CN112566140A - Circular obstacle oriented method and system for judging communication path between communication nodes - Google Patents
Circular obstacle oriented method and system for judging communication path between communication nodes Download PDFInfo
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Abstract
The invention belongs to the technical field of wireless communication, and discloses a method and a system for judging a communication path between communication nodes facing a circular barrier. The method is used for judging whether a circular barrier shields a communication path between communication nodes, and comprises the following steps: step 1: acquiring the coordinate of a communication node O, the coordinate of a communication node X, the diameter of a circular obstacle B and the coordinate of the circle center of the circular obstacle; step 2: establishing a circular obstacle shielding area model, wherein the circular obstacle shielding area model comprises a rectangular area and two semicircular areas; and step 3: judging whether the circle center of the circular obstacle is in the circular obstacle shielding area model or not according to the proposed distance judgment criterion, and if the circle center of the circular obstacle is in the circular obstacle shielding area model, a link OX between the communication node O and the communication node X is a non-visual path; otherwise, link OX is a through path. The method can be used for the coverage planning and optimization of the millimeter wave mobile communication network.
Description
Technical Field
The invention belongs to the technical field of wireless communication, and relates to a method and a system for judging a communication path between communication nodes facing a circular obstacle.
Background
The stochastic geometry is generated by combining the integral geometry and the point process, and the spatial stochastic process, such as the spatial point process, is mainly researched. With the deep application of the random geometric theory in the fields of space statistics, stereo metrology and the like, the theory development is increasingly perfect and strong, and the random position of a node in a network can be accurately modeled and the influence of interference in the network can be analyzed. At present, random geometry successfully provides a unified mathematical paradigm for modeling and analyzing a large-scale wireless communication network, and the method is a new method for modeling the communication network, can truly restore the randomness of node distribution, analyzes the coverage characteristics of the large-scale network, and has important significance for network modeling of 5G and the like needing large-scale deployment of wireless access nodes.
In millimeter wave wireless communication, millimeter wave communication is easily affected by environmental obstacles because of its characteristics such as short wavelength and strong directivity. The experimental results show that: the path loss of millimeter wave line-of-sight propagation and non-line-of-sight propagation is greatly different, so that reasonable modeling of the barrier shielding effect has important significance for researching millimeter wave communication and coverage performance. In this respect, the mainstream method in the world at present is to model the barrier shielding effect by using a random shape theory and build a mathematical framework to establish a random blocking model. In the past, when the occlusion situation between nodes is judged, an inplogyon function and a for loop built in Matlab are generally adopted, and the occlusion effect of each node is judged in a serial mode, so that the program complexity is high and the operation efficiency is low.
Disclosure of Invention
The invention aims to provide a method and a system for judging a visibility path between communication nodes facing a circular barrier, which are used for solving the problem that the circular barrier is quickly judged to block the visibility path between the communication nodes in a millimeter wave wireless communication network.
In order to realize the task, the invention adopts the following technical scheme:
a circular obstacle-oriented method for judging a visibility path between communication nodes is used for judging whether the circular obstacle shields the visibility path between the communication nodes, and comprises the following steps:
step 1: acquiring the coordinate of a communication node O, the coordinate of a communication node X, the diameter of a circular obstacle B and the coordinate of the circle center of the circular obstacle;
step 2: establishing a circular obstacle shielding area model according to the coordinate of a communication node O, the coordinate of a communication node X and the diameter of a circular obstacle, wherein the circular obstacle shielding area model comprises a rectangular area and two semicircular areas, the length of the rectangular area is the distance from the communication node O to the communication node X, the width of the rectangular area is equal to the diameter of the semicircular area, the diameter of the semicircular area is the diameter of the circular obstacle, the two semicircular areas are respectively positioned on two sides of the rectangular area, and the communication node O and the communication node X are respectively positioned at the centers of circles of the two semicircular areas;
and step 3: judging whether the circle center of the circular obstacle is in the circular obstacle sheltering area model or not, and if the circle center of the circular obstacle is in the circular obstacle sheltering area model, enabling a link OX between the communication node O and the communication node X to be a non-communication path; otherwise, link OX is a through path.
Further, the area of the model of the shielding area of the circular obstacle
Wherein, beta is the diameter of the circular obstacle B, and R is the distance from the communication node O to the communication node X;
if the circle center of the circular obstacle B is in the circular obstacle shielding area model, the circular obstacle B meets the requirement
Or satisfy
Wherein d1 is the distance from the center of the circular obstacle B to the communication node X, d2 is the distance from the center of the circular obstacle B to the communication node O,
the system for judging the communication path between the communication nodes facing the circular obstacle comprises an acquisition unit, a modeling unit and a judgment unit;
the acquisition unit is used for acquiring the coordinates of the communication node O, the coordinates of the communication node X, the diameter of the circular obstacle and the coordinates of the circle center of the circular obstacle;
the modeling unit is used for establishing a circular obstacle shielding area model according to the coordinate of a communication node O, the coordinate of a communication node X and the diameter of a circular obstacle, the circular obstacle shielding area model comprises a rectangular area and two semicircular areas, the length of the rectangular area is the distance from the communication node O to the communication node X, the width of the rectangular area is equal to the diameter of the semicircular area, the diameter of the semicircular area is the diameter of the circular obstacle, the two semicircular areas are respectively positioned on two sides of the rectangular area, and the communication node O and the communication node X are respectively positioned at the centers of circles of the two semicircular areas;
the judging unit is used for judging whether the circular obstacle is in the circular obstacle sheltering area model or not, and if the circular obstacle is in the circular obstacle sheltering area model, a link OX between the communication node O and the communication node X is a non-communication path; otherwise, link OX is a through path.
Further, the area of the model of the shielding area of the circular obstacle
Wherein, beta is the diameter of the circular obstacle B, and R is the distance from the communication node O to the communication node X;
if the circle center of the circular obstacle B is in the circular obstacle shielding area model, the circular obstacle B meets the requirement
Or satisfy
Wherein d1 is the distance from the center of the circular obstacle B to the communication node X, d2 is the distance from the center of the circular obstacle B to the communication node O,
compared with the prior art, the invention has the following technical characteristics:
(1) the method can be used for the coverage planning and optimization of the millimeter wave mobile communication network. By quickly judging the shielding effect of the millimeter wave beam forming link and utilizing the relay forwarding equipment pre-arranged on the barrier node, the shielded signal is picked up and forwarded, so that the advantages of rich millimeter wave frequency band resources and strong link directivity are fully exerted, the defects of large millimeter wave communication path loss and easiness in shielding are overcome, and the network coverage effect is improved.
(2) The invention can reduce the complexity of the algorithm, and the existing algorithm firstly needs to draw the shielding area in the figure 1, so that the process is more complex. And then calling an inplogyon function built in Matlab to judge whether the link between the transmitting and receiving communication nodes is a communication link. Numerical experiments show that the inplogyon function has low operation efficiency, and the method does not need to draw a shielding area and does not use the inplogyon function any more, so the computational complexity of the program is obviously reduced.
(3) The method can improve the operation efficiency of the algorithm, the Matlab-based inplogyon function algorithm cannot realize the parallel judgment of the shielding effect of a plurality of barrier nodes, the shielding effect of each barrier node can be respectively judged only by using for circulation, the program operation efficiency is low, and the operation time is long. The invention can equivalently realize the same effect of the inplogyon function through efficient distance judgment, and supports the parallel judgment of multiple obstacle nodes, thereby improving the running efficiency of the program. Simulation results show that: compared with the prior algorithm, the algorithm has the advantage that the operation time is at least reduced by 47%.
Drawings
FIG. 1 is a schematic view of an obstacle sheltered area according to the present invention;
FIG. 2 is a schematic diagram of an occlusion model optimization scheme of the present invention;
fig. 3 is a comparison of the time taken to determine whether an LOS link exists between a pair of transceiving nodes according to the present invention versus using a prior algorithm.
Detailed Description
The technical vocabulary appearing in the invention is explained first:
a through-looking path: the direct transmission path between the transmitting node and the receiving node is not blocked by obstacles, and the transmitting node and the receiving node can see through.
Non-visual path: the direct transmission path between the transmitting node and the receiving node is blocked by obstacles, and the transmitting node and the receiving node cannot see through.
Round obstacles: refers to an obstacle that is circular in cross-section.
The embodiment discloses a method for judging a circular obstacle-oriented communication node-to-communication node visibility path, which is used for judging whether the circular obstacle obstructs the communication node-to-communication node visibility path, and comprises the following steps:
step 1: acquiring the coordinate of a communication node O, the coordinate of a communication node X, the diameter of a circular obstacle B and the coordinate of the circle center of the circular obstacle;
step 2: establishing a circular obstacle shielding area model according to the coordinate of a communication node O, the coordinate of a communication node X and the diameter of a circular obstacle, wherein the circular obstacle shielding area model comprises a rectangular area and two semicircular areas, the length of the rectangular area is the distance from the communication node O to the communication node X, the width of the rectangular area is equal to the diameter of the semicircular area, the diameter of the semicircular area is the diameter of the circular obstacle, the two semicircular areas are respectively positioned on two sides of the rectangular area, and the communication node O and the communication node X are respectively positioned at the centers of circles of the two semicircular areas;
and step 3: judging whether the circle center of the circular obstacle is in the circular obstacle sheltering area model or not, and if the circle center of the circular obstacle is in the circular obstacle sheltering area model, enabling a link OX between the communication node O and the communication node X to be a non-communication path; otherwise, link OX is a through path.
Specifically, the area of the model of the shielding region of the circular obstacle
Wherein, beta is the diameter of the circular obstacle B, and R is the distance from the communication node O to the communication node X;
if the circle center of the circular obstacle B is in the circular obstacle shielding area model, the circular obstacle B meets the requirement
Or satisfy
Wherein d1 is the distance from the center of the circular obstacle B to the communication node X, d2 is the distance from the center of the circular obstacle B to the communication node O,
in the invention, if the communication path exists, the node O and the node X can carry out communication direct transmission communication, and the transmission loss of a link is small; if the communication path does not exist, the node O and the node X can not directly communicate, and then relay forwarding communication can be carried out by means of the relay transceiver arranged on the obstacle node B.
The embodiment also discloses a circular obstacle-oriented system for judging the communication path between the communication nodes, which comprises an acquisition unit, a modeling unit and a judgment unit;
the acquisition unit is used for acquiring the coordinates of the communication node O, the coordinates of the communication node X, the diameter of the circular obstacle and the coordinates of the circle center of the circular obstacle;
the modeling unit is used for establishing a circular obstacle shielding area model according to the coordinate of a communication node O, the coordinate of a communication node X and the diameter of a circular obstacle, the circular obstacle shielding area model comprises a rectangular area and two semicircular areas, the length of the rectangular area is the distance from the communication node O to the communication node X, the width of the rectangular area is equal to the diameter of the semicircular area, the diameter of the semicircular area is the diameter of the circular obstacle, the two semicircular areas are respectively positioned on two sides of the rectangular area, and the communication node O and the communication node X are respectively positioned at the centers of circles of the two semicircular areas;
the judging unit is used for judging whether the circular obstacle is in the circular obstacle sheltering area model or not, and if the circular obstacle is in the circular obstacle sheltering area model, a link OX between the communication node O and the communication node X is a non-communication path; otherwise, link OX is a through path.
Specifically, the area of the model of the shielding region of the circular obstacle
Wherein, beta is the diameter of the circular obstacle B, and R is the distance from the communication node O to the communication node X;
if the circle center of the circular obstacle B is in the circular obstacle shielding area model, the circular obstacle B meets the requirement
Or satisfy
Wherein d1 is the distance from the center of the circular obstacle B to the communication node X, d2 is the distance from the center of the circular obstacle B to the communication node O,
specifically, the central point set of the nodes of the circular obstacle obeys poisson point distribution, and the density is lambda.
Specifically, the transmitting node O and the receiving node X need to be equipped with millimeter wave transmitting and receiving equipment, and the blocking node B needs to be equipped with millimeter wave transceiver equipment, and the millimeter wave transceiver equipment has the capability of detecting the incoming wave direction, and can determine the transmitting beam direction of relay forwarding according to the incoming wave direction.
Example 1
The embodiment discloses an experimental environment as follows: considering that the distance between the millimeter wave transceiving communication nodes is 20m, the nodes of the circular obstacles are randomly and uniformly distributed among the transceiving nodes, and the density variation range of the randomly distributed nodes of the circular obstacles is 10-6～10-3Number per square meter, number of simulations: 103 times. The experimental results show that: the simulation time is reduced by at least about 47%.
Under the condition, whether a circular obstacle node exists on a communication path between the transmitting and receiving nodes can be efficiently calculated by adopting the method provided by the patent. If the circular obstacle node does not exist, the communication path communication can be realized through the millimeter wave beam of the transmitting node pointing to the receiving node. If the circular obstacle node exists, the millimeter wave transceiver equipment deployed on the obstacle node can be used for relaying and forwarding the blocked signal.
As shown in fig. 1, when the center of the circular obstacle node (i.e., point B in fig. 2) is within the area shown in fig. 1, an occlusion will occur for the OX link. Fig. 3 shows the time required for judging whether a visibility path exists in the method for judging a visibility path and the conventional algorithm.
Claims (4)
1. A circular obstacle-oriented method for judging a visibility path between communication nodes is characterized by being used for judging whether the circular obstacle shields the visibility path between the communication nodes, and comprising the following steps of:
step 1: acquiring the coordinate of a communication node O, the coordinate of a communication node X, the diameter of a circular obstacle B and the coordinate of the circle center of the circular obstacle;
step 2: establishing a circular obstacle shielding area model according to the coordinate of a communication node O, the coordinate of a communication node X and the diameter of a circular obstacle, wherein the circular obstacle shielding area model comprises a rectangular area and two semicircular areas, the length of the rectangular area is the distance from the communication node O to the communication node X, the width of the rectangular area is equal to the diameter of the semicircular area, the diameter of the semicircular area is the diameter of the circular obstacle, the two semicircular areas are respectively positioned on two sides of the rectangular area, and the communication node O and the communication node X are respectively positioned at the centers of circles of the two semicircular areas;
and step 3: judging whether the circle center of the circular obstacle is in the circular obstacle sheltering area model or not, and if the circle center of the circular obstacle is in the circular obstacle sheltering area model, enabling a link OX between the communication node O and the communication node X to be a non-communication path; otherwise, link OX is a through path.
2. The method for judging visibility path between communication nodes facing circular obstacle according to claim 1, wherein the area of the model of the area covered by the circular obstacle
Wherein, beta is the diameter of the circular obstacle B, and R is the distance from the communication node O to the communication node X;
if the circle center of the circular obstacle B is in the circular obstacle shielding area model, the circular obstacle B meets the requirement
Or satisfy
Wherein d1 is the distance from the center of the circular obstacle B to the communication node X, d2 is the distance from the center of the circular obstacle B to the communication node O,
3. the round obstacle oriented system for judging the communication path between communication nodes is characterized by comprising an acquisition unit, a modeling unit and a judgment unit;
the acquisition unit is used for acquiring the coordinates of the communication node O, the coordinates of the communication node X, the diameter of the circular obstacle and the coordinates of the circle center of the circular obstacle;
the modeling unit is used for establishing a circular obstacle shielding area model according to the coordinate of a communication node O, the coordinate of a communication node X and the diameter of a circular obstacle, the circular obstacle shielding area model comprises a rectangular area and two semicircular areas, the length of the rectangular area is the distance from the communication node O to the communication node X, the width of the rectangular area is equal to the diameter of the semicircular area, the diameter of the semicircular area is the diameter of the circular obstacle, the two semicircular areas are respectively positioned on two sides of the rectangular area, and the communication node O and the communication node X are respectively positioned at the centers of circles of the two semicircular areas;
the judging unit is used for judging whether the circular obstacle is in the circular obstacle sheltering area model or not, and if the circular obstacle is in the circular obstacle sheltering area model, a link OX between the communication node O and the communication node X is a non-communication path; otherwise, link OX is a through path.
4. The circular-obstacle-oriented system for judging visibility between communication nodes as claimed in claim 3, wherein the area of the model of the circular-obstacle-covered region is larger than the area of the model of the circular-obstacle-covered region
Wherein, beta is the diameter of the circular obstacle B, and R is the distance from the communication node O to the communication node X;
if the circle center of the circular obstacle B is in the circular obstacle shielding area model, the circular obstacle B meets the requirement
Or satisfy
Wherein d1 is the distance from the center of the circular obstacle B to the communication node X, d2 is the distance from the center of the circular obstacle B to the communication node O,
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