Communication quality assessment method and device
By performing polygonal vector modeling and electromagnetic calculations on the urban environment, combined with PSK and QAM modulation, the problem of insufficient accuracy in communication quality assessment in urban environments was solved, achieving high-precision communication quality assessment and providing a basis for base station deployment and communication equipment location selection.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- CHINESE PEOPLES LIBERATION ARMY UNIT 32802
- Filing Date
- 2026-02-13
- Publication Date
- 2026-05-01
AI Technical Summary
In current technologies for assessing communication quality in urban environments, indicators such as transmission interruption probability and bit error rate lack integration with the actual environment, resulting in insufficient accuracy and failing to meet the growing accuracy requirements of electromagnetic calculation models.
By modeling the area to be evaluated, a polygonal vector model is obtained. Line-of-sight and non-line-of-sight field models are processed, spatial received power coverage and bit error rate are calculated, and communication quality evaluation results are derived by combining common PSK and QAM modulation.
It achieves high-precision communication quality assessment at any location in a complex urban environment under Gaussian white noise interference, applicable to any urban environment, and provides a scientific reference for base station deployment and communication device location selection.
Smart Images
Figure CN121968172A_ABST
Abstract
Description
A method and apparatus for evaluating communication quality Technical Field
[0001] This invention relates to the field of radio wave propagation effects and communication quality assessment technology, and in particular to a communication quality assessment method and apparatus. Background Technology
[0002] The paper "Research on Network State Quality Assessment and Prediction of LTE-M Vehicle-to-Ground Wireless Communication System" discloses a network state quality assessment method based on support vector machines. It focuses on the assessment and prediction of network state quality in LTE-M vehicle-to-ground wireless communication systems. Through optimization analysis of parameters such as track gauge and station spacing, and performance comparison between scheduling and handover algorithms, it employs a deep learning prediction method, fully utilizing the correlation between KPI data and time series to achieve prediction and optimization of future network state quality. However, it relies on a large dataset for training, requiring significant manpower and time to collect large amounts of measured data for each different scenario, resulting in poor flexibility. The paper "Research on Fading of Mobile TV Signal Transmission" analyzes the impact of modulation methods on signal fading and, combined with wireless signal transmission models such as the Cost231-Walfisch-Ikegami model, derives the relationship between signal transmit power and received signal bit error rate under different modulation methods. However, this method only considers statistical models and does not account for different radio wave propagation effects in specific environments, leading to a root mean square error (RMSE) of over 8dB in practical environments, which cannot meet the increasing accuracy requirements of electromagnetic calculation models. Other papers disclose a method based on... In small-scale fading channels, a communication bit error rate (BER) assessment technique involving Gaussian white noise interference is used. This involves calculating the SER expressions for different modulation schemes using Mellin transform, then calculating the ergodic capacity of different spectra, and finally evaluating the results using the Monte Carlo method. However, while this method considers the signal-to-noise ratio (SNR) changes caused by small-scale fading, it still fails to account for the impact of large-scale fading at different locations due to the actual environment, thus failing to provide a basis for practical communication quality assessment. Summary of the Invention
[0003] The technical problem to be solved by the present invention is to provide a communication quality assessment method and apparatus, which overcomes the shortcomings of the prior art in that communication indicators such as transmission interruption probability and bit error rate for urban environment communication quality are not combined with the actual environment.
[0004] To address the aforementioned technical problems, a first aspect of this invention discloses a communication quality assessment method, the method comprising: S1, modeling the region to be assessed to obtain a polygonal vector model; S2, processing the polygonal vector model to obtain a spatial received power coverage prediction result; S3, processing the polygonal vector model to obtain a bit error rate assessment result; and S4, integrating the spatial received power coverage prediction result and the bit error rate assessment result to obtain a communication quality assessment result.
[0005] As an optional implementation, in the first aspect of the present invention, the step of modeling the area to be evaluated to obtain a polygon vector model includes: S11, obtaining a satellite map of the area to be evaluated; S12, processing the satellite map to obtain an OSM file model; and S13, converting the OSM file model to obtain a polygon vector model.
[0006] As an optional implementation, in the first aspect of the present invention, processing the polygonal vector model to obtain a spatial received power coverage prediction result includes: S21, processing the polygonal vector model to obtain a line-of-sight (LOS) field model; S22, processing the LOS field model to obtain a LOS transmission loss; the LOS transmission loss includes UHF frequency LOS transmission loss and SHF band LOS transmission loss; S23, processing the polygonal vector model to obtain a non-line-of-sight (NOS) field model; S24, processing the NOS field model to obtain a NOS transmission loss; and S25, integrating the LOS transmission loss and the NOS transmission loss to obtain a spatial received power coverage prediction result.
[0007] As an optional implementation, in the first aspect of the present invention, the processing of the line-of-sight site model to obtain line-of-sight transmission loss includes: S221, processing the ground clearance of the transmitting antenna and the ground clearance of the receiving antenna to obtain UHF frequency line-of-sight transmission loss; S222, processing the ground clearance of the transmitting antenna, the ground clearance of the receiving antenna, and the effective road height to obtain SHF band line-of-sight transmission loss.
[0008] As an optional implementation, in the first aspect of the present invention, the processing of the transmission antenna height above the ground and the receiving antenna height above the ground to obtain the UHF frequency line-of-sight transmission loss includes: S2211, processing the transmission antenna height above the ground and the receiving antenna height above the ground to obtain the first inflection point distance; the expression for the first inflection point distance is: In the formula, It is the distance to the first inflection point. It's the wavelength. Indicates the height of the transmitting antenna above the ground. S2212, Processing the heights of the transmitting and receiving antennas above the ground to obtain the first basic transmission loss value at the inflection point; The expression for the first basic transmission loss value at the inflection point is: In the formula, The first basic transmission loss value is located at the inflection point; S2213, the distance to the first inflection point and the first basic transmission loss value at the inflection point are processed to obtain the line-of-sight transmission loss; the expression for the line-of-sight transmission loss is: in, For line-of-sight transmission loss, The ITU recommends a 20 dB value for fading margin, but this may vary depending on the actual environment. , The attenuation coefficient is given by the ITU with an upper bound of 40 and a lower bound of 20. This is the distance between the transmitting antenna and the receiving antenna.
[0009] As an optional implementation, in the first aspect of the present invention, the processing of the transmitting antenna height above the ground, the receiving antenna height above the ground, and the effective road height to obtain the SHF band line-of-sight transmission loss includes: S2221, processing the transmitting antenna height above the ground, the receiving antenna height above the ground, and the effective road height to obtain the second inflection point distance; the expression for the second inflection point distance is: In the formula, The distance to the second inflection point. The effective road height; S2222, the height of the transmitting antenna above the ground, the height of the receiving antenna above the ground, and the effective road height are processed to obtain the second basic transmission loss value at the inflection point; the expression for the second basic transmission loss value at the inflection point is: in, The second basic transmission loss value at the inflection point; S2223, when the height of the transmitting antenna above the ground and the height of the receiving antenna above the ground are greater than the effective road height, the distance to the second inflection point and the second basic transmission loss value at the inflection point are processed to obtain the line-of-sight transmission loss of the first SHF band; the expression for the line-of-sight transmission loss of the first SHF band is: In the formula, The first SHF band line-of-sight transmission loss; S2224, when the height of the transmitting antenna above the ground and the height of the receiving antenna above the ground are less than the effective road height, and the distance between the transmitting antenna and the receiving antenna is greater than a preset threshold, the preset basic transmission loss is processed to obtain the second SHF band line-of-sight transmission loss; the expression for the second SHF band line-of-sight transmission loss is: In the formula, For the line-of-sight transmission loss in the second SHF band, For basic transmission loss, , The threshold is set to a preset threshold. In step S2225, the line-of-sight transmission loss of the first SHF band and the line-of-sight transmission loss of the second SHF band are integrated to obtain the line-of-sight transmission loss of the SHF band.
[0010] As an optional implementation, in the first aspect of the present invention, processing the non-line-of-sight site model to obtain the non-line-of-sight transmission loss includes: S241, calculating the distance from the transmission point to the intersection. Distance from the receiving point to the intersection Processing was performed to obtain the first loss. S242, process the preset corner loss to obtain the second loss. S243, Basic transmission loss on Loss streets The first loss The second loss Processing is performed to obtain the non-line-of-sight transmission loss. The non-line-of-sight transmission loss The expression is: in, , , It's frequency. This represents the percentage of the area covered by buildings.
[0011] A second aspect of this invention discloses a communication quality assessment device, comprising: a model building module for modeling an area to be assessed to obtain a polygonal vector model; a received power coverage prediction module for processing the polygonal vector model to obtain a spatial received power coverage prediction result; a bit error rate assessment module for processing the polygonal vector model to obtain a bit error rate assessment result; and a communication quality assessment module for integrating the spatial received power coverage prediction result and the bit error rate assessment result to obtain a communication quality assessment result.
[0012] As an optional implementation, in the second aspect of the present invention, the step of modeling the area to be evaluated to obtain a polygon vector model includes: S11, obtaining a satellite map of the area to be evaluated; S12, processing the satellite map to obtain an OSM file model; and S13, converting the OSM file model to obtain a polygon vector model.
[0013] As an optional implementation, in the second aspect of the present invention, processing the polygonal vector model to obtain a spatial received power coverage prediction result includes: S21, processing the polygonal vector model to obtain a line-of-sight field model; S22, processing the line-of-sight field model to obtain a line-of-sight transmission loss; the line-of-sight transmission loss includes UHF frequency line-of-sight transmission loss and SHF band line-of-sight transmission loss; S23, processing the polygonal vector model to obtain a non-line-of-sight field model; S24, processing the non-line-of-sight field model to obtain a non-line-of-sight transmission loss; S25, integrating the line-of-sight transmission loss and the non-line-of-sight transmission loss to obtain a spatial received power coverage prediction result.
[0014] As an optional implementation, in the second aspect of the present invention, the processing of the line-of-sight site model to obtain line-of-sight transmission loss includes: S221, processing the height of the transmitting antenna above the ground and the height of the receiving antenna above the ground to obtain the UHF frequency line-of-sight transmission loss; S222, processing the height of the transmitting antenna above the ground, the height of the receiving antenna above the ground, and the effective road height to obtain the SHF band line-of-sight transmission loss.
[0015] As an optional implementation, in the second aspect of the present invention, the processing of the transmission antenna height above the ground and the receiving antenna height above the ground to obtain the UHF frequency line-of-sight transmission loss includes: S2211, processing the transmission antenna height above the ground and the receiving antenna height above the ground to obtain the first inflection point distance; the expression for the first inflection point distance is: In the formula, It is the distance to the first inflection point. It's the wavelength. Indicates the height of the transmitting antenna above the ground. S2212, Processing the heights of the transmitting and receiving antennas above the ground to obtain the first basic transmission loss value at the inflection point; The expression for the first basic transmission loss value at the inflection point is: In the formula, The first basic transmission loss value is located at the inflection point; S2213, the distance to the first inflection point and the first basic transmission loss value at the inflection point are processed to obtain the line-of-sight transmission loss; the expression for the line-of-sight transmission loss is: in, For line-of-sight transmission loss, The ITU recommends a 20 dB value for fading margin, but this may vary depending on the actual environment. , The attenuation coefficient is given by the ITU with an upper bound of 40 and a lower bound of 20. This is the distance between the transmitting antenna and the receiving antenna.
[0016] As an optional implementation, in the second aspect of the present invention, the processing of the transmitting antenna height above the ground, the receiving antenna height above the ground, and the effective road height to obtain the SHF band line-of-sight transmission loss includes: S2221, processing the transmitting antenna height above the ground, the receiving antenna height above the ground, and the effective road height to obtain the second inflection point distance; the expression for the second inflection point distance is: In the formula, The distance to the second inflection point. The effective road height; S2222, the height of the transmitting antenna above the ground, the height of the receiving antenna above the ground, and the effective road height are processed to obtain the second basic transmission loss value at the inflection point; the expression for the second basic transmission loss value at the inflection point is: in, The second basic transmission loss value at the inflection point; S2223, when the height of the transmitting antenna above the ground and the height of the receiving antenna above the ground are greater than the effective road height, the distance to the second inflection point and the second basic transmission loss value at the inflection point are processed to obtain the line-of-sight transmission loss of the first SHF band; the expression for the line-of-sight transmission loss of the first SHF band is: In the formula, The first SHF band line-of-sight transmission loss; S2224, when the height of the transmitting antenna above the ground and the height of the receiving antenna above the ground are less than the effective road height, and the distance between the transmitting antenna and the receiving antenna is greater than a preset threshold, the preset basic transmission loss is processed to obtain the second SHF band line-of-sight transmission loss; the expression for the second SHF band line-of-sight transmission loss is: In the formula, For the line-of-sight transmission loss in the second SHF band, For basic transmission loss, , The threshold is set to a preset threshold. In step S2225, the line-of-sight transmission loss of the first SHF band and the line-of-sight transmission loss of the second SHF band are integrated to obtain the line-of-sight transmission loss of the SHF band.
[0017] As an optional implementation, in the second aspect of the present invention, processing the non-line-of-sight site model to obtain the non-line-of-sight transmission loss includes: S241, calculating the distance from the transmission point to the intersection. Distance from the receiving point to the intersection Processing was performed to obtain the first loss. S242, process the preset corner loss to obtain the second loss. S243, Basic transmission loss on Loss streets The first loss The second loss Processing is performed to obtain the non-line-of-sight transmission loss. The non-line-of-sight transmission loss The expression is: in, , , It's frequency. This represents the percentage of the area covered by buildings.
[0018] A third aspect of the present invention discloses another communication quality assessment apparatus, the apparatus comprising: a memory storing executable program code; a processor coupled to the memory; the processor calling the executable program code stored in the memory to execute some or all of the steps in the communication quality assessment method disclosed in the first aspect of the present invention.
[0019] The fourth aspect of the present invention discloses a computer-storable medium storing computer instructions, which, when invoked, are used to execute some or all of the steps in the communication quality assessment method disclosed in the first aspect of the present invention.
[0020] Compared with the prior art, the embodiments of the present invention have the following beneficial effects: The present invention discloses a communication quality assessment method, which is applicable to communication quality assessment under Gaussian white noise interference based on urban radio wave propagation characteristics. It can achieve high-precision assessment of communication quality under Gaussian white noise interference at any location in a complex urban environment without the need for fitting and correction of a large number of measured results. It can be applied to any urban environment and can provide a scientific reference for individuals and enterprises (such as operators) to deploy base stations and select communication equipment locations. Attached Figure Description
[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0022] Figure 1 is a flowchart illustrating a communication quality assessment method disclosed in an embodiment of the present invention; Figure 2 is a schematic diagram of the OpenStreetMap interface disclosed in an embodiment of the present invention; Figure 3 is the OSM file format disclosed in an embodiment of the present invention; Figure 4 is a two-dimensional model of the OSM file after UTM projection disclosed in an embodiment of the present invention; Figure 5 is a schematic diagram of a typical propagation scenario in a micro-cell in a dense urban area disclosed in an embodiment of the present invention; Figure 6 is a schematic diagram of a building corner in a micro-cell disclosed in an embodiment of the present invention; Figure 7 is the relationship between the error probability of M-PSK modulated messages and the interference noise power disclosed in an embodiment of the present invention; Figure 8 is the relationship between the error probability of M-QAM modulated messages and the interference noise power disclosed in an embodiment of the present invention; Figure 9 is the interference signal received power coverage prediction for a certain urban area disclosed in an embodiment of the present invention; Figure 10 is the bit error rate coverage prediction for a specified area in a certain urban area disclosed in an embodiment of the present invention. Figure 11 is a judgment diagram of interference effect in a certain urban area disclosed in an embodiment of the present invention; Figure 12 is a Wi-Fi signal spectrum monitoring diagram disclosed in an embodiment of the present invention; Figure 13 is a Wi-Fi signal spectrum monitoring diagram after sending interference signals disclosed in an embodiment of the present invention; Figure 14 is a comparison of Wi-Fi signal monitoring before and after interference disclosed in an embodiment of the present invention; Figure 15 is the experimental equipment related to the preliminary test of unmanned vehicles and drones disclosed in an embodiment of the present invention; Figure 16 is a normalized IQ constellation diagram of interference signals disclosed in an embodiment of the present invention; Figure 17 is a comparison diagram of 700MHz road test data and simulation results disclosed in an embodiment of the present invention; Figure 18 is a comparison diagram of 2700MHz road test data and simulation results disclosed in an embodiment of the present invention; Figure 19 is a structural schematic diagram of a communication quality assessment device disclosed in an embodiment of the present invention; Figure 20 is a structural schematic diagram of another communication quality assessment device disclosed in an embodiment of the present invention. Detailed Implementation
[0023] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0024] The terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this invention are used to distinguish different objects, not to describe a specific order. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, apparatus, product, or device that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products, or devices.
[0025] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of the invention. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.
[0026] This invention discloses a communication quality assessment method and apparatus. The method includes modeling the area to be assessed to obtain a polygonal vector model; processing the polygonal vector model to obtain a spatial received power coverage prediction result; processing the polygonal vector model to obtain a bit error rate (BER) assessment result; and integrating the spatial received power coverage prediction result and the BER assessment result to obtain a communication quality assessment result. This invention can achieve high-precision assessment of communication quality at any location in a complex urban environment under Gaussian white noise interference without requiring extensive fitting and correction of measured results. It is applicable to any urban environment and can provide a scientific reference for base station deployment and communication device location selection for individuals and enterprises. Detailed descriptions follow.
[0027] Please refer to Figure 1 for Example 1. Figure 1 is a flowchart illustrating a communication quality assessment method disclosed in this embodiment of the invention. The communication quality assessment method described in Figure 1 is applied to the field of radio wave propagation effects and communication quality assessment technology, and this embodiment of the invention does not limit its application. As shown in Figure 1, the communication quality assessment method may include the following operations: S1, modeling the area to be assessed to obtain a polygonal vector model; S2, processing the polygonal vector model to obtain a spatial received power coverage prediction result; S3, processing the polygonal vector model to obtain a bit error rate assessment result; S4, integrating the spatial received power coverage prediction result and the bit error rate assessment result to obtain a communication quality assessment result.
[0028] Optionally, the step of modeling the area to be evaluated to obtain a polygon vector model includes: S11, obtaining a satellite map of the area to be evaluated; S12, processing the satellite map to obtain an OSM file model; and S13, converting the OSM file model to obtain a polygon vector model.
[0029] Optionally, processing the polygonal vector model to obtain the spatial received power coverage prediction result includes: S21, processing the polygonal vector model to obtain a line-of-sight field model; S22, processing the line-of-sight field model to obtain line-of-sight transmission loss; the line-of-sight transmission loss includes UHF frequency line-of-sight transmission loss and SHF band line-of-sight transmission loss; S23, processing the polygonal vector model to obtain a non-line-of-sight field model; S24, processing the non-line-of-sight field model to obtain a non-line-of-sight transmission loss; S25, integrating the line-of-sight transmission loss and the non-line-of-sight transmission loss to obtain the spatial received power coverage prediction result.
[0030] Optionally, the process of processing the line-of-sight site model to obtain the line-of-sight transmission loss includes: S221, processing the height of the transmitting antenna above the ground and the height of the receiving antenna above the ground to obtain the UHF frequency line-of-sight transmission loss; S222, processing the height of the transmitting antenna above the ground, the height of the receiving antenna above the ground, and the effective road height to obtain the SHF band line-of-sight transmission loss.
[0031] Optionally, the step of processing the heights of the transmitting antenna and the receiving antenna above the ground to obtain the UHF frequency line-of-sight transmission loss includes: S2211, processing the heights of the transmitting antenna and the receiving antenna above the ground to obtain the first inflection point distance; the expression for the first inflection point distance is: In the formula, It is the distance to the first inflection point. It's the wavelength. Indicates the height of the transmitting antenna above the ground. S2212, Processing the heights of the transmitting and receiving antennas above the ground to obtain the first basic transmission loss value at the inflection point; The expression for the first basic transmission loss value at the inflection point is: In the formula, The first basic transmission loss value is located at the inflection point; S2213, the distance to the first inflection point and the first basic transmission loss value at the inflection point are processed to obtain the line-of-sight transmission loss; the expression for the line-of-sight transmission loss is: in, For line-of-sight transmission loss, The ITU recommends a 20 dB value for fading margin, but this may vary depending on the actual environment. , The attenuation coefficient is given by the ITU with an upper bound of 40 and a lower bound of 20. This is the distance between the transmitting antenna and the receiving antenna.
[0032] Optionally, the step of processing the transmission antenna height above the ground, the receiving antenna height above the ground, and the effective road height to obtain the SHF band line-of-sight transmission loss includes: S2221, processing the transmission antenna height above the ground, the receiving antenna height above the ground, and the effective road height to obtain the second inflection point distance; the expression for the second inflection point distance is: In the formula, The distance to the second inflection point. The effective road height; S2222, the height of the transmitting antenna above the ground, the height of the receiving antenna above the ground, and the effective road height are processed to obtain the second basic transmission loss value at the inflection point; the expression for the second basic transmission loss value at the inflection point is: in, The second basic transmission loss value at the inflection point; S2223, when the height of the transmitting antenna above the ground and the height of the receiving antenna above the ground are greater than the effective road height, the distance to the second inflection point and the second basic transmission loss value at the inflection point are processed to obtain the line-of-sight transmission loss of the first SHF band; the expression for the line-of-sight transmission loss of the first SHF band is: In the formula, The first SHF band line-of-sight transmission loss; S2224, when the height of the transmitting antenna above the ground and the height of the receiving antenna above the ground are less than the effective road height, and the distance between the transmitting antenna and the receiving antenna is greater than a preset threshold, the preset basic transmission loss is processed to obtain the second SHF band line-of-sight transmission loss; the expression for the second SHF band line-of-sight transmission loss is: In the formula, For the line-of-sight transmission loss in the second SHF band, For basic transmission loss, , The threshold is set to a preset threshold. In step S2225, the line-of-sight transmission loss of the first SHF band and the line-of-sight transmission loss of the second SHF band are integrated to obtain the line-of-sight transmission loss of the SHF band.
[0033] Optionally, processing the non-line-of-sight site model to obtain the non-line-of-sight transmission loss includes: S241, calculating the distance from the transmission point to the intersection. Distance from the receiving point to the intersection Processing was performed to obtain the first loss. ;for ,when hour: when hour, , This indicates the street width (m) at the location of the launch point. This indicates the street width (m) at the location of the receiving point. Typically 30m; S242, the preset corner loss is processed to obtain the second loss. ;for ,when hour: when hour: , The reference value is 20 dB in urban environments and 30 dB in residential environments.
[0034] S243, Basic transmission loss on LosS streets The first loss The second loss Processing is performed to obtain the non-line-of-sight transmission loss. ; Is when Basic transmission loss on Loss streets; the non-line-of-sight transmission loss The expression is: in, , , It's frequency. This represents the percentage of the area covered by buildings. Indicates the curvature of a street corner.
[0035] S3, the specific method for processing the polygonal vector model to obtain the bit error rate assessment result is as follows: Considering common PSK and QAM modulation, for PSK: since messages are transmitted with equal probability, the decision domain of the received signal is based on minimum distance detection. When the interference signal is Gaussian white noise, the received signal... It can be represented as: It is variance The mean values are respectively Independent Gaussian random variables with and 0, It is a constant. ,therefore: For probability, As a preset constant, For time variables, corresponding to polar coordinates: From this, we can deduce that... , Joint probability density distribution: right Integral, to obtain The marginal PDF is: According to the maximum likelihood ratio decision principle, for symbol errors, the Euclidean distance between the IQ coordinates of the receiver point and the error interval on the constellation diagram is smaller than its Euclidean distance to the correct interval. For PSK decision, we only care about the angle of the IQ data on the constellation diagram, thus obtaining the message error probability of M-PSK: For QAM, the research approach is the same as for M-PSK. The waveform of QAM can be represented as: by , As a set of orthogonal bases, the signal is represented as follows: Mapped to a constellation chart: Average bit energy: Minimum symbol distance: The message error probability of M-QAM under Gaussian white noise is obtained as follows: As can be seen, this invention discloses a communication quality assessment method applicable to communication quality assessment under Gaussian white noise interference based on urban radio wave propagation characteristics. It can achieve high-precision assessment of communication quality at any location in a complex urban environment under Gaussian white noise interference without requiring extensive fitting and correction of measured results. It is applicable to any urban environment and can provide a scientific reference for individuals and enterprises (such as operators) in base station deployment and communication equipment location selection.
[0036] Example 2 The technical solution of this example consists of three parts: first, urban environment polygon vector modeling based on OpenStreetMap; second, spatial received power coverage prediction based on ITU-1411; and third, bit error rate assessment based on electromagnetic calculation results.
[0037] 1. Urban Environment Modeling Based on OpenStreetMap: OpenStreetMap (OSM) is a collaborative online map project that allows for the creation of freely editable world maps, with the goal of providing convenient navigation options for inexpensive mobile devices. By delineating satellite imagery, polygons can be defined for various elements on the map, as shown in Figure 2. After editing, the data can be exported as an .osm file, containing the latitude and longitude coordinates of each point in the polygon, as shown in Figure 3. After UTM projection transformation, the data provides building projections and heights for subsequent ITU calculations of building losses, as shown in Figure 4.
[0038] 2. Spatial Received Power Coverage Prediction Based on ITU-1411: This study investigates scenarios where both transmitting and receiving antennas are located below the roof, based on ITU recommendations. A schematic diagram of the transmitting and receiving antennas is shown in Figure 5. Indicates the height of the transmitting antenna above the ground. The height of the receiving antenna above the ground is indicated. Due to experimental limitations, the transmitting antenna of this invention could not be erected on the highest rooftop during the actual experiment. The following discussion on the path loss prediction model assumes that the height of the transmitting and receiving antennas is less than the maximum rooftop height.
[0039] (1) Specific site model for line-of-sight (LoS) For electromagnetic wave propagation in the UHF (Ultra High Frequency) frequency range, the basic transmission loss can be represented by two slopes and one inflection point. The specific formula is as follows: in It is the distance between the inflection points, and is calculated by the following formula: in It is the wavelength (m). The lower bound is based on the two-ray plane geodetic reflection model.
[0040] The fundamental transmission loss value at the inflection point is defined as: The ITU recommends a 20 dB value for fading margin. However, this may vary depending on the specific environment. , The attenuation coefficient is given by the ITU with an upper bound of 40 and a lower bound of 20.
[0041] In the SHF band, when the path length is as high as approximately 1 km, road traffic will affect the effective road height and consequently the inflection point distance. It can be estimated using the following formula: (4) The effective road height is derived from research subjects such as vehicles on the road and pedestrians near the road. It depends on the road's traffic flow. The ITU provides reference values for effective road height during peak and off-peak hours. The values are taken from daytime and nighttime measurements, corresponding to peak and off-peak traffic conditions, respectively. Peak traffic flow corresponds to 10-20% road vehicle coverage and 0.2-1% pedestrian sidewalk occupancy. Off-peak traffic flow refers to 0.1-0.5% road coverage and less than 0.001% pedestrian sidewalk occupancy.
[0042] when At that time, the basic transmission loss of the SHF band can be calculated using formula (1). It is given by the following formula: On the other hand, when or There are no inflection points. When two terminals are close together... The basic transmission loss is similar to the basic propagation loss in the UHF range. When the two terminals are far apart, the propagation characteristics cause the attenuation coefficient to be a power of three. The approximate lower bound is given by the following equation: The approximate upper bound is given by the following equation: Basic transmission loss Defined as: The empirical value is generally determined to be 20m. Based on ITU measurements, the median value is given by the following formula: When the frequency is above approximately 10 GHz, the inflection point distance in formula (24) This is far greater than the expected maximum cell radius (500m). This means that there is no expected 4th power regularity in this frequency band, but rather a free-space regularity with path loss of approximately 1.9-2.2 powers.
[0043] (2) Specific site model for non-line-of-sight (NLoS) For the NLoS case where both antennas are below the height of the roof, diffraction and reflection waves at the corner of the street intersection must be considered. A typical propagation scenario of the NLOS path in a microcell is shown in Figure 6.
[0044] In Figure 6, This indicates the street width (m) at the location of the launch point. This indicates the street width (m) at the location of the receiving point. This represents the distance (m) from the launch point to the intersection. This indicates the distance from the receiving point to the intersection. The radian of the street corner is indicated by STN, which stands for station and indicates the location of the transmitting and receiving points.
[0045] The basic transmission loss characteristics can be divided into two parts: the corner loss region and the NLoS region. The corner loss region extends from a point 1m away from the edge of the Loss Street. After entering NLoS street, corner damage occurred. Represented as Additional attenuation due to distance, the NLoS region is located outside the corner loss region, and a coefficient parameter is applied. By using the method shown in Figure 7 , and The area outside the corner can be calculated using the following formula. Overall basic transmission loss: for ,when hour: when hour: for ,when hour: when hour, .
[0046] Here Is when The basic transmission loss on the LoS street is given by formula (12). The reference value is 20 dB in urban environments and 30 dB in residential environments. In both environments, it is generally 30m.
[0047] In equation (13), when the four corners of the intersection are wedge-shaped buildings, If the four corners of the intersection are sloping buildings, then Calculated according to equation (14). Because the mirror reflection path of the sloping building significantly affects the basic transmission loss in the non-line-of-sight area.
[0048] in This refers to frequency, measured in megahertz (MHz). In addition, a correction term for building absorption loss is constructed based on the deterministic formula for building absorption loss: In the formula: For constant terms; This is the loss coefficient; The percentage of the area covered by buildings is calculated using the following formula: in, This indicates the distance the transmitting and receiving antenna lines pass through the building. This represents the total distance between the transmitting and receiving antennas. The correction term constructed from formula (17) is then fitted with parameters based on measured data. The average value was uniformly set to 20.757. The comparison between the final constructed received power prediction model and the actual results is shown in Figures 18 and 19.
[0049] 3. Communication quality assessment technique based on received power coverage prediction model: Considering common PSK and QAM modulation, for PSK: since messages are transmitted with equal probability, the decision domain of the received signal is based on minimum distance detection. When the interference signal is Gaussian white noise, the received signal can be expressed as: It is variance The mean values are respectively Independent Gaussian random variables with and 0, These are mutually independent Gaussian random variables with zero mean, corresponding to the projections of noise onto the two basis functions, i.e. ... Noise power per hertz bandwidth; The average energy of the transmitted symbols is the square root; therefore: Corresponding to polar coordinates: From this, we can deduce that... , Joint probability density distribution: right Integral, to obtain The marginal PDF is: For the signal-to-noise ratio per symbol, according to the maximum likelihood ratio decision principle, the Euclidean distance between the IQ coordinates of the receiver point and the error interval on the constellation diagram is smaller than its Euclidean distance to the correct interval. For PSK decision, only the angle of the IQ data on the constellation diagram is considered, thus obtaining the message error probability of M-PSK: M is the modulation order; the relationship between the bit error rate and signal-to-noise ratio under M-PSK modulation corresponding to equation (22) is shown in Figure 6.
[0050] For QAM, the research approach is the same as for M-PSK; the waveform of QAM... It can be represented as: This represents the amplitude of the m-th symbol in the in-phase branch, corresponding to the horizontal axis of the constellation diagram. This represents the amplitude of the m-th symbol in the orthogonal branch, corresponding to the vertical axis of the constellation diagram. This refers to the baseband shaping pulse (or the impulse response of the transmit filter), used to limit signal bandwidth and suppress inter-symbol interference (ISI). Common examples include raised cosine roll-off filters and rectangular pulses. Re denotes the carrier frequency. Re denotes taking the real part, and t denotes time. , As a set of orthogonal bases, the signal is represented as follows: express The energy, mapped onto the constellation chart : Average bit energy : Minimum symbol distance : Obtain the M-QAM message error probability under Gaussian white noise. : In the formula, The Q-function is a Gaussian function used to calculate the tail probability under a Gaussian distribution and is a core function in bit error rate analysis. The average energy per bit, usually measured in joules. Figure 8 shows the one-sided power spectral density of additive white Gaussian noise (AWGN), expressed in W / Hz, representing the noise power within each Hertz bandwidth. The relationship between bit error rate and signal-to-noise ratio under M-QAM modulation is illustrated in Figure 8. Specifically, in a real-world urban scenario, taking GPS signals as an example: GPS signals are very weak, already below the natural noise floor near the ground. Assuming a commonly used passive antenna with a 3-6 dB gain is used for reception in an open area, the total received level can reach a maximum of approximately -120 dBm. Civilian GPS signals are spread spectrum signals with a frequency of 1575 MHz and a bandwidth of 2.046 MHz, with a spread spectrum gain of 43 dB and Cb / N0 considered at 6 dB. While any form of interference can be effective if it is sufficiently large, the effectiveness of interference in certain frequency bands is poor due to the high spread spectrum gain. Among easily implemented methods, full-band noise interference is more advantageous; however, when the bit error rate exceeds 30% under the following conditions, normal GPS data cannot be obtained: The bandwidth of the interference signal is equal to or greater than 2.046MHz, covering the entire frequency band of the GPS signal.
[0051] After the interference signal is received by the GPS antenna, its total power level is higher than -83dBm.
[0052] The main lobe of a GPS antenna points towards the sky, providing some isolation from ground-based interference. The degree of isolation depends on the antenna's quality, installation method, structure, and materials, typically providing 30-40 dB of isolation. However, if the antenna's directivity is poor or the installation is not vertical enough, the isolation will decrease. Assuming the GPS antenna gain to the ground-based attacker (interference source) is -40 dB, and the gain to the sky meets the requirements for a normal GPS receiving antenna (i.e., the total received level reaches -120 dBm), and the interference transmitter's antenna gain is 0 dB, then according to the free-space loss formula, the required transmit power is... yes: G is the total gain of the transmit and receive antennas. Here, Receive Power (dBm) represents the power of the radio frequency signal received at the receiving antenna port, d is the distance between the transmitting and receiving ends (usually in kilometers), and f is the carrier frequency. The above formula shows that, for free-space loss, if the interference bandwidth is moderate, only 2W of interference signal transmission power is needed to suppress GPS signals within a 100-meter range. Mapped to the field of electromagnetic calculations, if the comprehensive simulation calculation of the interference source's transmitted signal at the GPS antenna is greater than 2W, the GPS signal can be considered successfully interfered with. However, in the complex urban environment, directly applying the free-space loss formula does not achieve the required accuracy for precise deduction. Therefore, based on the ITU's received power coverage prediction method, the power coverage prediction for a specific area with an interference signal transmission power of 2W and an interference antenna of dipole type is simulated, as shown in Figure 9. The bit error rate of the GPS signal in each area is calculated based on 16QAM, as shown in Figure 10. Finally, the normal communication area and communication interruption area of the GPS signal are calculated, as shown in Figure 11.
[0053] Example 3 selects a measurement site for the communication equipment and conducts verification tests on the equipment's resistance to Gaussian white noise interference and electromagnetic calculation accuracy. First, the verification test on the equipment's resistance to Gaussian white noise interference is conducted. Two mobile phones are prepared: one is used to simulate a Wi-Fi signal by turning on a hotspot, and the other is used as the verification object for the interference resistance. Since it is impossible to directly measure quantitative indicators such as the phone's bit error rate, this patent uses the phone's ability to receive and connect to the hotspot signal as the evaluation standard for interference resistance.
[0054] The spectrum of the uninterrupted Wi-Fi signal is shown in Figure 13. Without interference, the average power of the 2.4 GHz Wi-Fi signal is around -70 dBm. After applying Gaussian white noise interference until the Wi-Fi signal becomes unusable, the average power is measured to be approximately -54 dBm, resulting in a calculated JSR of around -16 dB. Corresponding to 16QAM, the bit error rate is 0.456. At this point, Wi-Fi signals in this frequency band are completely unreceived. As can be seen from Figures 13, 14(a), and (b), Wi-Fi in this frequency band is completely suppressed.
[0055] As the distance between the transmitting and receiving antennas increases, the signal-to-interference ratio (SIR) gradually rises, and Wi-Fi begins to recover its normal function, but the data transmission rate remains very low, around tens of kb / s. When entering the NLOS region, the interference signal power drops to a level not much different from the signal power (approximately -65dBm), and the normal communication rate of the 2.4G Wi-Fi signal begins to recover. At this point, the SIR is approximately -7dB, and the theoretical bit error rate is calculated to be around 0.31.
[0056] For large communication devices such as drones and unmanned vehicles, a test site was selected, and symbol-level interference sequences were transmitted through a software-defined radio peripheral platform. Since the bit error rate (BER) and other information of the internal communication modules of the devices were unknown, the success of the interference test was determined by whether the remote control of the unmanned vehicle malfunctioned and whether the image transmission of the drone was interrupted. The relevant test equipment is shown in Figures 15(a) and (b), and the specific constellation diagram of the transmitted interference signal is shown in Figures 16(a), (b), and (c). The test results show that the symbol-level interference signals under different modulation methods have roughly the same suppression effect on unmanned vehicles and drones. The minimum JSR required for the remote control signal of the unmanned vehicle to malfunction is 6 dB, and the minimum JSR for the image transmission signal of the drone is -6 dB.
[0057] A test site was selected, with 700MHz and 2700MHz chosen as the center frequencies. A transmitting antenna approximately 3m high was erected in an open area, and an automated spectrum monitoring platform was mounted on a vehicle as the receiver. Geographic coordinates and power information were recorded in real time along the planned experimental path. Based on spectrum analyzer frequency sweep measurements, simulation results and actual measurements are compared in Figures 17 and 18.
[0058] Please refer to Figure 19 for Embodiment 4. Figure 19 is a schematic diagram of a communication quality assessment device disclosed in this embodiment of the invention. The communication quality assessment device described in Figure 19 is applied to the field of radio wave propagation effects and communication quality assessment technology, and this embodiment of the invention does not limit its application. As shown in Figure 19, the communication quality assessment device may include the following operations: S301, a model building module, used to model the area to be assessed to obtain a polygonal vector model; S302, a received power coverage prediction module, used to process the polygonal vector model to obtain a spatial received power coverage prediction result; S303, a bit error rate assessment module, used to process the polygonal vector model to obtain a bit error rate assessment result; S304, a communication quality assessment module, used to integrate the spatial received power coverage prediction result and the bit error rate assessment result to obtain a communication quality assessment result.
[0059] Please refer to Figure 20 for Embodiment 5. Figure 20 is a schematic diagram of another communication quality assessment device disclosed in this embodiment of the invention. The communication quality assessment device described in Figure 20 is applied to the field of radio wave propagation effects and communication quality assessment technology, and this embodiment of the invention does not limit its application. As shown in Figure 20, the communication quality assessment device may include the following operations: a memory 401 storing executable program code; a processor 402 coupled to the memory 401; the processor 402 calls the executable program code stored in the memory 401 to execute the steps in the communication quality assessment methods described in Embodiments 1, 2, and 3.
[0060] Example 6: This embodiment of the invention discloses a computer-readable storage medium storing a computer program for electronic data interchange, wherein the computer program causes a computer to perform the steps in the communication quality assessment method described in Examples 1, 2, and 3.
[0061] The device embodiments described above are merely illustrative. The modules described as separate components may or may not be physically separate, and the components shown as modules may or may not be physical modules; that is, they may be located in one place or distributed across multiple network modules. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.
[0062] Through the detailed description of the above embodiments, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, including read-only memory (ROM), random access memory (RAM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), one-time programmable read-only memory (OTPROM), electrically-erasable programmable read-only memory (EEPROM), compact disc read-only memory (CD-ROM) or other optical disc storage, disk storage, magnetic tape storage, or any other computer-readable medium that can be used to carry or store data.
[0063] Finally, it should be noted that the communication quality assessment method and apparatus disclosed in the embodiments of the present invention are merely preferred embodiments of the present invention and are only used to illustrate the technical solutions of the present invention, not to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.
Claims
1. A communication quality assessment method, characterized in that, The method includes: S1, modeling the region to be evaluated to obtain a polygonal vector model; S2, processing the polygonal vector model to obtain a spatial received power coverage prediction result; S3, processing the polygonal vector model to obtain a bit error rate evaluation result; S4, integrating the spatial received power coverage prediction result and the bit error rate evaluation result to obtain a communication quality evaluation result.
2. The communication quality assessment method according to claim 1, characterized in that, The process of modeling the area to be evaluated to obtain a polygon vector model includes: S11, obtaining a satellite map of the area to be evaluated; S12, processing the satellite map to obtain an OSM file model; and S13, converting the OSM file model to obtain a polygon vector model.
3. The communication quality assessment method according to claim 1, characterized in that, The process of processing the polygonal vector model to obtain the spatial received power coverage prediction result includes: S21, processing the polygonal vector model to obtain a line-of-sight (LOS) field model; S22, processing the LOS field model to obtain LOS transmission loss, wherein the LOS transmission loss includes UHF frequency LOS transmission loss and SHF band LOS transmission loss; S23, processing the polygonal vector model to obtain a non-line-of-sight (NOS) field model; S24, processing the NOS field model to obtain NOS transmission loss; and S25, integrating the LOS transmission loss and the NOS transmission loss to obtain the spatial received power coverage prediction result.
4. The communication quality assessment method according to claim 3, characterized in that, The process of processing the line-of-sight site model to obtain the line-of-sight transmission loss includes: S221, processing the height of the transmitting antenna above the ground and the height of the receiving antenna above the ground to obtain the UHF frequency line-of-sight transmission loss; S222, processing the height of the transmitting antenna above the ground, the height of the receiving antenna above the ground, and the effective road height to obtain the SHF band line-of-sight transmission loss.
5. The communication quality assessment method according to claim 4, characterized in that, The step of processing the heights of the transmitting antenna and the receiving antenna above the ground to obtain the UHF frequency line-of-sight transmission loss includes: S2211, processing the heights of the transmitting antenna and the receiving antenna above the ground to obtain the first inflection point distance; the expression for the first inflection point distance is: In the formula, It is the distance to the first inflection point. It's the wavelength. Indicates the height of the transmitting antenna above the ground. S2212, Processing the heights of the transmitting and receiving antennas above the ground to obtain the first basic transmission loss value at the inflection point; The expression for the first basic transmission loss value at the inflection point is: In the formula, The first basic transmission loss value is located at the inflection point; S2213, the distance to the first inflection point and the first basic transmission loss value at the inflection point are processed to obtain the line-of-sight transmission loss; the expression for the line-of-sight transmission loss is: in, For line-of-sight transmission loss, The ITU recommends a 20 dB value for fading margin, but this may vary depending on the actual environment. 、 The attenuation coefficient is given by the ITU with an upper bound of 40 and a lower bound of 20. This is the distance between the transmitting antenna and the receiving antenna.
6. The communication quality assessment method according to claim 4, characterized in that, The process of processing the ground clearance of the transmitting antenna, the ground clearance of the receiving antenna, and the effective road height to obtain the line-of-sight transmission loss in the SHF band includes: S2221, processing the ground clearance of the transmitting antenna, the ground clearance of the receiving antenna, and the effective road height to obtain the second inflection point distance; the expression for the second inflection point distance is: In the formula, The distance to the second inflection point. The effective road height; S2222, the height of the transmitting antenna above the ground, the height of the receiving antenna above the ground, and the effective road height are processed to obtain the second basic transmission loss value at the inflection point; the expression for the second basic transmission loss value at the inflection point is: in, The second basic transmission loss value at the inflection point; S2223, when the height of the transmitting antenna above the ground and the height of the receiving antenna above the ground are greater than the effective road height, the distance to the second inflection point and the second basic transmission loss value at the inflection point are processed to obtain the line-of-sight transmission loss of the first SHF band; the expression for the line-of-sight transmission loss of the first SHF band is: In the formula, The first SHF band line-of-sight transmission loss; S2224, when the height of the transmitting antenna above the ground and the height of the receiving antenna above the ground are less than the effective road height, and the distance between the transmitting antenna and the receiving antenna is greater than a preset threshold, the preset basic transmission loss is processed to obtain the second SHF band line-of-sight transmission loss; the expression for the second SHF band line-of-sight transmission loss is: In the formula, For the line-of-sight transmission loss in the second SHF band, For basic transmission loss, ， The threshold is set to a preset threshold. In step S2225, the line-of-sight transmission loss of the first SHF band and the line-of-sight transmission loss of the second SHF band are integrated to obtain the line-of-sight transmission loss of the SHF band.
7. The communication quality assessment method according to claim 4, characterized in that, The process of processing the non-line-of-sight site model to obtain the non-line-of-sight transmission loss includes: S241, calculating the distance from the transmission point to the intersection. Distance from the receiving point to the intersection Processing was performed to obtain the first loss. S242, process the preset corner loss to obtain the second loss. S243, Basic transmission loss on Loss streets The first loss The second loss Processing is performed to obtain the non-line-of-sight transmission loss. The non-line-of-sight transmission loss The expression is: in, ， ， It's frequency. This represents the percentage of the area covered by buildings.
8. A communication quality assessment device, characterized in that, The device includes: a model building module for modeling the region to be evaluated to obtain a polygonal vector model; a received power coverage prediction module for processing the polygonal vector model to obtain a spatial received power coverage prediction result; a bit error rate (BER) evaluation module for processing the polygonal vector model to obtain a BER evaluation result; and a communication quality evaluation module for integrating the spatial received power coverage prediction result and the BER evaluation result to obtain a communication quality evaluation result.
9. A communication quality assessment device, characterized in that, The apparatus includes: a memory storing executable program code; a processor coupled to the memory; the processor calling the executable program code stored in the memory to execute the communication quality assessment method as described in any one of claims 1-7.
10. A computer-storable medium, characterized in that, The computer storage medium stores computer instructions, which, when invoked, are used to execute the communication quality assessment method as described in any one of claims 1-7.