequency to 1030MHz, the number of inquiries to 500 times / s, and generate and transmit the secondary radar standard mode A interrogation signal through the software radio module - Receive the mode A response signal of the parsing transponder, and determine whether the 3 / A code is consistent with the code set in the control box; if consistent, count the number of responses, calculate and output the response rate - Set the test device transmission power to -81dBm, the transmission frequency to 1030MHz, the number of inquiries to 500 times / s, and generate and transmit the secondary radar standard mode C interrogation signal through the software radio module - Receive the mode C response signal of the parsing transponder, and determine whether the altitude code is consistent with the set altitude; if consistent, count the number of responses, calculate and output the response rate - Repeat the above steps to measure the characteristic parameters of the antenna port below the transponder.

[0080] Embodiment 4

[0081] In this embodiment, the inference engine can automatically perform fault diagnosis and give fault causes and treatment suggestions when the test results do not match the expected output. The process uses the Pearson correlation coefficient and Euclidean distance to calculate similarity, thereby matching the current test results with the fault cases in the expert knowledge base.

[0082] If the test result does not match the output expectation, the inference engine is used to match it. The methods include:

[0083] The characteristic parameters represented by the test results are matched with the fault cases in the expert knowledge base. The matching process calculates the similarity based on the Pearson correlation coefficient and the Euclidean distance. The Pearson correlation coefficient can measure the strength of the linear relationship between two vectors. The larger the value, the stronger the correlation between the two vectors.

[0084] Among them, X is the feature parameter vector represented by the current test result, Y is the feature vector in the fault case, n is the number of feature parameters, P(X, Y) is the case similarity between X and Y, and x i is the value of the i-th characteristic parameter in the current test result, y i is the value of the i-th characteristic parameter in the fault case, is the mean value of all characteristic parameters in the current test result, is the mean of all characteristic parameters in the fault case;

[0085] Sort the similarities in descending order, and output the fault causes and handling suggestions corresponding to the first A fault cases in the queue as required. A is determined according to the specific situation. If only the most likely fix needs to be output, A=1; if more possible faults need to be output, A can be set equal to other numbers.

[0086] After reasoning from the expert knowledge base, the possible causes of failure and suggestions given mainly include: failure to provide normal radio altitude data, failure to provide normal atmospheric machine data, receiving channel failure, transmitting channel failure, signal processing board failure, and RF front-end failure; it is recommended to perform a continuity test on the device cable, check the host socket, check the internal wiring of the host, check whether the device and the power supply are grounded, replace the RF cable and retest, replace the device antenna and retest, retest after power off, and check the control box parameter settings.

[0087] Embodiment 5

[0088] Take a certain type of transponder as the test object, connect it directly to the test device through a radio frequency cable, select the type of transponder as ATCRBS in the human-computer interaction interface, and then click to start the test. The test device will automatically call the following test cases to test the ATCRBS transponder.

[0089] 1) A / C mode decoding test;

[0090] 2) Sidelobe suppression test;

[0091] 3) A code test;

[0092] 4) C code testing;

[0093] 5) F1 / F2 pulse width and interval of mode A and C response signals;

[0094] 6) Response delay for Mode A and C responses;

[0095] 7) Response jitter of Mode A and C responses;

[0096] 8) Response rates of modes A and C;

[0097] 9) Mode A and C responses to ATCRBS all-call interrogations;

[0098] 10) Mode A and C response pulse amplitude changes;

[0099] 11) Transmitting frequency test;

[0100] 12) Transmitted power (ERP) test;

[0101] 13) Sensitivity test;

[0102] 14) A / C mode sensitivity difference.

[0103] The detailed description of the response rate test cases of Mode A and C is as follows: Figure 1 shown.

[0104] After testing, the characteristic parameters of the transponder are obtained:

[0105] 1) Mode A inquiry, the response rate when the P1-P3 interval is 8.2us is 88.7%

[0106] 2) Mode C inquiry, the response rate when the P1-P3 interval is 21.2us is 88.1%

[0107] 3) Mode A inquiry, the response rate when the P1-P3 interval is 7.8us is 88.4%

[0108] 4) Mode C inquiry, the response rate is 88.5% when the P1-P3 interval is 20.8us

[0109] 5) Mode A inquiry, the response rate is 0 when the P1-P3 interval is 9us

[0110] 6) Mode C inquiry, the response rate is 0 when the P1-P3 interval is 22us

[0111] 7) Mode A inquiry, the response rate is 0 when the P1-P3 interval is 7us

[0112] 8) Mode C inquiry, the response rate is 0 when the interval between P1 and P3 is 20us

[0113] 9) Mode A inquiry, the relative amplitude of SLS and P1 pulses is -9dB, and the response rate is 88.5%

[0114] 10) Mode C interrogation, the response rate of the relative amplitude of SLS and P1 pulses is -9dB is 88.3%

[0115] 11) Mode A inquiry, the response rate is 0 when the relative amplitude of SLS and P1 pulses is 0dB

[0116] 12) Mode C inquiry, the response rate is 0 when the relative amplitude of SLS and P1 pulses is 0dB

[0117] 13)3 / A code verification is True

[0118] 14) Flight altitude verification is True

[0119] 15) F1 pulse width is 0.431us

[0120] 16) F2 pulse width is 0.438us

[0121] 17) The F1-F2 pulse interval is 20.305us

[0122] 18) Mode A inquiry, the response delay time is 2.59us

[0123] 19) Mode C inquiry, response delay time is 2.88us

[0124] 20) Mode A inquiry, the jitter of the response delay time is 0.018us

[0125] 21) Mode C inquiry, the jitter of the response delay time is 0.018us

[0126] 22) Power is -67dBm, Mode A inquiry response rate is 88.5%

[0127] 23) The power is -67dBm, and the response rate of mode C inquiry is 88.3%

[0128] 24) Power is -81dBm, Mode A inquiry response rate is 38%

[0129] 25) Power is -81dBm, Mode C inquiry response rate is 42%

[0130] 26) The maximum deviation of the response pulse amplitude in mode A is 0.3dB

[0131] 27) The maximum deviation of the response pulse amplitude in mode C is 0.3dB

[0132] 28) The transmission frequency of the transponder is 1090.02MHz

[0133] 29) The ERP of the answering machine is 53.9dBm

[0134] 30) Mode A interrogation, the transponder sensitivity is -65dBm

[0135] 31) Mode C interrogation, transponder sensitivity -65dBm

[0136] The feature parameters are input into the inference engine, the case similarity matching value is calculated, and the fault analysis and processing suggestions of the most similar fault cases in the expert knowledge base are output to the human-computer interaction interface.

[0137] The human-computer interaction interface of the test device displays:

[0138] Possible cause of failure: transponder receiver failure.

[0139] Troubleshooting suggestions:

[0140] 1) Replace the transponder connector and cable and retest;

[0141] 2) If the fault persists after replacement, check the attenuation value of the RF front-end circuit, and whether the resistance and voltage of the components are normal;

[0142] 3) If there is no problem with the RF front-end circuit, the receiver performance may be degraded. Replace the transponder receiver module and test again.

[0143] Embodiment 6

[0144] like Figure 2 As shown, a test and fault diagnosis device for an air traffic control transponder and an airborne collision avoidance system is provided, which is used to perform a test and fault diagnosis method for an air traffic control transponder and an airborne collision avoidance system as described above, and the device includes an automated test system and a fault diagnosis reasoning system, and the automated test system is used to test multiple performance indicators of the air traffic control transponder and the airborne collision avoidance system;

[0145] The fault diagnosis reasoning system includes: an expert knowledge base and a reasoning engine, which are connected to the expert knowledge base in communication; and is used to provide fault causes and processing suggestions based on test results;

[0146] The automated test system comprises: a single board computer, a digital signal processing module, a radio frequency front end module and a test case module, wherein the radio frequency front end module, the digital signal processing module and the inference engine are electrically connected to the single board computer module;

[0147] The test case module is used to build different test case templates according to the standard requirements of air traffic control transponders and airborne collision avoidance systems, automatically execute tests and obtain test results, and runs on a single-board computer;

[0148] The RF front-end module and the digital signal processing module are used to connect the device under test and the test case template.

[0149] The system also includes a human-computer interaction interface, which is used to interact with the user and provide test parameter settings, test case selection, test result display, fault causes and processing suggestions for the air traffic control transponder and airborne collision avoidance system;

[0150] The human-computer interaction interface communicates with the automated test system and the fault diagnosis and reasoning system. The development of the human-computer interaction interface is based on QT, providing users with the functions of setting test parameters required for XPDR and ACAS tests, selecting test cases, displaying test results, fault analysis, and displaying troubleshooting suggestions.

[0151] Single-board computer: Adlink Technology's mini COM Express series computing module is selected, which has low power consumption, light weight and small size. It is used as a platform to support the operation of the software part and provide bus interfaces for other modules. It also supports the universal high-speed bus PCIe interface to realize data transmission between software and software radio modules.

[0152] Digital signal processing module: The analog-to-digital and digital-to-analog conversion of the data processing part is realized by direct RF acquisition and output, using the RF transceiver chip AD9361. After being processed, the RF signal directly enters the input end of AD9361. After data processing is completed, the RF signal output is directly generated. The video signal is generated by ZYNQ and DAC, and the received video or transmitted video signal is restored. The synchronization signal directly enters the PL end of ZYNQ, which is convenient for real-time generation of synchronization signals. Complete the modulation of XPDR, ACAS inquiry and response signals, that is, ASK, DPSK, PPM encoding and other algorithms to generate RF signals; collect RF signals and generate zero intermediate frequency sampling signals to complete the demodulation and measurement of XPDR and ACAS signals; provide a PCIe communication interface between the digital processing module and the computer board. The module includes:

[0153] A radio frequency input unit, used for directly inputting radio frequency signals and converting them into digital signals;

[0154] A digital signal processing unit is used to process the received digital signal, complete the modulation of the XPDR, ACAS interrogation and reply signals, and generate a radio frequency signal;

[0155] The video signal generation unit is used to generate and restore the received or transmitted video signal through ZYNQ and DAC, generate the synchronization signal in real time, and output it to the test case module;

[0156] The digital signal processing module is connected to the single board computer through a PCIe communication interface for transmitting processing results and characteristic parameters.

[0157] The RF front-end module is mainly composed of a transmitting branch and a receiving branch. In the pass-through mode, the main function of the transmitting branch is to attenuate the modulated RF input excitation signal to -115dBm~-47dBm output, and the receiving branch is to attenuate the input level of +43dBm~+66dBm to -40dBm~0dBm, and provide it to the digital-analog processing chip AD9361. In the wireless mode, the main function of the transmitting branch is to attenuate the modulated RF input excitation signal to -67dBm~-2dBm and transmit it through the antenna interface, and the receiving branch is to attenuate the input level of +40dBm to -40dBm~0dBm. The module includes:

[0158] The transmitting branch is used to attenuate the modulated RF input excitation signal and output it to the receiving device in the direct mode; in the wireless mode, the transmitting branch attenuates the modulated RF input excitation signal and transmits it through the antenna interface;

[0159] The receiving branch is used to provide the input level RF signal to the digital signal processing module after attenuation in the pass-through mode; in the wireless mode, the receiving branch provides the input level RF signal to the digital signal processing module after attenuation;

[0160] The transmitting branch and the receiving branch work together during the transmission and reception of radio frequency signals.

[0161] In the description of this specification, the description with reference to the terms "one embodiment / method", "some embodiments / methods", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment / method or example are included in at least one embodiment / method or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment / method or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments / methods or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments / methods or examples described in this specification and the features of the different embodiments / methods or examples, unless they are contradictory.

[0162] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of this application, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0163] It should be understood by those skilled in the art that the above embodiments are only for the purpose of clearly illustrating the present invention, and are not intended to limit the scope of the present invention. For those skilled in the art, other changes or modifications may be made based on the above invention, and these changes or modifications are still within the scope of the present invention.

Claims

1. A method for testing and diagnosing faults of air traffic control transponders and airborne collision avoidance systems, characterized in that: include: Based on the fault tree analysis method, the fault tree model of the air traffic control transponder and the airborne collision avoidance system is established, and a fault case library is built based on real troubleshooting experience; Use IF-THEN production rules to transform fault tree models and fault cases into expert knowledge base; Based on the standard requirements of the air traffic control transponder and the airborne collision avoidance system, the air traffic control transponder and the airborne collision avoidance system are tested by an automated test system to obtain the test results and characteristic parameters of the air traffic control transponder and the airborne collision avoidance system; the automated test system is used to test multiple performance indicators of the air traffic control transponder and the airborne collision avoidance system; If the test results do not meet the preset standards, the inference engine will match the characteristic parameters with the fault cases in the expert knowledge base, and output the fault cause and handling suggestions as required.

2. The method for testing and diagnosing faults of an air traffic control transponder and an airborne collision avoidance system according to claim 1, characterized in that: Methods for building a fault case library include: Conduct a systematic analysis of the functions and performance indicators of the air traffic control transponder and airborne collision avoidance system, and establish a fault tree structure based on potential fault causes; Combined with the actual troubleshooting experience accumulated during the design, production and maintenance of air traffic control transponders and airborne collision avoidance systems, a fault case library is constructed, which includes common fault types, possible fault causes and corresponding troubleshooting methods.

3. The method for testing and diagnosing faults of an air traffic control transponder and an airborne collision avoidance system according to claim 1, characterized in that: Methods for constructing an expert knowledge base include: Based on the fault types and possible fault causes defined in the fault tree model, corresponding IF-THEN rules are created to construct a knowledge expression model G(F)=T(f1θ1, f2θ2,…, f n θ n ), where F is a certain fault type, G(F) is the possible fault cause, f is the characteristic parameter of the test result, θ is the influencing factor, n is the total number of features, T is the IF-THEN rule, and the rule includes the specific fault phenomenon, possible causes and corresponding treatment measures; The condition part of the IF-THEN rule describes the measured value or state of the fault parameter, and the conclusion part describes the possible fault cause and solution.

4. The method for testing and diagnosing faults of an air traffic control transponder and an airborne collision avoidance system according to claim 1, characterized in that: The features of the ATC transponder tested by the automated test system include: transmit power, transmit frequency, receiving sensitivity and sensitivity difference of mode A and mode C interrogation signals, receiving sensitivity of mode S interrogation signals, whether DF17 broadcast is available, F1 / F2 pulse width and interval of mode A and C reply signals, reply delay of mode A and C replies, reply jitter of mode A and C replies, reply rate of mode A and C, pulse amplitude variation of mode A and C replies, mode S reply delay, mode S reply jitter, mode S reply pulse width, mode S reply pulse spacing, altitude code, 3 / A code, and mode S address; The features of the airborne collision avoidance system tested by the automated test system include: transmit power, transmit frequency, receive sensitivity, whisper call inquiry period, S1 pulse width and amplitude, P1 pulse width and amplitude, P3 pulse width and amplitude, UF16 broadcast period, RA broadcast period, traffic advisory warning time and indication, and decision advisory warning time and indication; Different test case templates are constructed based on different test characteristics. The templates include input parameters, output expectations, test conditions and result judgment criteria. The result judgment criteria are set based on standard requirements.

5. The method for testing and diagnosing faults of an air traffic control transponder and an airborne collision avoidance system according to claim 4, characterized in that: If the test result does not match the output expectation, the inference engine is used to match it. The methods include: The characteristic parameters represented by the test results are matched with the fault cases in the expert knowledge base. The matching process calculates the similarity based on the Pearson correlation coefficient and the Euclidean distance. Among them, X is the feature parameter vector represented by the current test result, Y is the feature vector in the fault case, n is the number of feature parameters, P(X, Y) is the case similarity between X and Y, and x i is the value of the i-th characteristic parameter in the current test result, y i is the value of the i-th characteristic parameter in the fault case, is the mean value of all characteristic parameters in the current test result, is the mean of all characteristic parameters in the fault case; Sort the similarities in descending order, and output the fault causes and handling suggestions corresponding to the first A fault cases in the queue as required.

6. The method for testing and diagnosing faults of an air traffic control transponder and an airborne collision avoidance system according to claim 1, characterized in that: The causes of the failure include: failure to provide normal radio altitude data, failure to provide normal atmospheric machine data, receiving channel failure, transmitting channel failure, signal processing board failure, and RF front-end failure; The processing suggestions include: it is recommended to perform a continuity test on the device cable, it is recommended to check the host socket, it is recommended to check the internal wiring of the host, it is recommended to check whether the device and the power supply are grounded, it is recommended to replace the RF cable and retest, it is recommended to replace the device antenna and retest, it is recommended to retest after powering off, and it is recommended to check the control box parameter settings.

7. A testing and fault diagnosis device for air traffic control transponders and airborne collision avoidance systems, characterized in that: Used to perform a test and fault diagnosis method for an air traffic control transponder and an airborne collision avoidance system as described in any one of claims 1 to 6, the device includes an automated test system and a fault diagnosis and reasoning system, the automated test system is used to test multiple performance indicators of the air traffic control transponder and the airborne collision avoidance system; The fault diagnosis reasoning system includes: an expert knowledge base and a reasoning engine, wherein the reasoning engine is in communication connection with the expert knowledge base; and is used to provide fault causes and processing suggestions based on test results; The automated test system comprises: a single board computer, a digital signal processing module, a radio frequency front end module and a test case module, wherein the radio frequency front end module, the digital signal processing module and the inference engine are electrically connected to the single board computer module; The test case module is used to construct different test case templates according to the standard requirements of the air traffic control transponder and the airborne collision avoidance system, automatically execute the test and obtain the test results, and run on the single board computer; The radio frequency front-end module and the digital signal processing module are used to connect the device under test and the test case template.

8. The device for testing and diagnosing faults of an air traffic control transponder and an airborne collision avoidance system according to claim 7, characterized in that: It also includes a human-computer interaction interface, which is used to interact with the user and provide test parameter settings, test case selection, test result display, fault causes and processing suggestions for the air traffic control transponder and the airborne collision avoidance system; The human-computer interaction interface is communicatively connected with the automated testing system and the fault diagnosis and reasoning system.

9. The testing and fault diagnosis device for air traffic control transponder and airborne collision avoidance system according to claim 7, characterized in that: The digital signal processing module comprises: A radio frequency input unit, used for directly inputting radio frequency signals and converting them into digital signals; A digital signal processing unit is used to process the received digital signal, complete the modulation of the XPDR, ACAS interrogation and reply signals, and generate a radio frequency signal; The video signal generation unit is used to generate and restore the received or transmitted video signal through ZYNQ and DAC, generate the synchronization signal in real time, and output it to the test case module; The digital signal processing module is connected to the single-board computer via a PCIe communication interface for transmitting processing results and characteristic parameters.

10. The testing and fault diagnosis device for air traffic control transponder and airborne collision avoidance system according to claim 7, characterized in that: The radio frequency front-end module comprises: The transmitting branch is used to attenuate the modulated RF input excitation signal and output it to the receiving device in the direct mode; in the wireless mode, the transmitting branch attenuates the modulated RF input excitation signal and transmits it through the antenna interface; The receiving branch is used to provide the input level RF signal to the digital signal processing module after attenuation in the pass-through mode; in the wireless mode, the receiving branch provides the input level RF signal to the digital signal processing module after attenuation; The transmitting branch and the receiving branch work together during the transmission and reception of radio frequency signals.

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