CN110545148A - Meteor trail link planning and predicting method based on GIS (geographic information System) - Google Patents
Meteor trail link planning and predicting method based on GIS (geographic information System) Download PDFInfo
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- CN110545148A CN110545148A CN201910830508.7A CN201910830508A CN110545148A CN 110545148 A CN110545148 A CN 110545148A CN 201910830508 A CN201910830508 A CN 201910830508A CN 110545148 A CN110545148 A CN 110545148A
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B17/00—Monitoring; Testing
- H04B17/30—Monitoring; Testing of propagation channels
- H04B17/373—Predicting channel quality or other radio frequency [RF] parameters
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L41/00—Arrangements for maintenance, administration or management of data switching networks, e.g. of packet switching networks
- H04L41/12—Discovery or management of network topologies
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L41/00—Arrangements for maintenance, administration or management of data switching networks, e.g. of packet switching networks
- H04L41/14—Network analysis or design
- H04L41/145—Network analysis or design involving simulating, designing, planning or modelling of a network
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L41/00—Arrangements for maintenance, administration or management of data switching networks, e.g. of packet switching networks
- H04L41/14—Network analysis or design
- H04L41/147—Network analysis or design for predicting network behaviour
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L43/00—Arrangements for monitoring or testing data switching networks
- H04L43/08—Monitoring or testing based on specific metrics, e.g. QoS, energy consumption or environmental parameters
- H04L43/0805—Monitoring or testing based on specific metrics, e.g. QoS, energy consumption or environmental parameters by checking availability
- H04L43/0811—Monitoring or testing based on specific metrics, e.g. QoS, energy consumption or environmental parameters by checking availability by checking connectivity
Abstract
the invention discloses a meteor trail link planning and predicting method based on a GIS (geographic Information System), belonging to the technical field of communication. The construction process of the meteor trail channel model is relatively complex, simultaneously, the occurrence of meteor phenomenon has strong regionality, the traditional meteor trail link analysis method depends on manual prediction of operation on a graph, the workload is large, the prediction efficiency is low, and the result accuracy is poor. In order to solve the problems, a GIS platform is used as a support, and the communication quality of a planned meteor trail link is analyzed and predicted by combining specific elevation data, so that the method is completely realized by a program, and is efficient, reliable and convenient. The method fully considers the influence of the actual terrain environment on link opening, greatly improves the accuracy of site selection of the meteor trail station and link planning, and is particularly suitable for communication site selection and link planning prediction in the design stage of the meteor trail communication system in the complex terrain environment.
Description
Technical Field
the invention belongs to the technical field of communication, relates to a meteor trail link planning and predicting method based on a GIS (geographic Information system), and is particularly suitable for communication station address selection and link planning prediction in the design stage of a meteor trail communication system in a complex terrain environment.
Background
meteoric trail communication belongs to a long-distance burst communication mode, and reliable information transmission with a single-hop communication distance of 500-2000km can be realized within a frequency range of 30-50 MHz. As an important communication means of minimum emergency communication, meteor trail communication is widely applied to emergency communication safeguards such as strategic emergency communication systems in the national defense and military field and meteorological data acquisition, hydrological monitoring, disaster reporting and the like in the civil field.
The construction process of the meteor trail channel model is relatively complex, the occurrence of meteor phenomenon has strong regionality, and the communication quality of the meteor trail link is closely related to geographic information such as terrain, landform and the like, so that the estimation of the meteor trail link has high calculation difficulty. The traditional meteor trail link analysis method depends on manual prediction of operation on a graph, and can be finally determined only by field survey after a station address is selected to complete link budget, so that the problems of large workload, low prediction efficiency, poor result accuracy and the like exist.
Disclosure of Invention
the invention provides a meteor trail link planning and prediction method based on a GIS (geographic information system) system, aiming at overcoming the defects of poor accuracy, low calculation efficiency and the like of the traditional meteor trail link planning method and comprehensively considering the influence of the actual terrain environment on link opening. The method is based on a GIS platform, analyzes and predicts the communication quality of the planned meteor trail link by combining specific elevation data, has the advantages of high accuracy, high calculation efficiency, convenience in operation, good visualization effect and the like, and can provide reliable auxiliary decision support for the deployment and the opening of the meteor trail link.
the invention is realized by the following technical scheme:
A meteor trail link planning and predicting method based on a GIS (geographic information system) comprises the following steps:
(1) After the electronic map is loaded, selecting a transmitting end site and a receiving end site of the meteor trail link according to geographic information data provided by a GIS (geographic information system), allocating meteor trail communication equipment for the sites, and connecting icons of the two selected sites in a pair on the electronic map to complete link establishment;
(2) Calculating the great circle distance and meteor trail height between two stations by using a spherical geometric formula according to the geographical position information of the selected station and the working frequency parameter of meteor trail communication equipment;
(3) Acquiring elevation information of a transmitting end station and a receiving end station, respectively estimating the elevation angles of the antennas of the transmitting end station and the receiving end station by combining the calculated great circle distance and meteor trail height, judging whether a link meets communication requirements or not according to an elevation angle constraint range, and executing the step (4) if the link meets the communication requirements; otherwise, judging that the link is not accessible;
(4) respectively calculating the antenna frame heights of the transmitting end station and the receiving end station according to the estimated antenna elevation angles of the transmitting end station and the receiving end station and an actual engineering empirical formula, respectively comparing the antenna frame heights of the transmitting end station and the receiving end station with the antenna frame height range of meteor trail communication equipment equipped by the station, judging whether a link meets communication requirements, and if so, executing the step (5); otherwise, judging that the link is not accessible;
(5) according to the longitude and latitude information of the transmitting end station and the receiving end station, carrying out data sampling on the elevation value of the link profile, and calculating the meteor trail intersection point position according to the antenna elevation angle and the antenna frame height of the transmitting end station and the receiving end station; the elevation value of the link profile and the intersection point position of the meteor trail are used for drawing and displaying a link elevation profile, whether the link is shielded or not is judged, if shielding exists, shielding point position information is obtained, plotting is completed on the profile, and the link is judged to be not communicated; otherwise, executing the step (6);
(6) according to the elevation profile of the link, calculating the receiving power of the meteor trail link according to a calculation formula of meteor trail receiving signal power, and further predicting the on-off state of the link;
and finishing planning and prediction of the meteor trail link based on the GIS system.
Wherein, the step (1) specifically comprises the following steps:
(101) In a GIS system, selecting a designated electronic map file, opening an electronic map and loading geographic information data;
(102) Respectively selecting the positions of a sending end station and a receiving end station on an electronic map;
(103) Selecting meteor trail communication equipment from a meteor trail communication equipment library, and sequentially allocating meteor trail communication equipment to a sending end station and a receiving end station;
(104) and selecting icons of the sending terminal station and the receiving terminal station on the electronic map for connection to finish the preliminary planning of the meteor trail link.
Wherein, the step (5) comprises the following steps:
(501) according to the longitude and latitude information of the transmitting end station and the receiving end station, carrying out data sampling on the elevation value of the link profile on a GIS (geographic information system);
(502) Spherical surface transformation is carried out on each sampling value on the link profile by utilizing a spherical surface geometric formula;
(503) Calculating the intersection point position of meteor trail according to the antenna elevation angle and the antenna elevation;
(504) utilizing the positions of the intersection points of the meteor trail and each sampling value on the link profile after the spherical surface transformation to draw and display a link elevation profile, wherein the drawing and display comprises plotting on a graph of a ground plane, the sampling elevation values, the intersection points of the trail and a radio wave propagation path;
(505) Calculating whether a link has shielding conditions according to the geometrical relationship among the incident path, the reflection path, the antenna elevation angle and the intersection point position of the trail, if the link has shielding, acquiring the position information of the shielding points, completing plotting on a sectional view, and judging that the link is not accessible; otherwise, step (6) is executed.
Compared with the background technology, the invention has the advantages that:
1. according to the invention, the influence of geographic factors such as landform and landform is fully considered by relying on elevation data provided by a GIS system, so that the accuracy of site selection and link planning of meteor trail sites is greatly improved;
2. compared with the traditional prediction method for the operation on the manual graph, the link planning process is completely realized by a program, manual calculation is not needed, and the method is more efficient, reliable and convenient;
3. the link elevation profile visualization method can realize the visualization of the link elevation profile, so that the link analysis is more visual;
4. when the link communication quality is predicted, the invention can provide the rapid positioning of the link failure factors, so that the adjustment of the link planning parameters is more targeted and more reasonable.
Drawings
FIG. 1 is a flow chart of a software implementation of the present invention;
FIG. 2 is a flow chart of the present invention for establishing meteor trail links;
FIG. 3 is a schematic view of the geometry of the meteor trail link elevation profile of the present invention;
fig. 4 is a graph comparing the link communication quality prediction results of the present invention with actual experimental data.
Detailed Description
the invention is described in further detail below with reference to the figures and specific examples.
fig. 1 is a software implementation flowchart of the present invention, and a meteor trail link planning and predicting method based on a GIS system specifically includes the following steps:
(1) And after the electronic map is loaded, selecting a sending terminal station and a receiving terminal station of the meteor trail link according to geographic information data provided by the GIS, and allocating proper meteor trail communication equipment for the stations. And connecting the icon pairs of the two selected sites on the electronic map to complete the link establishment.
As shown in fig. 2, a specific process for establishing a meteor trail link includes the following steps:
(101) in a GIS system, a designated electronic map file is selected, a map is opened, geographic information data is loaded, and the map file loading is finished by taking a Chinese map as an example.
(102) the positions of a sending end station and a receiving end station are respectively selected on the electronic map, and the stations can be accurately positioned by inputting specific longitude and latitude information.
The position information of the station comprises longitude, latitude and altitude, wherein the input modes of the longitude and the latitude comprise three modes, namely a degree, a degree and a minute second format, and the numerical value of the altitude is automatically acquired and displayed according to the input longitude and latitude information. In the embodiment, the spring and the Shijiazhuang are respectively selected as a sending end station and a receiving end station.
(103) Selecting communication equipment with proper model from the existing meteor trail communication equipment library, and sequentially allocating meteor trail communication equipment to the sending end station and the receiving end station.
the meteor trail communication equipment library comprises equipment of various types, and the equipment station types are divided into four types, namely a fixed main station, a vehicle-mounted main station, a box-type main station and a portable slave station. The related parameters of the equipment are six items, namely the equipment model, the antenna frame height, the number of the antennas, the equipment station type, the transmitting power and the transmitting frequency. In this embodiment, in this step, a fixed master station type meteor trail device is provided for the fountain of the sending site, and a vehicle-mounted master station type device is provided for the stone house of the receiving site.
(104) And selecting icons of the sending terminal station and the receiving terminal station on the electronic map to perform connection operation, and finishing the preliminary planning of the meteor trail link.
(2) according to the geographic position information, the working frequency and other parameters of the stations, the spherical geometric formula is utilized to calculate and obtain geometric parameters such as great circle distance, meteor trail height and the like between the two stations.
The concrete formula is
h＝124-17lg f
Wherein h is the meteor trail height, and f is the operating frequency of the meteor trail communication device (here, the average value of the operating frequency of the transmitting end and the operating frequency of the receiving end is taken).
(3) And acquiring elevation information of the transmitting station and the receiving station, and respectively estimating the antenna elevation angles of the transmitting station and the receiving station by combining the calculated parameters such as great circle distance, trail height and the like. Judging whether the link meets the communication requirement or not according to the elevation angle constraint range, and if so, entering the step (4) to continue execution; otherwise, the link is determined to be unavailable. In the embodiment, the elevation angle of the antenna of the wine spring-stone house link is 5.2 degrees, and the communication requirement is met within the restriction range of the elevation angle.
(4) acquiring the antenna frame heights of the stations of the transmitting end and the receiving end according to the calculated antenna elevation angle and an actual engineering empirical formula, comparing the antenna frame heights with the antenna frame height range of equipment equipped in the stations, judging whether a link meets communication requirements or not, and if so, entering the step (5) to continue execution; otherwise, the link is determined to be unavailable.
the practical engineering empirical formula is
Where θ is the calculated antenna elevation angle, f is the operating frequency, and λ is the wavelength.
(5) after various geometrical parameters of the link are obtained, the elevation information of each sampling point is read from the GIS system by sampling the profile of the link, and calculation analysis and visual display of the elevation profile of the link are completed.
FIG. 3 is a schematic diagram of the geometry of a meteor trail link elevation profile. The specific implementation of the link elevation profile analysis comprises the following steps:
(501) According to the longitude and latitude information of the transmitting and receiving stations, carrying out data sampling on the elevation value of the link profile from the GIS;
(502) Performing spherical transformation on each sampling value on the section by using a spherical geometric formula;
(503) calculating the intersection point position of the trail according to the parameters of the antenna elevation angle, the antenna frame and the like;
(504) the method comprises the following steps of finishing drawing and displaying of a link elevation profile by combining an elevation data set of profile sampling points, wherein drawing and displaying of elements such as a ground plane, a sampling elevation value, a trail intersection point and a radio wave propagation path are plotted on the graph;
(505) and calculating whether the link has shielding conditions according to the geometrical relationship of the parameters such as the incident path, the reflection path, the antenna elevation angle, the trail intersection point position and the like. If the shielding exists, acquiring position information of the shielding point, completing plotting on the sectional diagram, and judging that the link is not accessible; otherwise, the step (6) is entered for continuing execution.
in this embodiment, the calculated trace intersection point is located at 95.496km high above the 658km distance from the transmission station, and no blocking occurs on the radio wave propagation path of the link.
(6) And calculating the received power parameter of the meteor trail link according to a calculation formula of meteor trail received signal power by combining the elevation profile of the link, and further predicting the on-off state of the link. The formula for calculating the power of the meteor trail receiving signal is
Wherein PR is the receiving power, PT is the transmitting power, RT and RR are the distances from meteor trail to the transmitting end and the receiving end respectively, q is the electron linear density, and f is the working frequency.
In the embodiment, the received signal power calculated by the link is higher than the receiving threshold of the equipment and the environmental background noise, and the communication requirement is met, so that the on-off state of the link is predicted to be open.
And after the six steps are executed, planning and predicting the meteor trail link based on the GIS can be completed.
The method of the invention is realized by software programming by using C # language, and after a plurality of tests and verifications, the planning and predicting functions of the method can be further proved by a data comparison graph shown in figure 4. As can be seen from the analysis of fig. 4, for the parameters of the antenna elevation, the antenna elevation angle, the link on-off result, and the like of the link 1 and the link 2, the values of the measured data in the engineering test and the calculated result of the method of the present invention are all substantially the same. In conclusion, the meteor trail link planning and prediction method based on the GIS has good practicability, and can provide efficient and reliable auxiliary decision support for meteor trail site deployment and site selection and link planning and opening.
Claims (3)
1. A meteor trail link planning and predicting method based on a GIS (geographic information system) is characterized by comprising the following steps of:
(1) After the electronic map is loaded, selecting a sending terminal station and a receiving terminal station of the meteor trail link according to geographic information data provided by a GIS system, allocating meteor trail communication equipment for the stations, and connecting icons of the two selected stations on the electronic map in a pair to complete link establishment;
(2) calculating the great circle distance and meteor trail height between two stations by using a spherical geometric formula according to the geographical position information of the selected station and the working frequency parameter of meteor trail communication equipment;
(3) acquiring elevation information of a transmitting end station and a receiving end station, respectively estimating the elevation angles of the antennas of the transmitting end station and the receiving end station by combining the calculated great circle distance and meteor trail height, judging whether a link meets communication requirements or not according to an elevation angle constraint range, and executing the step (4) if the link meets the communication requirements; otherwise, judging that the link is not accessible;
(4) Respectively calculating the antenna frame heights of the transmitting end station and the receiving end station according to the estimated antenna elevation angles of the transmitting end station and the receiving end station and an actual engineering empirical formula, respectively comparing the antenna frame heights of the transmitting end station and the receiving end station with the antenna frame height range of meteor trail communication equipment equipped by the station, judging whether a link meets communication requirements, and if so, executing the step (5); otherwise, judging that the link is not accessible;
(5) according to the longitude and latitude information of the transmitting end station and the receiving end station, carrying out data sampling on the elevation value of the link profile, and calculating the meteor trail intersection point position according to the antenna elevation angle and the antenna frame height of the transmitting end station and the receiving end station; the elevation value of the link profile and the intersection point position of the meteor trail are used for drawing and displaying a link elevation profile, whether the link is shielded or not is judged, if shielding exists, shielding point position information is obtained, plotting is completed on the profile, and the link is judged to be not communicated; otherwise, executing the step (6);
(6) according to the elevation profile of the link, calculating the receiving power of the meteor trail link according to a calculation formula of meteor trail receiving signal power, and further predicting the on-off state of the link;
and finishing planning and prediction of the meteor trail link based on the GIS system.
2. The meteor trail link planning and predicting method based on GIS according to claim 1, characterized in that: the step (1) specifically comprises the following steps:
(101) in a GIS system, selecting a designated electronic map file, opening an electronic map and loading geographic information data;
(102) respectively selecting the positions of a sending end station and a receiving end station on an electronic map;
(103) selecting meteor trail communication equipment from a meteor trail communication equipment library, and sequentially allocating meteor trail communication equipment to a sending end station and a receiving end station;
(104) And selecting icons of the sending terminal station and the receiving terminal station on the electronic map for connection to finish the preliminary planning of the meteor trail link.
3. the meteor trail link planning and predicting method based on GIS according to claim 1, characterized in that: the step (5) specifically comprises the following steps:
(501) According to the longitude and latitude information of the transmitting end station and the receiving end station, carrying out data sampling on the elevation value of the link profile on a GIS (geographic information system);
(502) spherical surface transformation is carried out on each sampling value on the link profile by utilizing a spherical surface geometric formula;
(503) Calculating the intersection point position of meteor trail according to the antenna elevation angle and the antenna elevation;
(504) utilizing the positions of the intersection points of the meteor trail and each sampling value on the link profile after the spherical surface transformation to draw and display a link elevation profile, wherein the drawing and display comprises plotting on a graph of a ground plane, the sampling elevation values, the intersection points of the trail and a radio wave propagation path;
(505) calculating whether a link has shielding conditions according to the geometrical relationship among the incident path, the reflection path, the antenna elevation angle and the intersection point position of the trail, if the link has shielding, acquiring the position information of the shielding points, completing plotting on a sectional view, and judging that the link is not accessible; otherwise, step (6) is executed.
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