Gsm-r network operation quality evaluation method and device

Abstract

The application discloses a GSM-R network operation quality evaluation method and device, wherein the method comprises the following steps: acquiring GSM-R cell in-line quadrature I / Q signals along a railway; identifying the arrival time of a frequency correction channel FCCH signal in the I / Q signals according to the timing characteristics of GSM-R complex frames; obtaining the measured phase sequence of the FCCH signal by intercepting the signal segment according to the arrival time of the FCCH signal; calculating the instantaneous phase difference between each sampling point in the measured phase sequence of the FCCH signal and an FCCH ideal phase model to obtain an instantaneous phase difference sequence; the FCCH ideal phase model is constructed according to FCCH standard parameters; and obtaining the GSM-R network operation quality evaluation result according to the statistical characteristics of the instantaneous phase difference sequence. The application can improve the accuracy of the GSM-R network quality evaluation result, simplify the evaluation logic and does not depend on the terminal performance.

Description

Technical Field

[0001] This invention relates to the field of rail communication technology, and more particularly to a method and apparatus for evaluating the quality of GSM-R network operations. Background Technology

[0002] Existing GSM-R (Global System for Mobile Communications - Railway) network quality evaluation technologies have many insurmountable shortcomings, specifically as follows: (1) The evaluation results are not consistent with the quality of wireless network use and are difficult to scientifically reflect the changes in equipment status and wireless environment; (2) High redundancy in evaluation logic: Some technologies introduce multiple indirect indicators such as received level, carrier-to-interference ratio, and bit error rate, which require complex weighted calculations. This not only increases the complexity of evaluation, but also these indicators are all indirect representations of channel impairments, and cannot evaluate network quality from a physical perspective.

[0003] (3) Evaluation indicators depend on terminal performance: Existing technologies mostly use service layer indicators such as wireless connection rate, call drop rate, handover success rate, and RxQual (Received Signal Quality). These indicators are secondary results after the terminal demodulates and decodes the air interface signal. They are greatly affected by the terminal demodulation algorithm, radio frequency sensitivity, and baseband processing capability. The results measured by different terminals in the same network are significantly different, which cannot objectively reflect the signal transmission quality of the wireless network itself. It is easy to misjudge terminal performance and faults as network problems. Summary of the Invention

[0004] This invention provides a method for evaluating the operational quality of GSM-R networks, overcoming the problems of low accuracy, redundant evaluation logic, and reliance on terminal performance in existing GSM-R network quality evaluation methods. The method includes: Acquire in-phase orthogonal I / Q signals from GSM-R cells along the railway line; Based on the timing characteristics of GSM-R multiframes, identify the arrival time of the frequency correction channel (FCCH) signal in the GSM-R cell I / Q signals; Based on the arrival time of the FCCH signal, a signal segment is extracted from the GSM-R cell I / Q signal to obtain the measured phase sequence of the FCCH signal; The instantaneous phase difference between each sampling point in the measured phase sequence of the FCCH signal and the ideal phase model of the FCCH is calculated to obtain an instantaneous phase difference sequence characterizing the degree of FCCH phase distortion; the ideal phase model of the FCCH is constructed based on the FCCH standard parameters of GSM-R. Based on the statistical characteristics of the instantaneous phase difference sequence, the evaluation results of the GSM-R network utilization quality are obtained.

[0005] This invention also provides a GSM-R network utilization quality assessment device to overcome the problems of low accuracy of evaluation results, redundant evaluation logic, and dependence on terminal performance in existing GSM-R network quality assessment methods. The device includes: The GSM-R signal acquisition module is used to acquire in-phase orthogonal I / Q signals from GSM-R cells along the railway line. The FCCH signal location module is used to: identify the arrival time of the frequency correction channel (FCCH) signal in the GSM-R cell I / Q signal based on the timing characteristics of the GSM-R multiframe; The FCCH phase acquisition module is used to: extract signal segments from the GSM-R cell I / Q signals based on the arrival time of the FCCH signal, and obtain the measured phase sequence of the FCCH signal; The FCCH phase distortion analysis module is used to: calculate the instantaneous phase difference between each sampling point in the measured phase sequence of the FCCH signal and the ideal phase model of the FCCH, and obtain an instantaneous phase difference sequence characterizing the degree of FCCH phase distortion; the ideal phase model of the FCCH is constructed according to the FCCH standard parameters of GSM-R; The network usage quality assessment module is used to obtain the GSM-R network usage quality assessment result based on the statistical characteristics of the instantaneous phase difference sequence.

[0006] This invention also provides a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the above-described GSM-R network utilization quality assessment method.

[0007] This invention also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the above-described GSM-R network utilization quality assessment method.

[0008] This invention also provides a computer program product, which includes a computer program that, when executed by a processor, implements the above-described GSM-R network application quality assessment method.

[0009] Compared with existing technologies that suffer from low accuracy, redundant evaluation logic, and reliance on terminal performance, this invention acquires the in-phase (in-phase) and quadrature (I / Q) signals of a GSM-R cell, identifies the arrival time of the FCCH signal based on the timing characteristics of GSM-R multiframes, and extracts signal segments to obtain the measured phase sequence of the FCCH. It calculates the instantaneous phase difference between the measured phase and the ideal phase model of the FCCH, and obtains the GSM-R network quality assessment result based on the statistical characteristics of the instantaneous phase difference sequence. This allows for direct evaluation of GSM-R network quality using the phase distortion degree of the physical layer FCCH signal, thus completely eliminating the influence of terminal performance on the evaluation results. It solves the technical problem in existing technologies where evaluation results depend on terminal performance and cannot objectively reflect the signal transmission quality of the wireless network itself. Simultaneously, it avoids redundant weighted calculations of multiple indicators, achieving a simple and accurate network quality evaluation with a single physical layer fundamental indicator. Attached Figure Description

[0010] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. In the drawings: Figure 1 This is a flowchart illustrating the quality assessment method used in the GSM-R network in an embodiment of the present invention. Figure 2 This is a physical structure diagram of a device for implementing a quality assessment method for GSM-R networks in an embodiment of the present invention; Figure 3 This is another flowchart illustrating the quality assessment method used in GSM-R networks in this embodiment of the invention; Figure 4 This is a schematic diagram of the GSM-R network quality assessment device in an embodiment of the present invention; Figure 5 This is another schematic diagram of the GSM-R network quality assessment device in an embodiment of the present invention; Figure 6 This is another schematic diagram of the GSM-R network application quality assessment device in an embodiment of the present invention. Detailed Implementation

[0011] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings. Here, the illustrative embodiments of the present invention and their descriptions are used to explain the present invention, but are not intended to limit the present invention.

[0012] The GSM-R communication network employs GMSK constant envelope phase modulation technology. The transmission quality of its air interface signal (the air interface, or air interface, is the wireless interface between terminal equipment and network equipment in a wireless communication system) is the core factor determining the network's operational status. Existing technologies using various indicators to evaluate wireless network quality are all indirect indicators obtained from the original signal, relying on terminal processing such as demodulation and decoding, and cannot objectively reflect the signal transmission quality of the wireless network itself.

[0013] The inventors discovered that the phase characteristics of FCCH (Frequency Correction Channel) are not affected by the terminal decoding algorithm or hardware performance, but are determined only by the network-side wireless channel and equipment hardware defects (multipath fading, interference, frequency offset, clock error, and RF hardware nonlinearity), making it the best carrier for characterizing the operating quality of wireless networks.

[0014] To overcome the shortcomings of existing GSM-R network quality evaluation technologies, this invention proposes a GSM-R network application quality assessment method. Utilizing the inherent characteristics of the FCCH signal, the physical layer FCCH signal is directly captured from the air interface using an RF acquisition instrument, bypassing terminal receiver processing. The phase distortion of the FCCH signal is used as a direct quantification of signal integrity impairment, directly measuring wireless network quality and thus completely eliminating the influence of terminal performance on the evaluation results.

[0015] Figure 1 This is a flowchart illustrating the quality assessment method used in the GSM-R network in an embodiment of the present invention. Figure 1 As shown, this method can be implemented in the following steps: Step 101: Obtain in-phase orthogonal I / Q signals from GSM-R cells along the railway line; Step 102: Based on the timing characteristics of GSM-R multiframes, identify the arrival time of the frequency correction channel (FCCH) signal in the GSM-R cell I / Q signals; Step 103: Using the arrival time of the FCCH signal as a reference, extract signal segments from the GSM-R cell I / Q signals to obtain the measured phase sequence of the FCCH signal; Step 104: Calculate the instantaneous phase difference between each sampling point in the measured phase sequence of the FCCH signal and the ideal phase model of the FCCH, to obtain an instantaneous phase difference sequence characterizing the degree of FCCH phase distortion; the ideal phase model of the FCCH is constructed based on the FCCH standard parameters of GSM-R. Step 105: Based on the statistical characteristics of the instantaneous phase difference sequence, obtain the GSM-R network utilization quality assessment results.

[0016] Compared with existing technologies that suffer from low accuracy, redundant evaluation logic, and reliance on terminal performance, this invention acquires GSM-R cell I / Q signals, identifies the arrival time of the FCCH signal based on the timing characteristics of GSM-R multiframes, and extracts signal segments to obtain the measured phase sequence of the FCCH. It calculates the instantaneous phase difference between the measured phase and the ideal phase model of the FCCH, and obtains the GSM-R network utilization quality assessment result based on the statistical characteristics of the instantaneous phase difference sequence. This allows for direct evaluation of GSM-R network quality using the phase distortion degree of the physical layer FCCH signal, thus completely eliminating the influence of terminal performance on the evaluation results. It solves the technical problem in existing technologies where evaluation results depend on terminal performance and cannot objectively reflect the signal transmission quality of the wireless network itself. Simultaneously, it avoids redundant weighted calculations of multiple indicators, achieving a simple and accurate network quality evaluation with a single physical layer fundamental indicator.

[0017] Figure 2 This is a physical structure diagram of a device for implementing a quality assessment method for GSM-R networks in an embodiment of the present invention. Figure 2 As shown, the physical structure of the device mainly includes: a display unit, a control and calculation unit, a data acquisition unit, and a system power supply. The display unit serves as a human-machine interface, the system power supply serves as an AC220V power input interface, and the data acquisition unit serves as an air interface for receiving radio signals.

[0018] Figure 2 The control and operation unit specifically includes a real-time processing unit and a system controller. The real-time processing unit performs channelization processing, cell signal extraction, FCCH dynamic tracking, phase difference calculation, and quality index construction on broadband I / Q data. The system controller receives the evaluation results from the real-time processing unit, processes them in conjunction with mileage information, and drives the display unit. The display unit uses a system display to show the real-time GSM-R network operation quality evaluation results, network quality level, and quality distribution map along the route.

[0019] In another example, the real-time processing unit is implemented using a high-performance digital signal processor (DSP) or field-programmable gate array (FPGA) to execute multiphase filtering channelization algorithms, matched filtering detection algorithms, FCCH phase extraction algorithms, and GQI calculations. The system controller uses an embedded processor or industrial control computer to coordinate the timing of the acquisition unit and the real-time processing unit, receive mileage information (e.g., from GPS or wheel axle sensors), correlate the evaluation results with the mileage, and drive the display unit for visualization.

[0020] To obtain raw data for network quality assessment, it is first necessary to collect and extract the I / Q signals of GSM-R cells from the wireless signals along the railway line.

[0021] In this embodiment of the invention, GSM-R cell I / Q signals along the railway line are acquired.

[0022] For example, during the testing of a dynamic inspection train, a high-precision radio frequency acquisition instrument is used to acquire the GSM-R band wireless signal under test. The sampling frequency is set to 200kHz and the sampling bit depth to 16bit, obtaining the digital baseband I / Q signal, denoted as... ,in For in-phase branch signals, For orthogonal branch signals, The sampling point number, It is the imaginary unit.

[0023] Furthermore, channelization processing can be used to separate the various GSM-R channel signals from the broadband signal.

[0024] In one embodiment, a multiphase filtering algorithm is used to channelize the broadband I / Q signals along the railway line; based on the configuration information of the GSM-R cell operating parameters and the mileage information of the railway line, the GSM-R cell I / Q signals are extracted from the channelized I / Q signals.

[0025] For example, a multiphase filtering algorithm is used to channelize broadband I / Q signals, combined with an adaptive extraction of GSM-R cell signals from a ledger, and effective data is extracted based on mileage information. The ledger contains the operating parameter configuration information of each cell along the GSM-R route, used to identify and match target cell signals.

[0026] To eliminate interference and noise introduced during signal acquisition, the extracted I / Q signals need to be preprocessed. In one embodiment, the GSM-R cell I / Q signals are preprocessed, including mean subtraction, low-pass filtering, and amplitude normalization.

[0027] For example, in preprocessing the I / Q signals of a GSM-R cell, the DC offset is first eliminated using the mean subtraction method, calculated as follows: , ,in: After mean subtraction , for The mean; Q after mean subtraction , for The mean value is then used. High-frequency noise is filtered out using an FIR (Finite Impulse Response) low-pass filter (cutoff frequency 100kHz). Finally, the signal amplitude is normalized to the [-1, 1] interval to obtain the pre-processed, clean GSM-R cell I / Q signal.

[0028] In this embodiment of the invention, the arrival time of the frequency correction channel (FCCH) signal in the GSM-R cell I / Q signal is identified based on the timing characteristics of the GSM-R multiframe.

[0029] It should be noted that the FCCH signal, as the downlink synchronization reference channel of GSM-R, has the characteristics of a pure single frequency without data modulation. This characteristic can be used to accurately locate the position of the FCCH signal. For example, a GSM-R multiframe consists of 51 TDMA frames with a duration of 235.36ms. The FCCH channel has a fixed timing position in the multiframe, appearing once every 10 TDMA frames.

[0030] Therefore, by utilizing the frequency characteristics of the FCCH single-frequency signal, the position of the FCCH can be accurately detected through matched filtering.

[0031] In one embodiment, the timing characteristics of the GSM-R multiframe include: the timing position characteristics of the FCCH channel in the GSM-R multiframe; and, based on the timing position characteristics of the FCCH channel in the GSM-R multiframe, performing matched filtering on the GSM-R cell I / Q signals to identify the arrival time of the FCCH signal in the GSM-R cell I / Q signals.

[0032] For example, for the preprocessed I / Q signal, the FCCH single-tone (67.7kHz) matched filtering method is used to detect the first 3 to 5 consecutive clear FCCH signals and construct a signal template for matching the FCCH. By performing sliding convolution on the I / Q signals and a signal template, a peak appears in the convolution result when the signal template is aligned with the FCCH in the I / Q signals. The arrival time of the FCCH signal is precisely determined based on the peak position. , ... ,in Representing the One FCCH signal.

[0033] The multiframe period can be estimated by identifying a small number of consecutive FCCH signals, thereby determining the theoretical arrival time of subsequent FCCH signals without having to perform matched filtering detection on each subsequent FCCH.

[0034] In one embodiment, based on the timing position characteristics of the FCCH channel in the GSM-R multiframe, matched filtering is performed on the GSM-R cell I / Q signals to identify the actual arrival times of multiple consecutive FCCH signals in the GSM-R cell I / Q signals; based on the actual arrival times of the multiple consecutive FCCH signals, the timing period of the GSM-R multiframe is calculated; based on the actual arrival time of the last identified FCCH signal and the timing period of the GSM-R multiframe, the theoretical arrival time of the subsequent FCCH signals is calculated; the actual arrival time of the last identified FCCH signal and the theoretical arrival time of the subsequent FCCH signals are determined as the arrival times of the FCCH signals in the GSM-R cell I / Q signals.

[0035] In one embodiment, the theoretical arrival time of subsequent FCCH signals is calculated based on the actual arrival time of the last identified FCCH signal, the timing period of the GSM-R multiframe, and the timing fine-tuning amount; the timing fine-tuning amount is used to compensate for signal propagation delay deviation in high-speed mobile scenarios.

[0036] For example, based on the arrival time of the FCCH signal identified through matched filtering, the 51-frame timing reference of GSM-R is calibrated, and the fixed period of the FCCH is determined to be... =235.36ms (51 TDMA frames constitute a multiframe, with a duration of 235.36ms). Based on the fixed period of FCCH, the theoretical arrival time of the FCCH signal is calculated using the following formula: ,in For the first The theoretical arrival time of each FCCH signal For the first The actual arrival time of each FCCH This is a timing fine-tuning variable used to compensate for signal propagation delay deviations in high-speed mobile scenarios.

[0037] To achieve robust tracking of the FCCH in complex electromagnetic environments, an iterative tracking strategy combining advance calculation of the theoretical arrival time of the FCCH and window detection is required.

[0038] In one embodiment, based on the timing position characteristics of the FCCH channel in the GSM-R multiframe, matched filtering is performed on the GSM-R cell I / Q signals to identify the actual arrival times of multiple consecutive FCCH signals in the GSM-R cell I / Q signals; the timing period of the GSM-R multiframe is calculated based on the actual arrival times of the multiple consecutive FCCH signals; taking the actual arrival time of the last identified FCCH signal as the current time, the actual arrival times of subsequent FCCH signals are iteratively identified in the following manner, and the actual arrival times of the multiple consecutive FCCH signals and the actual arrival times of subsequent FCCH signals are determined as the arrival times of the FCCH signals in the GSM-R cell I / Q signals: the theoretical arrival time of the next FCCH signal is calculated based on the current time and the timing period of the GSM-R multiframe; a sliding detection window is set with the theoretical arrival time of the next FCCH signal as the center, and matched filtering is performed on the GSM-R cell I / Q signals within the sliding detection window to obtain the actual arrival time of the next FCCH signal; the actual arrival time of the next FCCH signal is updated to the current time.

[0039] For example, in A sliding detection window is set within a ±4-bit time range (corresponding to ±0.02ms), and the GSM-R cell I / Q signals within the window are subjected to FCCH single-tone matched filtering again. If the detection peak value of the matched filter is higher than the preset detection threshold... Then the actual arrival time of the current FCCH signal is directly locked. When the FCCH is disturbed and its features are not obvious, the detection peak value of the matched filter is lower than the detection threshold. At that time, the center position of the current FCCH signal is determined by calculating using the previously locked FCCH positions (arrival times of the FCCH signal). The calculation formula is as follows: ,in The estimated position of the currently disturbed FCCH. , These represent the actual arrival times of the locked FCCH signals, respectively. In another example, by repeatedly performing the above calculation and detection processes, the arrival times of the required number of FCCH signals can be obtained.

[0040] To further improve the accuracy of the theoretical arrival time estimation and ensure the stability of long-term tracking, the deviation between the actual arrival time and the theoretical arrival time obtained from each detection can be used to correct the model parameters.

[0041] In one embodiment, the theoretical arrival time of the next FCCH signal is calculated based on the current time, the timing period of the GSM-R multiframe, and the timing fine-tuning amount; the timing fine-tuning amount is used to compensate for signal propagation delay deviation in high-speed mobile scenarios; when iteratively identifying the actual arrival time of subsequent FCCH signals, the method further includes: whenever the actual arrival times of a preset number of FCCH signals are identified, calculating the deviation between the theoretical arrival time and the actual arrival time of each FCCH signal in the preset number of FCCH signals; and using the average deviation of the preset number of FCCH signals to correct the timing fine-tuning amount.

[0042] For example, for every preset number of FCCH signals tracked and located, the deviation between the actual arrival time and the theoretical arrival time is calculated. The average deviation between the actual arrival time and the theoretical arrival time of a preset number of FCCH signals is taken as the basis for timing fine-tuning. Make corrections to ensure the long-term stability of FCCH dynamic tracking.

[0043] After locking the arrival time of the FCCH, a high-quality signal segment needs to be extracted from the signal for phase analysis.

[0044] In this embodiment of the invention, the measured phase sequence of the FCCH signal is obtained by extracting a signal segment from the GSM-R cell I / Q signal based on the arrival time of the FCCH signal.

[0045] For example, for each tracked and locked FCCH signal (time slot), a stable signal segment of 20-30 bits in the middle is extracted to avoid transient interference at the beginning and end, thus obtaining a clean single-frequency FCCH signal. ,in , This is the pre-processed, clean GSM-R cell I / Q signal.

[0046] To ensure that the evaluation results accurately correspond to the mileage and facilitate data comparison across multiple trips and line maintenance guidance, it is necessary to perform equidistant resampling of the FCCH signal.

[0047] In one embodiment, continuous FCCH signals are selected from the GSM-R cell I / Q signals, and the selected FCCH signals are resampled at equal intervals according to a preset mileage interval; based on the arrival time of the resampled FCCH signals, signal segments are extracted from the resampled FCCH signals to obtain the measured phase sequence of the resampled FCCH signals.

[0048] For example, continuous FCCH signals from the I / Q signals of a GSM-R cell are selected to form an evaluation period; equidistant resampling is performed according to mileage to obtain the FCCH signals of all resampled points within the evaluation period.

[0049] To extract phase information from I / Q signals, the I / Q signals in Cartesian coordinates need to be converted into phase angles in polar coordinates.

[0050] In one embodiment, based on the arrival time of the FCCH signal, a signal segment is extracted from the GSM-R cell I / Q signal to obtain the FCCH single-frequency signal; the arctangent of each sampling point in the FCCH single-frequency signal is calculated in four quadrants to obtain the instantaneous phase sequence; the instantaneous phase sequence is de-wound to obtain the measured phase sequence of the FCCH signal.

[0051] For example, the instantaneous phase at each sampling point can be calculated using the four-quadrant arctangent function, and the calculation formula is as follows: ,in Sampling points The instantaneous phase at the point is measured, with a phase value range of [-180°, 180°], to ensure accurate quadrant determination of the signal.

[0052] The instantaneous phase sequence is obtained by unwinding. To eliminate phase jumps between 0° and 360°, the processing rule is: if ,but ;like ,but This yields a continuous and smooth measured phase sequence.

[0053] To quantify the phase distortion of the FCCH signal, it is necessary to compare the measured phase with the phase under ideal interference-free conditions.

[0054] In this embodiment of the invention, the instantaneous phase difference between each sampling point in the measured phase sequence of the FCCH signal and the ideal phase model of the FCCH is calculated to obtain an instantaneous phase difference sequence characterizing the degree of FCCH phase distortion; the ideal phase model of the FCCH is constructed according to the FCCH standard parameters of GSM-R.

[0055] For example, based on the FCCH standard parameters of GSM-R, an ideal FCCH linear phase model is constructed, and the calculation formula is as follows: ,in: The sampling point number, Sampling points under ideal, interference-free conditions The FCCH phase at that location.

[0056] The instantaneous phase difference at each sampling point is calculated using the following formula: ,in Sampling points The absolute difference between the measured phase and the ideal phase at a given point, expressed in units of 1. This characterizes the degree of FCCH phase distortion at a single sampling point.

[0057] After obtaining the instantaneous phase difference sequence, its statistical features need to be extracted to quantify the network operation quality.

[0058] In this embodiment of the invention, the GSM-R network utilization quality assessment result is obtained based on the statistical characteristics of the instantaneous phase difference sequence.

[0059] To obtain a more intuitive network quality score, statistical features need to be weighted and integrated into a single quality index.

[0060] In one embodiment, the statistical features include the mean and variance; the weighted fusion result of the mean and the variance is determined as the GSM-R network operation quality evaluation index value; and the level of GSM-R network operation quality is evaluated based on the relationship between the GSM-R network operation quality evaluation index value and a preset index threshold.

[0061] For example, consider the average phase difference and the variance of the phase difference among statistical sampling points: the formula for calculating the average phase difference is... The formula for calculating the phase difference variance is: ,in, For traversal parameters, For the first There are 1 phase difference, and N is the number of sampling points; Characterizing the overall phase deviation, Characterizes the degree of phase jitter.

[0062] For example, by weighting and fusing the average phase difference and the phase difference variance, a GSM-R network quality evaluation index (GQI) in the range of 0 to 100 is constructed. The calculation formula is as follows: ,in: For the average phase difference threshold, The phase difference variance threshold. , This is the weighting coefficient, which is typically set to 1.

[0063] A higher GQI value indicates better network quality. In one embodiment, network quality is graded based on GQI values, with the following grading criteria: For excellence For good, For general, For poor The range represents the extreme values, corresponding to different network operating states.

[0064] Figure 3 This is another flowchart illustrating the quality assessment method used in GSM-R networks in an embodiment of the present invention. Figure 3As shown, the dynamic testing vehicle continuously travels along the railway line, repeatedly performing the following steps: First, it receives radio signals, collects broadband I / Q data, and extracts GSM-R cell signals through channelization, completing the real-time extraction of GSM-R cell signals along the railway line; then, through signal preprocessing (DC removal and normalization), FCCH matched filtering to locate the FCCH, multiframe timing tracking, FCCH signal interception and phase extraction, instantaneous phase difference calculation, equidistant resampling and statistical analysis, GQI calculation, and operational quality grading, it achieves dynamic full-coverage detection of the GSM-R network operation quality along the railway line, providing accurate data support for railway GSM-R network operation and maintenance and network quality optimization.

[0065] The GSM-R network quality assessment method provided in this embodiment of the invention utilizes the fixed timing characteristics of GSM-R multiframes to achieve robust dynamic tracking of the FCCH channel. It evaluates the wireless network operation quality through measured FCCH phase, constructs a quality index, and realizes a logically simple, terminal performance-influenced, robust, and scientifically applicable objective evaluation method for network quality.

[0066] The GSM-R network quality assessment method provided in this embodiment of the invention has at least the following beneficial effects: (1) Objective evaluation without terminal interference: Only the pure phase characteristics of FCCH of GSM-R are used, without relying on the demodulation and decoding results of the terminal, without using any service layer KPI indicators, completely removing the influence of terminal performance on the evaluation results, and scientifically characterizing the operating quality of wireless network.

[0067] (2) The FCCH tracking is extremely robust and adaptable to high-speed and complex scenarios: Based on the fixed timing structure of GSM-R multiframes, the dynamic tracking method of "initial calibration + linear calculation + previous and next frame calculation" can stably lock the FCCH position even if the signal is blurred due to sudden interference or deep fading in a single frame, thus avoiding tracking loss of synchronization and adapting to various complex scenarios such as multipath interference and instantaneous electromagnetic interference.

[0068] (3) The evaluation logic is simple and the engineering implementation is strong: the redundant weighted calculation of multiple indicators is abandoned. The quality index is constructed by using only the mean and variance of the FCCH phase difference as the core input. The calculation process is simple and does not require complex algorithm support. It can be realized by relying on conventional high-precision radio frequency acquisition instruments without the need for additional hardware equipment, which facilitates engineering deployment and routine network monitoring.

[0069] (4) Accurate evaluation: As a pure carrier without data modulation, the phase distortion of FCCH directly reflects all channel damages (multipath, interference, frequency offset, clock error, hardware damage, etc.) in the network. Compared with traditional indirect indicators, the evaluation is more accurate and can more accurately reflect the network operating status. It can realize the fundamental and refined evaluation of network quality and provide accurate guidance for network optimization.

[0070] This invention also provides a GSM-R network usage quality assessment device, as described in the following embodiments. Since the principle by which this device solves the problem is similar to the GSM-R network usage quality assessment method, the implementation of this device can refer to the implementation of the GSM-R network usage quality assessment method; repeated details will not be elaborated further.

[0071] Figure 4 This is a schematic diagram of a GSM-R network quality assessment device in an embodiment of the present invention. Figure 4 As shown, the device includes: GSM-R signal acquisition module 401 is used to: acquire GSM-R cell in-phase quadrature I / Q signals along the railway line; The FCCH signal positioning module 402 is used to: identify the arrival time of the frequency correction channel FCCH signal in the GSM-R cell I / Q signal based on the timing characteristics of the GSM-R multiframe; The FCCH phase acquisition module 403 is used to: extract signal segments from the GSM-R cell I / Q signals based on the arrival time of the FCCH signal to obtain the measured phase sequence of the FCCH signal; The FCCH phase distortion analysis module 404 is used to: calculate the instantaneous phase difference between each sampling point in the measured phase sequence of the FCCH signal and the ideal phase model of the FCCH, and obtain an instantaneous phase difference sequence characterizing the degree of FCCH phase distortion; the ideal phase model of the FCCH is constructed according to the FCCH standard parameters of GSM-R; The network usage quality assessment module 405 is used to: obtain the GSM-R network usage quality assessment result based on the statistical characteristics of the instantaneous phase difference sequence.

[0072] In one embodiment, the GSM-R signal acquisition module 401 is specifically used for: The broadband I / Q signals along the railway line are channelized using a multiphase filtering algorithm. Based on the configuration information of the GSM-R cell operating parameters and the mileage information of the railway line, the GSM-R cell I / Q signal is extracted from the channelized I / Q signal.

[0073] Figure 5 This is another schematic diagram of the GSM-R network application quality assessment device in an embodiment of the present invention.

[0074] In one embodiment, such as Figure 5 As shown, Figure 4 The device also includes a signal preprocessing module 501, used for: The GSM-R cell I / Q signal is preprocessed, including mean subtraction, low-pass filtering, and amplitude normalization.

[0075] In one embodiment, the timing characteristics of the GSM-R multiframe include: the timing position characteristics of the FCCH channel in the GSM-R multiframe; FCCH signal positioning module 402 is specifically used for: Based on the timing position characteristics of the FCCH channel in the GSM-R multiframe, matched filtering is performed on the GSM-R cell I / Q signals to identify the arrival time of the FCCH signal in the GSM-R cell I / Q signals.

[0076] In one embodiment, the FCCH signal positioning module 402 is specifically used for: Based on the timing position characteristics of the FCCH channel in the GSM-R multiframe, matched filtering is performed on the GSM-R cell I / Q signals to identify the actual arrival times of multiple consecutive FCCH signals in the GSM-R cell I / Q signals. The timing period of the GSM-R multiframe is calculated based on the actual arrival times of the multiple consecutive FCCH signals. Based on the actual arrival time of the last identified FCCH signal and the timing period of the GSM-R multiframe, calculate the theoretical arrival time of subsequent FCCH signals; The actual arrival time of the last identified FCCH signal and the theoretical arrival time of the subsequent FCCH signals are determined as the arrival time of the FCCH signal in the GSM-R cell I / Q signal.

[0077] In one embodiment, the FCCH signal positioning module 402 is specifically used for: Based on the actual arrival time of the last identified FCCH signal, the timing period of the GSM-R multiframe, and the timing fine-tuning amount, the theoretical arrival time of subsequent FCCH signals is calculated; the timing fine-tuning amount is used to compensate for signal propagation delay deviation in high-speed mobile scenarios.

[0078] In one embodiment, the FCCH signal positioning module 402 is specifically used for: Based on the timing position characteristics of the FCCH channel in the GSM-R multiframe, matched filtering is performed on the GSM-R cell I / Q signals to identify the actual arrival times of multiple consecutive FCCH signals in the GSM-R cell I / Q signals. The timing period of the GSM-R multiframe is calculated based on the actual arrival times of the multiple consecutive FCCH signals. Using the actual arrival time of the last identified FCCH signal as the current time, the actual arrival times of subsequent FCCH signals are iteratively identified in the following manner. The actual arrival times of the multiple consecutive FCCH signals and the actual arrival times of subsequent FCCH signals are determined as the arrival times of the FCCH signals in the GSM-R cell I / Q signals: Calculate the theoretical arrival time of the next FCCH signal based on the current time and the timing period of the GSM-R multiframe; A sliding detection window is set with the theoretical arrival time of the next FCCH signal as the center, and matched filtering is performed on the GSM-R cell I / Q signals within the sliding detection window to obtain the actual arrival time of the next FCCH signal; Update the actual arrival time of the next FCCH signal to the current time.

[0079] Figure 6 This is another schematic diagram of the GSM-R network application quality assessment device in an embodiment of the present invention.

[0080] In one embodiment, the FCCH signal positioning module 402 is specifically used for: Based on the current time, the timing period of the GSM-R multiframe, and the timing fine-tuning amount, the theoretical arrival time of the next FCCH signal is calculated; the timing fine-tuning amount is used to compensate for the signal propagation delay deviation in high-speed mobile scenarios. like Figure 6 As shown, Figure 4 The device also includes an FCCH positioning calculation and correction module 601, used for: Whenever the actual arrival time of a preset number of FCCH signals is identified, the deviation between the theoretical arrival time and the actual arrival time of each FCCH signal in the preset number of FCCH signals is calculated; The timing fine-tuning amount is corrected using the average deviation of the preset number of FCCH signals.

[0081] In one embodiment, the FCCH phase acquisition module 403 is specifically used for: Select continuous FCCH signals from the GSM-R cell I / Q signals, and resample the selected FCCH signals at equal intervals according to the preset mileage interval; Based on the arrival time of the resampled FCCH signal, a signal segment is extracted from the resampled FCCH signal to obtain the measured phase sequence of the resampled FCCH signal.

[0082] In one embodiment, the FCCH phase acquisition module 403 is specifically used for: Based on the arrival time of the FCCH signal, a signal segment is extracted from the GSM-R cell I / Q signal to obtain the FCCH single-frequency signal; The instantaneous phase sequence is obtained by performing four-quadrant arctangent calculation on each sampling point in the FCCH single-frequency signal; The instantaneous phase sequence is unwound to obtain the measured phase sequence of the FCCH signal.

[0083] In one embodiment, the statistical characteristics include mean and variance; Network usage quality assessment module 405 is specifically used for: The weighted fusion result of the average value and the variance is determined as the GSM-R network operation quality evaluation index value; The level of GSM-R network operation quality is assessed based on the relationship between the GSM-R network operation quality evaluation index value and the preset index threshold.

[0084] This invention also provides a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the above-described GSM-R network utilization quality assessment method.

[0085] This invention also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the above-described GSM-R network utilization quality assessment method.

[0086] This invention also provides a computer program product, which includes a computer program that, when executed by a processor, implements the above-described GSM-R network application quality assessment method.

[0087] Compared with existing technologies that suffer from low accuracy, redundant evaluation logic, and reliance on terminal performance, this invention acquires GSM-R cell I / Q signals, identifies the arrival time of the FCCH signal based on the timing characteristics of GSM-R multiframes, and extracts signal segments to obtain the measured phase sequence of the FCCH. It calculates the instantaneous phase difference between the measured phase and the ideal phase model of the FCCH, and obtains the GSM-R network utilization quality assessment result based on the statistical characteristics of the instantaneous phase difference sequence. This allows for direct evaluation of GSM-R network quality using the phase distortion degree of the physical layer FCCH signal, thus completely eliminating the influence of terminal performance on the evaluation results. It solves the technical problem in existing technologies where evaluation results depend on terminal performance and cannot objectively reflect the signal transmission quality of the wireless network itself. Simultaneously, it avoids redundant weighted calculations of multiple indicators, achieving a simple and accurate network quality evaluation with a single physical layer fundamental indicator.

[0088] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0089] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0090] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0091] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0092] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for evaluating the quality of GSM-R network applications, characterized in that, include: Acquire in-phase orthogonal I / Q signals from GSM-R cells along the railway line; Based on the timing characteristics of GSM-R multiframes, identify the arrival time of the frequency correction channel (FCCH) signal in the GSM-R cell I / Q signals; Based on the arrival time of the FCCH signal, a signal segment is extracted from the GSM-R cell I / Q signal to obtain the measured phase sequence of the FCCH signal; The instantaneous phase difference between each sampling point in the measured phase sequence of the FCCH signal and the ideal phase model of the FCCH is calculated to obtain an instantaneous phase difference sequence characterizing the degree of FCCH phase distortion; the ideal phase model of the FCCH is constructed based on the FCCH standard parameters of GSM-R. Based on the statistical characteristics of the instantaneous phase difference sequence, the evaluation results of the GSM-R network utilization quality are obtained.

2. The method as described in claim 1, characterized in that, After acquiring the in-phase quadrature I / Q signals of GSM-R cells along the railway line, the process also includes: The GSM-R cell I / Q signal is preprocessed, including mean subtraction, low-pass filtering, and amplitude normalization.

3. The method as described in claim 1, characterized in that, The timing characteristics of the GSM-R multiframe include: the timing position characteristics of the FCCH channel in the GSM-R multiframe; Based on the timing characteristics of GSM-R multiframes, the arrival time of the FCCH signal in the GSM-R cell I / Q signals is identified, including: Based on the timing position characteristics of the FCCH channel in the GSM-R multiframe, matched filtering is performed on the GSM-R cell I / Q signals to identify the arrival time of the FCCH signal in the GSM-R cell I / Q signals.

4. The method as described in claim 3, characterized in that, Based on the timing position characteristics of the FCCH channel in the GSM-R multiframe, matched filtering is performed on the GSM-R cell I / Q signals to identify the arrival time of the FCCH signal in the GSM-R cell I / Q signals, including: Based on the timing position characteristics of the FCCH channel in the GSM-R multiframe, matched filtering is performed on the GSM-R cell I / Q signals to identify the actual arrival times of multiple consecutive FCCH signals in the GSM-R cell I / Q signals. The timing period of the GSM-R multiframe is calculated based on the actual arrival times of the multiple consecutive FCCH signals. Based on the actual arrival time of the last identified FCCH signal and the timing period of the GSM-R multiframe, calculate the theoretical arrival time of subsequent FCCH signals; The actual arrival time of the last identified FCCH signal and the theoretical arrival time of the subsequent FCCH signals are determined as the arrival time of the FCCH signal in the GSM-R cell I / Q signal.

5. The method as described in claim 4, characterized in that, Based on the actual arrival time of the last identified FCCH signal and the timing period of the GSM-R multiframe, the theoretical arrival times of subsequent FCCH signals are calculated, including: Based on the actual arrival time of the last identified FCCH signal, the timing period of the GSM-R multiframe, and the timing fine-tuning amount, the theoretical arrival time of subsequent FCCH signals is calculated; the timing fine-tuning amount is used to compensate for signal propagation delay deviation in high-speed mobile scenarios.

6. The method as described in claim 3, characterized in that, Based on the timing position characteristics of the FCCH channel in the GSM-R multiframe, matched filtering is performed on the GSM-R cell I / Q signals to identify the arrival time of the FCCH signal in the GSM-R cell I / Q signals, including: Based on the timing position characteristics of the FCCH channel in the GSM-R multiframe, matched filtering is performed on the GSM-R cell I / Q signals to identify the actual arrival times of multiple consecutive FCCH signals in the GSM-R cell I / Q signals. The timing period of the GSM-R multiframe is calculated based on the actual arrival times of the multiple consecutive FCCH signals. Using the actual arrival time of the last identified FCCH signal as the current time, the actual arrival times of subsequent FCCH signals are iteratively identified in the following manner. The actual arrival times of the multiple consecutive FCCH signals and the actual arrival times of subsequent FCCH signals are determined as the arrival times of the FCCH signals in the GSM-R cell I / Q signals: Calculate the theoretical arrival time of the next FCCH signal based on the current time and the timing period of the GSM-R multiframe; A sliding detection window is set with the theoretical arrival time of the next FCCH signal as the center, and matched filtering is performed on the GSM-R cell I / Q signals within the sliding detection window to obtain the actual arrival time of the next FCCH signal; Update the actual arrival time of the next FCCH signal to the current time.

7. The method as described in claim 6, characterized in that, Based on the current time and the timing period of the GSM-R multiframe, calculate the theoretical arrival time of the next FCCH signal, including: Based on the current time, the timing period of the GSM-R multiframe, and the timing fine-tuning amount, the theoretical arrival time of the next FCCH signal is calculated; the timing fine-tuning amount is used to compensate for the signal propagation delay deviation in high-speed mobile scenarios. The iterative identification of the actual arrival time of subsequent FCCH signals also includes: Whenever the actual arrival time of a preset number of FCCH signals is identified, the deviation between the theoretical arrival time and the actual arrival time of each FCCH signal in the preset number of FCCH signals is calculated; The timing fine-tuning amount is corrected using the average deviation of the preset number of FCCH signals.

8. The method as described in claim 1, characterized in that, Based on the arrival time of the FCCH signal, a signal segment is extracted from the GSM-R cell I / Q signal to obtain the measured phase sequence of the FCCH signal, including: Select continuous FCCH signals from the GSM-R cell I / Q signals, and resample the selected FCCH signals at equal intervals according to the preset mileage interval; Based on the arrival time of the resampled FCCH signal, a signal segment is extracted from the resampled FCCH signal to obtain the measured phase sequence of the resampled FCCH signal.

9. The method as described in claim 1, characterized in that, Based on the arrival time of the FCCH signal, a signal segment is extracted from the GSM-R cell I / Q signal to obtain the measured phase sequence of the FCCH signal, including: Based on the arrival time of the FCCH signal, a signal segment is extracted from the GSM-R cell I / Q signal to obtain the FCCH single-frequency signal; The instantaneous phase sequence is obtained by performing four-quadrant arctangent calculation on each sampling point in the FCCH single-frequency signal; The instantaneous phase sequence is unwound to obtain the measured phase sequence of the FCCH signal.

10. The method as described in claim 1, characterized in that, The statistical characteristics include the mean and variance; Based on the statistical characteristics of the instantaneous phase difference sequence, the GSM-R network utilization quality assessment results are obtained, including: The weighted fusion result of the average value and the variance is determined as the GSM-R network operation quality evaluation index value; The level of GSM-R network operation quality is assessed based on the relationship between the GSM-R network operation quality evaluation index value and the preset index threshold.

11. The method as described in claim 1, characterized in that, Acquire GSM-R cell I / Q signals along the railway line, including: The broadband I / Q signals along the railway line are channelized using a multiphase filtering algorithm. Based on the configuration information of the GSM-R cell operating parameters and the mileage information of the railway line, the GSM-R cell I / Q signal is extracted from the channelized I / Q signal.

12. A GSM-R network application quality assessment device, characterized in that, include: The GSM-R signal acquisition module is used to acquire in-phase orthogonal I / Q signals from GSM-R cells along the railway line. The FCCH signal location module is used to: identify the arrival time of the frequency correction channel (FCCH) signal in the GSM-R cell I / Q signal based on the timing characteristics of the GSM-R multiframe; The FCCH phase acquisition module is used to: extract signal segments from the GSM-R cell I / Q signals based on the arrival time of the FCCH signal, and obtain the measured phase sequence of the FCCH signal; The FCCH phase distortion analysis module is used to: calculate the instantaneous phase difference between each sampling point in the measured phase sequence of the FCCH signal and the ideal phase model of the FCCH, and obtain an instantaneous phase difference sequence characterizing the degree of FCCH phase distortion; the ideal phase model of the FCCH is constructed according to the FCCH standard parameters of GSM-R; The network usage quality assessment module is used to obtain the GSM-R network usage quality assessment result based on the statistical characteristics of the instantaneous phase difference sequence.

13. A computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the method of any one of claims 1 to 11.

14. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, implements the method of any one of claims 1 to 11.

15. A computer program product, characterized in that, The computer program product includes a computer program that, when executed by a processor, implements the method of any one of claims 1 to 11.

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