Transponder test method and device and electronic equipment
By filtering and demodulating the original uplink signal of the transponder, the problem of noise and vehicle-passing excitation signals affecting the test results is solved, and a more accurate transponder frequency characteristic test is achieved.
Patent Information
- Application Number
- CN202310952479.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2023-07-31
- Publication Date
- 2025-02-14
AI Technical Summary
The transponder test results are affected by noise and vehicle-passing excitation signals, resulting in inaccurate frequency characteristics test results.
By filtering and demodulating the original uplink signal of the transponder to be tested, the impact of the vehicle excitation signal is reduced, and the demodulation signal is noise filtered, and the center frequency and frequency deviation are calculated to determine whether the transponder has passed the test.
It effectively reduces the impact of noise and vehicle-passing excitation signals on the frequency characteristics of the transponder output signal, and improves the accuracy and reliability of the test.
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Figure CN119449201A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of signal processing, and more specifically, to a transponder testing method, device, and electronic device. Background Art
[0002] The transponder is a ground positioning device installed between the rails in the train control system. It is mainly used to provide the train with fixed ground information (such as line slope, maximum allowable speed, etc.) and variable information. A vehicle-mounted antenna is installed at the bottom of the train. When the train passes the transponder, the vehicle-mounted antenna sends a passing vehicle excitation signal to the transponder. The transponder converts the passing vehicle excitation signal into a working power supply and starts its internal electronic unit, sending an uplink signal (FSK signal) carrying road information to the vehicle-mounted antenna. In order to ensure the consistency of the transponder product and the reliability of its field application, the frequency characteristics of the output signal of the transponder need to be tested before the transponder is put into use to ensure that the transponder meets the test requirements. During the testing process of the transponder, since the output signal of the transponder is transmitted in the propagation medium in the form of electromagnetic waves when receiving the output signal, it is easy to receive noise and passing vehicle excitation signals from the propagation medium while receiving the output signal, resulting in a significant impact on the test results of the frequency characteristics of the output signal of the transponder. Summary of the Invention
[0003] In view of this, the present application provides a transponder testing method, device and electronic device for solving the problem that noise and passing vehicle excitation signals affect transponder test results.
[0004] In order to achieve the above objectives, the following solutions are proposed:
[0005] A transponder testing method, the method comprising:
[0006] generating a vehicle passing excitation signal and sending the vehicle passing excitation signal to the transponder to be tested;
[0007] collecting the original uplink signal output by the transponder to be tested after receiving the vehicle passing excitation signal;
[0008] Filtering and demodulating the original uplink signal to obtain an uplink signal;
[0009] Demodulating the uplink signal to obtain a demodulated signal;
[0010] Processing noise in the demodulated signal;
[0011] Calculating the center frequency and frequency deviation of the filtered original uplink signal by using the filtered original uplink signal and the processed demodulated signal;
[0012] If the center frequency is within a first preset range and the frequency offset is within a second preset range, it is determined that the transponder to be tested has passed the test.
[0013] Optionally, filtering the original uplink signal includes:
[0014] A bandpass filter is used to filter out the vehicle passing excitation signal in the original uplink signal.
[0015] Optionally, performing demodulation preprocessing to obtain an uplink signal includes:
[0016] The uplink signal is obtained by performing phase transformation on the filtered original uplink signal, and the uplink signal differs from the filtered original uplink signal by a preset phase.
[0017] Optionally, the processing noise in the demodulated signal includes:
[0018] Get the standard bit rate of the transponder uplink signal;
[0019] Noise filtering is performed on the demodulated signal using the standard code rate.
[0020] Optionally, generating a vehicle passing excitation signal includes:
[0021] Get a continuous sinusoidal signal with a fixed amplitude;
[0022] The continuous sinusoidal signal is amplitude edited to obtain the vehicle passing excitation signal, which is a signal with three stages: the first stage is the amplitude enhancement stage, the second stage is the amplitude balancing stage, and the third stage is the amplitude reduction stage.
[0023] Optionally, calculating the center frequency and frequency offset of the filtered original uplink signal by using the filtered original uplink signal and the processed demodulated signal includes:
[0024] Determine, according to the processed demodulated signal, a plurality of intervals of the filtered original uplink signal, wherein one interval corresponds to a 0 or a 1 in the processed demodulated signal, the interval corresponding to a 1 is an upper sideband of the filtered original uplink signal, and the interval corresponding to a 0 is a lower sideband of the filtered original uplink signal;
[0025] Selecting a partial interval of the filtered original uplink signal and obtaining an average frequency of an upper sideband and an average frequency of a lower sideband in the partial interval, wherein a total width of the partial interval satisfies a preset bit width;
[0026] The center frequency and frequency deviation of the filtered original uplink signal are calculated according to the average frequency of the upper sideband and the average frequency of the lower sideband.
[0027] Optionally, the calculating the center frequency and the frequency deviation of the filtered original uplink signal by using the average frequency of the upper sideband and the average frequency of the lower sideband includes:
[0028] By formula:
[0029] f1=(f H +f L ) / 2 calculates the center frequency of the original uplink signal after filtering, where f1 is the center frequency, f H is the average probability of the lower sideband, f L is the average probability of the lower sideband;
[0030] By formula:
[0031] f2=(f H -f L ) / 2 calculates the frequency deviation of the original uplink signal after filtering, where f2 is the frequency deviation.
[0032] Optionally, before performing amplitude editing on the continuous sinusoidal signal to obtain the vehicle passing excitation signal, the method further includes:
[0033] Obtaining the instantaneous power of the sinusoidal signal and determining the difference between the instantaneous power and a preset power;
[0034] If the absolute value of the difference is greater than a preset threshold, adjusting the amplitude of the sinusoidal signal until the absolute value of the difference between the instantaneous power and the preset power is less than a preset threshold;
[0035] If the absolute value of the difference between the instantaneous power and the preset power is smaller than a preset threshold, it is confirmed that the transponder test is completed.
[0036] Optionally, also include:
[0037] Recording a first adjustment number and the instantaneous power after each adjustment, wherein the first adjustment number is the number of times the amplitude of the sinusoidal signal is adjusted during the current transponder test;
[0038] When the next transponder test begins, if the difference between the second adjustment number in the next transponder test and the first adjustment number is not less than a preset multiple of the first adjustment number, the preset threshold is adjusted according to the recorded instantaneous power, and the second adjustment number is the number of times the amplitude of the sinusoidal signal is adjusted in the next transponder test.
[0039] A transponder testing device, comprising:
[0040] an excitation signal acquisition unit, configured to generate a vehicle passing excitation signal and send the vehicle passing excitation signal to the transponder to be tested;
[0041] an original uplink signal acquisition unit, configured to acquire the original uplink signal output by the transponder to be tested after receiving the vehicle passing excitation signal;
[0042] an uplink signal acquisition unit, configured to filter and perform demodulation preprocessing on the original uplink signal to obtain an uplink signal;
[0043] A signal demodulation unit, configured to demodulate the uplink signal to obtain a demodulated signal;
[0044] a noise processing unit, configured to process noise in the demodulated signal;
[0045] a data calculation unit, configured to calculate a center frequency and a frequency offset of the filtered original uplink signal by using the filtered original uplink signal and the processed demodulated signal;
[0046] If the center frequency is within a first preset range and the frequency deviation is within a second preset range, triggering a result output unit;
[0047] The result output unit is used to determine whether the transponder to be tested has passed the test.
[0048] This application provides a transponder testing method, apparatus, and electronic device. This method filters the original uplink signal of the transponder under test before demodulating it, reducing the impact of the uplink excitation signal on the original uplink signal. After demodulation, the original uplink signal is subjected to noise filtering to reduce noise introduced by the propagation medium. Consequently, this method can effectively reduce the impact of the passing vehicle excitation signal and the propagation medium on the test results of the frequency characteristics of the transponder's output signal. BRIEF DESCRIPTION OF THE DRAWINGS
[0049] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.
[0050] Figure 1 A flowchart of a transponder testing method provided in an embodiment of the present application;
[0051] Figure 2 A schematic diagram of the structure of an original uplink signal interval after filtering provided in an embodiment of the present application;
[0052] Figure 3 A schematic diagram of the structure of a fixed bit width window provided in an embodiment of the present application;
[0053] Figure 4 A schematic structural diagram of a transponder testing device provided in an embodiment of the present application. DETAILED DESCRIPTION
[0054] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.
[0055] like Figure 1 As shown, an embodiment of the present application provides a transponder testing method, which may include:
[0056] S10: Generate a vehicle passing excitation signal and send the vehicle passing excitation signal to the transponder to be tested.
[0057] The vehicle excitation signal can be a 27.095 MHz sinusoidal signal carrying energy emitted by a vehicle-mounted antenna. Alternatively, the vehicle excitation signal can be obtained directly from the vehicle-mounted antenna or independently generated. The vehicle excitation signal can be transmitted to the transponder under test in the form of electromagnetic waves.
[0058] S11. Collect the original uplink signal output by the balise under test after receiving the vehicle passing excitation signal.
[0059] Since the passing vehicle excitation signal carries energy, after the passing vehicle excitation signal is sent to the transponder under test, the transponder receives the energy in the passing vehicle excitation signal and activates its internal circuit. After the transponder is activated, it transmits the original uplink signal, which can be an FSK signal with a frequency of 4MHz. In this embodiment, when the passing vehicle excitation signal is sent to the transponder, a synchronous trigger signal can be simultaneously sent to the receiving module. After receiving the synchronous trigger signal, the receiving module begins to collect the original uplink signal output by the transponder.
[0060] S12: Filter the original uplink signal and perform demodulation preprocessing to obtain an uplink signal.
[0061] Among them, since in this embodiment, the passing vehicle excitation signal is propagated in the air in the form of electromagnetic waves, the receiving module will inevitably collect a part of the passing vehicle excitation signal when collecting the original uplink signal output by the transponder. Therefore, this embodiment needs to filter the original uplink signal before processing the original uplink signal to reduce the impact of the passing vehicle excitation signal on the original uplink signal. In this embodiment, in order to facilitate the demodulation of the original uplink signal on ordinary equipment, the original uplink signal can be demodulated and pre-processed. Demodulation preprocessing can effectively avoid the use of expensive vector analyzers, improve the diversity of instrument selection and effectively reduce the testing cost of the transponder. The demodulation preprocessing in this embodiment is the Hilbert transform, which can delay the phase of all frequency components of the original signal by 90 degrees.
[0062] S13. Demodulate the uplink signal to obtain a demodulated signal.
[0063] In this embodiment, the signal phase P0 is solved by filtering the original uplink signal and the uplink signal (phase-delayed orthogonal signal) (the phase P0 range is (-P i , +P i ), the phase of the continuous signal will jump at the boundary). In order to avoid the signal jumping at the boundary, the phase P0 is unwound (the phase range is changed from (-P i , +P i ) is extended to (-P i +2×n×P i , +P i +2×n×P i ))Get the phase P1 and determine the phase-cut position to obtain the demodulated signal.
[0064] S14. Process the noise in the demodulated signal.
[0065] There is a lot of noise in the air, such as from base stations, indoor power lines, radiation generated by equipment during operation, and routers. During the acquisition of the original uplink signal, the higher frequency and imperfect impedance matching of the original uplink signal can cause reflections of the high-frequency signal. This reflection also generates some noise, causing signal variations. Therefore, in this embodiment, this noise needs to be processed to reduce its impact on the demodulated signal and, further, its effect on the test results of the transponder's output signal frequency characteristics.
[0066] S15, calculating the center frequency and frequency deviation of the filtered original uplink signal by using the filtered original uplink signal and the processed demodulated signal;
[0067] If the center frequency is within the first preset range and the frequency offset is within the second preset range, executing step S16;
[0068] S16. Determine whether the transponder to be tested passes the test.
[0069] Among them, frequency deviation can refer to the difference between the frequency of the received signal and the frequency of the transmitted signal during the communication process. This embodiment can divide the filtered original uplink signal into multiple regions by demodulating the signal, and use a fixed bit width window to traverse the filtered original uplink signal with a fixed moving bit amount, calculate the center frequency and frequency deviation of each fixed bit width window, and judge whether the center frequency of each fixed bit width window is within the first preset range and whether the frequency deviation is within the second preset range, so as to determine whether the filtered original uplink signal meets the standard of the transponder test, and further determine whether the transponder to be tested meets the standard of the transponder test. The first preset range and the second preset range are the ranges clearly specified in the transponder test standard.
[0070] The present invention provides a transponder testing method that filters the original uplink signal of the transponder under test before demodulating it, reducing the impact of the uplink excitation signal on the original uplink signal. After demodulating the original uplink signal, it is subjected to noise filtering to reduce the noise introduced by the propagation medium. Therefore, this method can effectively reduce the impact of the passing vehicle excitation signal and the propagation medium on the test results of the frequency characteristics of the transponder's output signal.
[0071] According to another transponder testing method provided in an embodiment of the present application, Figure 1 The filtering of the original uplink signal in step S12 may specifically include:
[0072] A bandpass filter is used to filter out the vehicle passing excitation signal in the original uplink signal.
[0073] Among them, in this embodiment, since the passing vehicle excitation signal is a 27.095MHz sinusoidal signal carrying energy, and the original uplink signal is a 4MHz frequency FSK signal carrying information, this embodiment can use a 3MHz to 5MHz low-pass filter to filter out the passing vehicle excitation signal in the original uplink signal, that is, to extract the original uplink signal with a frequency of 4MHz through a low-pass filter.
[0074] According to another transponder testing method provided in an embodiment of the present application, Figure 1 In step S12, demodulation preprocessing is performed to obtain an uplink signal, which may specifically include:
[0075] The filtered original uplink signal is subjected to phase transformation to obtain an uplink signal, and the uplink signal differs from the filtered original uplink signal by a preset phase.
[0076] Among them, the Hilbert transform can have a variety of function transformations, such as sin(ωt) and cos(ωt), the purpose of which is to delay the phase of all frequency components of the original signal by 90 degrees to facilitate subsequent demodulation.
[0077] According to another transponder testing method provided in an embodiment of the present application, Figure 1 Step S14 may include step 1 and step 2:
[0078] Step 1: Obtain the standard bit rate of the transponder uplink signal;
[0079] Step 2: Use the standard bit rate to filter the noise of the demodulated signal.
[0080] The standard code rate of the transponder uplink signal is 564.48 bit / s. This embodiment removes the signals in the demodulated signal that are completely different from 4 MHz in frequency, and performs serial processing on the demodulated signal mainly in combination with the original uplink signal modulation parameters.
[0081] According to another transponder testing method provided in an embodiment of the present application, Figure 1 The generation of the vehicle passing excitation signal in step S14 may include steps three and four:
[0082] Step 3: Obtain a continuous sinusoidal signal with a fixed amplitude;
[0083] Step 4: Perform amplitude editing on the continuous sinusoidal signal to obtain a passing vehicle excitation signal. The passing vehicle excitation signal is a signal with three stages: the first stage is an amplitude enhancement stage, the second stage is an amplitude balancing stage, and the third stage is an amplitude reduction stage.
[0084] Among them, in order to simulate the signal change process when a vehicle passes over the transponder in the embodiment of the present application, the amplitude of the continuous sinusoidal signal with a fixed amplitude is edited to obtain a section of amplitude change signal. Specifically, the amplitude enhancement stage corresponds to the stage when the vehicle-mounted antenna on the vehicle gradually approaches the transponder, the amplitude balance stage corresponds to the stage when the vehicle-mounted antenna on the vehicle is located above the transponder, and the amplitude reduction stage corresponds to the stage when the vehicle-mounted antenna on the vehicle gradually moves away from the transponder. This embodiment can test the transponder by simulating the process of a vehicle passing over the transponder, so that the test results of the transponder are more in line with reality.
[0085] According to another transponder testing method provided in an embodiment of the present application, Figure 1 Step S15 may include steps five to seven:
[0086] Step 5: Determine multiple intervals of the filtered original uplink signal based on the processed demodulated signal, where one interval corresponds to a 0 or a 1 in the processed demodulated signal, one interval corresponding to a 1 is the upper sideband of the filtered original uplink signal, and one interval corresponding to a 0 is the lower sideband of the filtered original uplink signal;
[0087] Step 6: Select a partial interval of the filtered original uplink signal and obtain the average frequency of the upper sideband and the average frequency of the lower sideband in the partial interval, where the total width of the partial interval meets the preset bit width;
[0088] Step 7: Calculate the center frequency and frequency deviation of the filtered original uplink signal using the average frequency of the upper sideband and the average frequency of the lower sideband.
[0089] Among them, such as Figure 2 As shown, signal A is the original uplink signal after filtering, and signal B is the demodulated signal. The demodulated signal can be a baseband signal, and the original uplink signal after filtering can be divided into multiple intervals. 0 or 1 in the demodulated signal corresponds to an interval on the original uplink signal after filtering. The interval corresponding to 1 is C, and the interval corresponding to 0 is D. According to the transponder test specification standard, the original uplink signal after filtering with a duration exceeding 1ms is used to measure the carrier frequency amplitude and phase. Figure 3 As shown, a fixed bit width window a (solid line frame) is set at the starting point of signal A, wherein the fixed bit width adopted in this embodiment is 16 bits. In this embodiment, the center frequency and frequency deviation of the filtered original uplink signal within the fixed bit width window are calculated and it is determined whether the center frequency and frequency deviation at this time meet the standard. After the determination is completed, the fixed bit width window is moved forward by 1 bit (1 bit is Figure 3 The width of one symbol in the signal B) is obtained as Figure 3 The fixed bit width window b (dashed box) shown in the figure is used, and the center frequency and frequency deviation of the original uplink signal after filtering in the current fixed bit width window are calculated again to determine whether the center frequency and frequency deviation at this time meet the standards, and so on, until all the tests of the original uplink signal after filtering are completed.
[0090] Specifically, the average frequency can be the average frequency of the filtered original uplink signal within 1 bit time. In a window with a fixed bit width, the average frequency of each bit time is calculated, that is, the average frequency of a section of the filtered original uplink signal corresponding to a 0 or a 1 is calculated to obtain multiple average frequencies. From the multiple average frequencies in the window with a fixed bit width, the maximum average frequency and minimum average frequency corresponding to 0, the maximum average frequency and minimum average frequency corresponding to 1 are obtained, and the maximum average frequency corresponding to 0, the minimum average frequency corresponding to 0, the maximum frequency corresponding to 1, and the minimum average frequency corresponding to 1 are used to calculate the center frequency and frequency deviation in the current fixed bit width window.
[0091] In another transponder testing method provided in an embodiment of the present application, the above step 7 may include steps 8 and 9:
[0092] Step 8: Through the formula:
[0093] f1=(f H +f L ) / 2 calculates the center frequency of the original uplink signal after filtering, where f1 is the center frequency, f H is the average probability of the lower sideband, f L is the average probability of the lower sideband;
[0094] Step 9: Through the formula:
[0095] f2=(f H -f L ) / 2 to calculate the frequency deviation of the original uplink signal after filtering, where f2 is the frequency deviation.
[0096] Among them, in the window of fixed bit width, the maximum average frequency f corresponding to 0 is obtained Lmax , the minimum average frequency f corresponding to 0 Lmin , the maximum frequency f corresponding to 1 Hmax The minimum average frequency f corresponding to 1 Hmin . Use the formula: f 11 =(f Hmax +f Lmax ) / 2 and formula: f 12 =(f Hmin +f Lmin ) / 2 calculates the center frequency of the original uplink signal after filtering within a window of fixed bit width; using the formula: f 21 =(f Hmin -f Lmax ) / 2 and formula: f 22 =(f Hmin -f Lmax ) / 2 calculates the frequency deviation of the original uplink signal after filtering in a window with a fixed bit width, where f11 and f 12 is the center frequency, f 21 and f 22 is the frequency deviation.
[0097] Furthermore, by f1=(f H +f L ) / 2=4.234MHz±175kHz to evaluate the center frequency of the original uplink signal after filtering in a window with a fixed bit width; through f2=(f H -f L ) / 2=282.24×(1±7%)kHz to evaluate the frequency deviation of the original uplink signal after filtering within a window of fixed bit width. Specifically, when the following conditions are met:
[0098] (f Hmax +f Lmax ) / 2<4.234MHz+175kHz=4.409MHz;
[0099] (f Hmax +f Lmax ) / 2>4.234MHz-175kHz=4.059MHz;
[0100] (f Hmax -f Lmin ) / 2<282.24×(1+7%)kHz=302.00kHz;
[0101] (f Hmin -f Lmax ) / 2>282.24×(1-7%)kHz=262.48kHz;
[0102] It can be determined that the center frequency and frequency deviation of the filtered original uplink signal within the fixed bit width window meet the standards.
[0103] According to another transponder testing method provided in an embodiment of the present application, before step 4 above, steps 10 to 12 may be further included:
[0104] Step 10: Obtaining the instantaneous power of the sinusoidal signal and determining the difference between the instantaneous power and a preset power;
[0105] If the absolute value of the difference is greater than the preset threshold, step 11 is executed; if the absolute value of the difference between the instantaneous power and the preset power is less than the preset threshold, step 12 is executed;
[0106] Step 11: adjusting the amplitude of the sinusoidal signal until the absolute value of the difference between the instantaneous power and the preset power is less than a preset threshold;
[0107] Step 12: Confirm that the transponder test is completed.
[0108] Among them, since the hardware environment conditions will age to a certain extent over time, this aging is difficult to directly quantify. Therefore, in the power convergence process of the sinusoidal signal, this embodiment adopts an adaptive learning convergence algorithm. The algorithm can record recent convergence records (number of adjustments and instantaneous power after each adjustment), and automatically adjust the convergence algorithm parameters by judging the performance changes of the hardware and recent convergence records to improve the test efficiency. This embodiment can record the first number of adjustments and the instantaneous power after each adjustment. The first number of adjustments is the number of times the amplitude of the sinusoidal signal is adjusted during the current transponder test. When the next transponder test begins, if the difference between the second number of adjustments in the next transponder test and the first number of adjustments is not less than a preset multiple of the first number of adjustments, the preset threshold is adjusted according to the recorded instantaneous power. The second number of adjustments is the number of times the amplitude of the sinusoidal signal is adjusted in the next transponder test. The preset multiple can be 0.5 times. Specifically, in this embodiment, during the current transponder test, the number of adjustments and the instantaneous power after each adjustment can be recorded. This record can be used to optimize the adaptive learning convergence algorithm, making the power convergence in the next transponder test more accurate. For example, in the current transponder test, the adaptive learning convergence algorithm adjusted the amplitude of the sinusoidal signal four times before the absolute value of the difference between the instantaneous power and the preset power was less than a preset threshold. The adjustment values of the instantaneous power for each adjustment were 20, 36, 45, and 52. The four adjustment times and the four adjustment values (20, 36, 45, and 52) are recorded, and the adaptive learning convergence algorithm performs algorithm optimization based on the record. In the next transponder test, the optimized adaptive learning convergence algorithm adjusted the amplitude of the sinusoidal signal six times before the absolute value of the difference between the instantaneous power and the preset power was less than the preset threshold. After the adaptive learning convergence algorithm is optimized, if the number of adjustments for the next transponder test is 50% more than the number of adjustments for the current transponder test, it means that the hardware environment conditions of the system have aged and the original preset threshold is difficult to reach. In this case, the preset threshold needs to be changed to adapt to the current system status. This embodiment can effectively reduce the impact of hardware aging on the transponder test results through the self-optimization of the adaptive learning convergence algorithm. The preset threshold in this embodiment is (-0.1dBm, +0.1dBm), that is, when the difference between the instantaneous power and the preset power is within the value range of the preset threshold, the amplitude of the sinusoidal signal will no longer be adjusted, and the signal with the current amplitude will be used to edit the vehicle excitation signal.
[0109] Corresponding to a transponder testing method provided in an embodiment of the present application, an embodiment of the present application also provides a transponder testing device.
[0110] like Figure 4 As shown, an embodiment of the present application further provides a transponder testing device, which may include:
[0111] The excitation signal acquisition unit 100 is used to generate a vehicle passing excitation signal and send the vehicle passing excitation signal to the transponder to be tested;
[0112] The original uplink signal acquisition unit 110 is used to acquire the original uplink signal output by the balise under test after receiving the vehicle excitation signal;
[0113] The uplink signal acquisition unit 120 is configured to filter and perform demodulation preprocessing on the original uplink signal to obtain an uplink signal;
[0114] The signal demodulation unit 130 is used to demodulate the uplink signal to obtain a demodulated signal;
[0115] The noise processing unit 140 is used to process the noise in the demodulated signal;
[0116] A data calculation unit 150 is configured to calculate a center frequency and a frequency offset of the filtered original uplink signal based on the filtered original uplink signal and the processed demodulated signal;
[0117] If the center frequency is within the first preset range and the frequency deviation is within the second preset range, the result output unit 160 is triggered;
[0118] The result output unit 160 is used to determine whether the transponder under test has passed the test.
[0119] In another transponder testing device provided according to an embodiment of the present application, the uplink signal acquisition unit 120 may be configured to filter the original uplink signal as follows:
[0120] A bandpass filter is used to filter out the vehicle passing excitation signal in the original uplink signal.
[0121] In another transponder testing device provided according to an embodiment of the present application, the uplink signal acquisition unit 120 performs demodulation preprocessing to obtain an uplink signal, which can be specifically configured as follows:
[0122] The filtered original uplink signal is subjected to phase transformation to obtain an uplink signal, and the uplink signal differs from the filtered original uplink signal by a preset phase.
[0123] In another transponder testing device provided according to an embodiment of the present application, the noise processing unit 140 may include:
[0124] Get the standard bit rate of the transponder uplink signal;
[0125] The demodulated signal is noise filtered using a standard bit rate.
[0126] In another transponder testing device provided according to an embodiment of the present application, generating a passing vehicle excitation signal in the excitation signal acquiring unit 100 may specifically include:
[0127] Get a continuous sinusoidal signal with a fixed amplitude;
[0128] The continuous sinusoidal signal is amplitude edited to obtain a passing vehicle excitation signal. The passing vehicle excitation signal is a signal with three stages. The first stage is the amplitude enhancement stage, the second stage is the amplitude balance stage, and the third stage is the amplitude reduction stage.
[0129] In another transponder testing device provided according to an embodiment of the present application, the data calculation unit 150 may include:
[0130] a signal interval determination subunit, configured to determine multiple intervals of the filtered original uplink signal based on the processed demodulated signal, wherein one interval corresponds to a 0 or a 1 in the processed demodulated signal, an interval corresponding to a 1 is an upper sideband of the filtered original uplink signal, and an interval corresponding to a 0 is a lower sideband of the filtered original uplink signal;
[0131] a frequency acquisition subunit, configured to select a partial interval of the filtered original uplink signal and obtain an average frequency of an upper sideband and an average frequency of a lower sideband in the partial interval, wherein a total width of the partial interval satisfies a preset bit width;
[0132] The parameter calculation subunit is used to calculate the center frequency and frequency deviation of the filtered original uplink signal according to the average frequency of the upper sideband and the average frequency of the lower sideband.
[0133] In another transponder testing device provided according to an embodiment of the present application, the parameter calculation subunit may include:
[0134] The center frequency calculation subunit is used to calculate the frequency by the formula:
[0135] f1=(f H +f L ) / 2 calculates the center frequency of the original uplink signal after filtering, where f1 is the center frequency, f H is the average probability of the lower sideband, f L is the average probability of the lower sideband;
[0136] The frequency deviation calculation subunit is used to calculate the frequency deviation through the formula:
[0137] f2=(f H -f L ) / 2 to calculate the frequency deviation of the original uplink signal after filtering, where f2 is the frequency deviation.
[0138] In another transponder testing device provided in an embodiment of the present application, before amplitude editing of the continuous sinusoidal signal is performed in the excitation signal acquisition unit 100 to obtain the passing vehicle excitation signal, the device may further include:
[0139] A difference acquisition unit, configured to acquire the instantaneous power of the sinusoidal signal and determine the difference between the instantaneous power and a preset power;
[0140] If the absolute value of the difference is greater than a preset threshold, the amplitude adjustment unit is triggered;
[0141] The amplitude adjustment unit is used to adjust the amplitude of the sinusoidal signal until the absolute value of the difference between the instantaneous power and the preset power is smaller than a preset threshold.
[0142] According to another transponder testing device provided in an embodiment of the present application, the device may further include:
[0143] a power recording unit, configured to record a first adjustment number and the instantaneous power after each adjustment, wherein the first adjustment number is the number of times the amplitude of the sinusoidal signal is adjusted during the current transponder test;
[0144] When the next transponder test starts, if the difference between the second adjustment number and the first adjustment number in the next transponder test is not less than a preset multiple of the first adjustment number, triggering the threshold adjustment unit;
[0145] The trigger threshold adjustment unit is used to adjust the preset threshold according to the recorded instantaneous power, and the second adjustment number is the number of times the amplitude of the sinusoidal signal is adjusted in the next transponder test.
[0146] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the steps in the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.
[0147] In a typical configuration, the device includes one or more processors (CPUs), memory, and a bus. The device may also include input / output interfaces, network interfaces, and the like.
[0148] Memory may include non-permanent memory in a computer-readable storage medium, random access memory (RAM), and / or non-volatile memory, such as read-only memory (ROM) or flash RAM. Memory includes at least one memory chip. Memory is an example of a computer-readable medium.
[0149] Computer-readable storage media include permanent and non-permanent, removable and non-removable media that can be implemented by any method or technology to store information. The information can be computer-readable instructions, data structures, program modules, or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disc read-only memory (CD-ROM), digital versatile disc (DVD) or other optical storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other non-transmission media that can be used to store information that can be accessed by a computing device. As defined herein, computer-readable media does not include transitory computer-readable media (transitory media), such as modulated data signals and carrier waves.
[0150] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Furthermore, the present application may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.
[0151] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. It should also be noted that the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, commodity, or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, commodity, or device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, commodity, or device comprising the element.
[0152] Each embodiment in this specification is described in a related manner. Similar portions between the embodiments can be referred to in conjunction with each other. Each embodiment focuses on the differences from other embodiments. In particular, the device embodiments are generally similar to the method embodiments, so their description is relatively simple. For related portions, refer to the description of the method embodiments.
[0153] The above are merely embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application should all be included within the scope of the claims of the present application.
Claims
1. A transponder testing method, characterized in that: The method comprises: Generate a vehicle passing excitation signal and send the vehicle passing excitation signal to the transponder to be tested; Collecting the original uplink signal output by the transponder to be tested after receiving the vehicle passing excitation signal; Filtering and demodulating the original uplink signal to obtain an uplink signal; Demodulating the uplink signal to obtain a demodulated signal; Processing the noise in the demodulated signal; Calculate the center frequency and frequency deviation of the filtered original uplink signal through the filtered original uplink signal and the processed demodulated signal; If the center frequency is within the first preset range and the frequency deviation is within the second preset range, it is determined that the transponder to be tested passes the test.
2. The method according to claim 1, characterized in that The filtering of the original uplink signal comprises: A bandpass filter is used to filter out the vehicle passing excitation signal in the original uplink signal.
3. The method according to claim 1, characterized in that The demodulation preprocessing to obtain an uplink signal includes: The uplink signal is obtained by performing a phase transformation on the filtered original uplink signal, and the uplink signal differs from the filtered original uplink signal by a preset phase.
4. The method according to claim 1, characterized in that: The processing of the noise in the demodulated signal comprises: Obtain the standard code rate of the transponder uplink signal; The demodulated signal is subjected to noise filtering using the standard code rate.
5. The method according to claim 1, characterized in that The generating of the vehicle passing excitation signal comprises: Get a continuous sinusoidal signal with fixed amplitude; The continuous sinusoidal signal is amplitude edited to obtain the vehicle passing excitation signal, which is a signal with three stages, the first stage is the amplitude enhancement stage, the second stage is the amplitude balance stage, and the third stage is the amplitude reduction stage.
6. The method according to claim 1, characterized in that The calculating the center frequency and the frequency deviation of the filtered original uplink signal by using the filtered original uplink signal and the processed demodulated signal comprises: Determine a plurality of intervals of the filtered original uplink signal according to the processed demodulated signal, wherein one interval corresponds to a 0 or a 1 in the processed demodulated signal, the interval corresponding to a 1 is an upper side frequency of the filtered original uplink signal, and the interval corresponding to a 0 is a lower side frequency of the filtered original uplink signal; Selecting a partial interval of the original uplink signal after filtering and obtaining an average frequency of an upper sideband and an average frequency of a lower sideband in the partial interval, wherein a total width of the partial interval satisfies a preset bit width; The center frequency and frequency deviation of the original uplink signal after filtering are calculated by the average frequency of the upper sideband and the average frequency of the lower sideband.
7. The method according to claim 6, characterized in that The calculating the center frequency and the frequency deviation of the filtered original uplink signal by using the average frequency of the upper sideband and the average frequency of the lower sideband includes: By formula: f1=(f H +f L ) / 2 calculate the center frequency of the original uplink signal after filtering, where f1 is the center frequency, f H is the average probability of the lower sideband, f L is the average probability of the lower sideband; By formula: f2=(f H -f L ) / 2 calculates the frequency deviation of the original uplink signal after filtering, where f2 is the frequency deviation.
8. The method according to claim 5, characterized in that Before the amplitude of the continuous sinusoidal signal is edited to obtain the vehicle passing excitation signal, the method further includes: Obtaining the instantaneous power of the sinusoidal signal and determining the difference between the instantaneous power and a preset power; If the absolute value of the difference is greater than a preset threshold, adjusting the amplitude of the sinusoidal signal until the absolute value of the difference between the instantaneous power and the preset power is less than a preset threshold; If the absolute value of the difference between the instantaneous power and the preset power is smaller than the preset threshold, it is confirmed that the transponder test is finished.
9. The method according to claim 8, characterized in that Also includes: Recording the first adjustment number and the instantaneous power after each adjustment, wherein the first adjustment number is the number of times the amplitude of the sinusoidal signal is adjusted during the current transponder test; When the next transponder test starts, if the difference between the second adjustment number in the next transponder test and the first adjustment number is not less than a preset multiple of the first adjustment number, the preset threshold is adjusted according to the recorded instantaneous power, and the second adjustment number is the number of times the amplitude of the sinusoidal signal is adjusted in the next transponder test.
10. A transponder testing device, characterized in that: The device comprises: An excitation signal acquisition unit, used for generating a vehicle passing excitation signal and sending the vehicle passing excitation signal to the transponder to be tested; An original uplink signal acquisition unit, used for acquiring the original uplink signal output by the transponder to be tested after receiving the vehicle passing excitation signal; An uplink signal acquisition unit, configured to filter and perform demodulation preprocessing on the original uplink signal to obtain an uplink signal; A signal demodulation unit, used to demodulate the uplink signal to obtain a demodulated signal; A noise processing unit, used for processing the noise in the demodulated signal; A data calculation unit, configured to calculate a center frequency and a frequency deviation of the filtered original uplink signal through the filtered original uplink signal and the processed demodulated signal; If the center frequency is within a first preset range and the frequency deviation is within a second preset range, triggering a result output unit; The result output unit is used to determine whether the transponder to be tested passes the test.