A dynamic blocking characteristic analysis method, system and terminal

Abstract

The application belongs to the technical field of millimeter wave communication, and discloses a dynamic blocking characteristic analysis method, system and terminal, which solves the deficiency of the existing relay-assisted millimeter wave system in blocking characteristic analysis and solves the problem of uplink and downlink correlation of the relay. The relay-assisted millimeter wave communication system is set, and the movement and density of the dynamic obstacle and the density and position of the relay are randomly modeled. The conditional probability of a single relay link being blocked is calculated by using the uplink and downlink correlation of the relay. The conditional probability of multiple relay links being blocked is calculated by using the independence between different relay links. The closed form of the probability of multiple relay links being blocked is obtained by integration, Taylor expansion, etc., and the blocking probability under the condition that the user exists self-blocking is analyzed based on the closed form. The application can provide a theoretical basis for deploying relays or reflecting surfaces in the millimeter wave system, make the deployment position and density more reasonable, effectively improve the service quality of the communication system, and reduce the operation cost of the system.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of millimeter wave communication, and particularly relates to a dynamic blocking characteristic analysis method and system and a terminal. BACKGROUND

[0002] Currently, millimeter wave communication systems have been facing two big problems in practical application: first, millimeter wave bands suffer higher path loss than low frequency bands, which makes the communication distance of millimeter wave shorter; second, millimeter wave has poor diffraction and bending ability, resulting in high sensitivity of millimeter wave to link blocking, especially dynamic blocking has a great influence on millimeter wave channel gain. One of the possible solutions to improve the poor propagation characteristics of millimeter wave signals is beamforming technology, which can compensate for the huge path loss of millimeter wave to some extent and improve the performance of the system, but it cannot effectively overcome the blocking effect of millimeter wave signals. The second possible solution to solve the above problems is to use relay to assist millimeter wave communication, which can extend the communication distance of signals on the one hand, and use relay link to provide services in the case of user line-of-sight link being blocked on the other hand, which helps to solve the signal blocking problem and improve the reliability of signal transmission. Therefore, it has strong practical significance to analyze the blocking effect in relay-assisted millimeter wave systems.

[0003] Random geometry theory is a common obstacle modeling method. M. Gapeyenko, A. Samuylov, and M. Gerasimenko in the paper "On the Temporal Effects of Mobile Blockers in Urban Millimeter-Wave Cellular Scenarios" and V. Petrov, D. Solomitckii, and A. Samuylov et al. in the paper "Dynamic Multi-Connectivity Performance in Ultra-Dense Urban mmWave Deployments" use random geometry method to study the static blocking caused by permanent structures such as buildings; at the same time, M. Gapeyenko, A. Samuylov, and M. Gerasimenko also analyze the influence of static human body on millimeter wave link in their paper "Analysis of Human-Body Blockage in Urban Millimeter-Wave Cellular Communications", which initiatively calculates the average length of line-of-sight and non-line-of-sight areas. Although analyzing static blocking is important for building millimeter wave communication systems. But in open scenarios (such as open parks, urban traffic scenarios), dynamic obstacles have a more significant influence on millimeter wave links.

[0004] To study the blocking characteristics of dynamic obstacles, Fahd Nasser Alsaleem, John S. Thompson, and David I. Laurenson in the paper "Adaptive Sum of Markov Chains for Modelling 3D Blockage in mmWave V2I Communications" simulated the blocking effect of pedestrians on the communication link between base stations and cars in urban traffic scenarios using the Knife-Edge Diffraction blocking model (KED) of the 3GPP protocol. In the paper "Analysis of Blockage Effects on Roadside Relay-assisted mmWave Backhaul Networks", Yuchen Liu and Douglas M. Blough analyzed the blocking of vehicles to the link between relays under the assumption that the positions of base stations and relays are fixed, and considered the impact of obstacles located in the blocking overlap area on the blocking probability. Through simulation, they explored the optimal positions of relays and base stations. The dynamic obstacles considered in the above scenarios, such as cars and pedestrians, can only move in a specific direction (road direction) and cannot well depict more open scenarios.

[0005] To this end, Mikhail Gerasimenko, Dmitri Moltchanov, and Margarita Gapeyenko in the paper "Capacity of Multiconnectivity mm Wave Systems With Dynamic Blockage and Directional Antennas" studied the impact of various parameters such as the density and height of mmWave access points, multi-connectivity strategies, the density and speed of obstacles, and the number of elements in the antenna array on the communication capacity. However, they only have theoretical results and do not compare simulation results. I.K. Jain, R. Kumar, and S.S. Panwar in the papers "The Impact of Mobile Blockers on Millimeter Wave Cellular Systems" and "Driven by Capacity or Blockage? A Millimeter Wave Blockage Analysis" proposed an analysis model that combines the effects of static blocking, dynamic blocking, and self-blocking. However, they did not consider the correlation of links in the multi-connection case and the impact of the introduction of relays on the blocking characteristics of the system.

[0006] Through the above analysis, the problems and defects of the prior art are that: the existing research on dynamic blocking in the millimeter wave communication system under the assistance of relay is quite limited, mostly only considering the single link from the transmitter to the receiver, or specifying the movement in a certain direction to simulate the dynamic blocking, which has certain limitations. Therefore, how to more reasonably construct a dynamic blocking model, and consider the correlation between the uplink and downlink communication links of the relay, to obtain more accurate blocking characteristics, is one of the hotspots in the current millimeter wave communication research, and is also the problem to be solved by the present application. SUMMARY

[0007] In view of the problems existing in the prior art, the present application provides a dynamic blocking characteristic analysis method, system and terminal.

[0008] The present application is implemented in the following manner: a dynamic blocking characteristic analysis method sets a relay-assisted millimeter wave communication system, first, the movement and density of the dynamic obstacles and the density and position of the relay are randomly modeled; then, the conditional probability of a single relay link being blocked is calculated using the correlation between the uplink and downlink links of the relay; the conditional probability of multiple relay links being blocked is calculated using the independence between different relay links; finally, the closed form of the probability of multiple relay links being blocked is obtained through integration and Taylor expansion, and the blocking probability under the condition that the user exists self-blocking is analyzed.

[0009] Further, the dynamic blocking characteristic analysis method specifically includes the following steps:

[0010] Step one, a millimeter wave transmitter T X with a height of h T , a millimeter wave receiver R X with a height of h D , and a distance between T X and R X of 2d, the midpoint of the line connecting the two is point O, point O is the origin of the coordinate axis, and a square open area with a side length of 2L (L> d) is set as the target scene with point O as the center, and the relay and potential dynamic obstacles are randomly distributed in the entire square area to form a communication system;

[0011] Step two, the distribution of the dynamic obstacles is set to follow a Poisson point process with a density of λ B , each obstacle moves at a speed V, the angle between the moving direction and the x-axis is ψ, which is uniformly distributed on [0, 2π], and the height of the obstacle is h B ; the distribution of the relay is set to follow a Poisson point process with a density of λ R , when the number of relays M is given, the two-dimensional position coordinates (x i , y i ) of the i-th relay R i (i = 1, 2, …, M) are determined.) follows a uniform distribution, where x is the x-axis coordinate. i and y-axis coordinates i All follow a uniform distribution on the interval [-L, L], and the relay height is set to h. R ;

[0012] Step 3, transmitter T X To relay R i Communication link T X →R i and relay R i To receiver R X Communication link R i →R X Both have an "effective blocking zone." When an obstacle is located within the "effective blocking zone," the communication link will be blocked. This occurs when h is satisfied. R >h B >h T =h D At that time, for T X →R i Relay uplink, T X →R i The length of the effective blocking area of ​​the link is in, For relay R i To T X The distance, the obstacle reaches T X →R i Blocking rate of the effective blocking area of ​​the link Block the obstacle T X →R i The blocking process of the link is modeled as a blocking rate of An alternating update process with an unblocked rate of μ is set up with an event. Indicates link T X →R i If blocked, then given the number of relays m and the number of relays R... i Under the condition of two-dimensional position coordinates, the event The conditional probability of occurrence is For R i →R X Relay downlink, R i →R X Length of the effective blocking area of ​​the link in For relay R i To R X The distance to the obstacle, reaching R i →R X Blocking rate of the effective blocking area of ​​the link Block the obstacle R i →RX The blocking process of the link is modeled as a blocking rate of The alternating update process with an unblocked rate of μ, the event Indicates link R i →R X If blocked, then given the number of relays M and the number of relays R... i Under the condition of two-dimensional position coordinates, the event The conditional probability of occurrence is

[0013] Step 4, Event B i Indicates transmitter T X via relay R i Forward to R X The entire communication link T X →R i →R X If blocked, then the event Among them, the event Representative link T X →R i Unobstructed, and the event Complementary; event Representative link R i →R X Unobstructed, and the event Complementary; ∩ represents the intersection of two events; then, given the number of relays M and the number of relays R... i Given two-dimensional position coordinates, for event B i The conditional probability of occurrence P(B) i |M,x i ,y i Perform calculations;

[0014] Step 5: Based on the conditional probability of a single relay link being completely blocked, known from Step 4, event B represents all available relay forwarding links T within the target scenario. X →R i →R X If i = 1, 2, ..., M, all are blocked, calculate the probability P(B) of event B occurring;

[0015] Step 6: In the target scenario, the user creates a self-blocking area with an angle of ω (0≤ω≤π / 2) due to the obstruction of their own body. Define event D as at least one relay being located outside the self-blocking area. Given event D, calculate the conditional probability P(B|D) of all relay forwarding links being blocked.

[0016] Furthermore, the fourth event B in step four i The conditional probability of occurrence is:

[0017]

[0018] Furthermore, the probability P(B) in step five is calculated as follows:

[0019] (5a) Calculate the probability P(B|M,x) i ,y i (i = 1, ..., M), which represents the number of relays M that can provide service, and the coordinates (x, y) of the relays. i ,y i The conditional probability of a relay link being blocked when i = 1, ..., M can be expressed as the product of the conditional probabilities of a single relay link being blocked:

[0020]

[0021] (5b) For P(B|M,x) in step (5a) i ,y i (i = 1, ..., M) with respect to x i Integrating the distribution yields P(B|M,y) i The expression (i = 1, ..., M) is:

[0022]

[0023] Wherein, P(B|M,y) i (i = 1, ..., M) represents the expression for a given number of relays M and the y-coordinates of all relays. i The conditional blocking probability when (i = 1, ..., M);

[0024] (5c) In step (5b), P(B|M,y) i y in (i = 1, ..., M) i (i=1,…,M) also follows a uniform distribution in [-L,L], and its probability density function is By analyzing P(B|M,y) i (i = 1, ..., M) with respect to the variable y i Find the expected value of the distribution of i = 1, ..., M:

[0025]

[0026] in

[0027] P(B|M) represents the conditional probability that all relay forwarding links are blocked when the number of relays M is given and the relay locations are arbitrary.

[0028] (5d) For f(x) in step (5c) i ,y iWe obtain the following through Taylor approximation:

[0029]

[0030] Where φ=2λ B Vρ, f(x) i ,y i The Taylor approximation of ) can be divided into two parts, and by integrating each part, we get:

[0031]

[0032]

[0033] in,

[0034]

[0035]

[0036]

[0037] arctan is the arctangent function. The symbol "defined as" represents the meaning of the symbol.

[0038] (5e) f(x) obtained in (5d) i ,y i Substituting the integral result into the expression obtained in (5c), we get:

[0039]

[0040] in It's about λ B A function of V and ρ Where arctanh() is the inverse hyperbolic tangent function;

[0041] (5f) By taking the mean of the distribution of variable M, the probability expression for event B is obtained as follows:

[0042]

[0043] in Let M be the probability density function of variable M. A S =4L 2 This represents the area of ​​the square target scene.

[0044] Furthermore, the conditional probability P(B|D) in step six is ​​calculated as follows: the area of ​​the self-blocking region is:

[0045]

[0046] in, Let represent the angle between the line connecting the user and the vertex of the square scene that is blocked by the user, and the x-axis. tan() is the tangent function, and cot() is the cotangent function. Only relays located outside this region can provide the auxiliary communication services mentioned above. Therefore, the probability that N relays are located outside the self-blocking region is... Event D represents the probability that at least one relay is located outside the self-blocking area. Given event D, the conditional probability that the relay link is blocked is:

[0047] Another object of the present invention is to provide a computer device including a memory and a processor, the memory storing a computer program, which, when executed by the processor, causes the processor to perform the steps of the dynamic blocking characteristic analysis method.

[0048] Another object of the present invention is to provide a computer-readable storage medium storing a computer program, which, when executed by a processor, causes the processor to perform the steps of the dynamic blocking characteristic analysis method.

[0049] Another object of the present invention is to provide an information data processing terminal, which is used to implement the steps of the dynamic blocking characteristic analysis method.

[0050] Another object of the present invention is to provide a dynamic blocking characteristic analysis system for implementing the aforementioned dynamic blocking characteristic analysis method, the dynamic blocking characteristic analysis system comprising:

[0051] The randomization modeling module is used to randomize the movement and density of dynamic obstacles, as well as the density and location of relays.

[0052] The conditional probability calculation module is used to calculate the conditional probability of a single relay link being blocked by utilizing the correlation between the uplink and downlink of the relay; and then to calculate the conditional probability of multiple relay links being blocked by utilizing the independence between different relay links.

[0053] The blocking probability analysis module is used to obtain the closed-form probabilities of multiple relay links being blocked through integration and Taylor expansion, and to analyze the blocking probability when users self-block.

[0054] Another objective of the present invention is to provide a millimeter-wave communication terminal, wherein the millimeter-wave communication terminal is equipped with the aforementioned dynamic blocking characteristic analysis system.

[0055] Based on the above technical solutions and the technical problems solved, please analyze the advantages and positive effects of the technical solution to be protected by this invention from the following aspects:

[0056] First, addressing the technical problems and difficulties in solving the aforementioned existing technologies, and closely combining the technical solution to be protected by this invention with the results and data from the research and development process, this paper provides a detailed and in-depth analysis of how the technical solution of this invention solves the technical problems and the creative technical effects brought about after solving the problems. Specifically, when the direct link between the receiver and transmitter is blocked, the probability of all serviceable relays being blocked can be accurately calculated. This provides a theoretical basis for deploying relays or intelligent reflectors in future millimeter-wave communication systems, helps solve the dynamic blocking effect of millimeter waves, thereby improving the reliability of signal transmission and enhancing system performance.

[0057] Secondly, considering the technical solution as a whole or from a product perspective, the technical effects and advantages of the technical solution protected by this invention are specifically described as follows: Addressing the high propagation loss and high sensitivity to obstacles in non-line-of-sight millimeter-wave communication links, utilizing relay-assisted millimeter-wave communication is an effective way to solve these problems. When facing dynamic obstacles, a method for analyzing the dynamic obstruction probability of a relay-assisted millimeter-wave communication system is designed. This method can accurately assess the dynamic obstruction characteristics of the entire system, predict the obstruction of direct line-of-sight links and relay links between targets, thereby providing data support for deploying relays or intelligent reflectors in different scenarios. This allows for more scientific and reasonable deployment locations and densities, effectively improving the service quality of the communication system while reducing its operating costs.

[0058] This invention studies the dynamic obstruction characteristics of millimeter-wave communication systems with relay assistance and proposes a method for calculating the dynamic obstruction probability of multiple relay links. On one hand, it considers the randomness of the moving direction of dynamic obstructors, making it more representative than existing dynamic obstruction analyses in urban traffic scenarios. On the other hand, considering the correlation between relay uplink and downlink, it analyzes both the dynamic obstruction effect of a single relay link and the dynamic obstruction characteristics when multiple connections exist in the case of multiple relays. Compared with general static cases or obstruction analyses that do not consider the correlation between relay uplink and downlink, this method considers more comprehensive factors and is more in line with practical applications, thus effectively overcoming the high sensitivity of millimeter-wave signals to obstruction and improving the reliability of signal transmission. The method proposed in this invention can not only provide a theoretical basis for the relay deployment of millimeter-wave communication systems but also provide a theoretical foundation for the future deployment of intelligent reflectors, UAV base stations, etc.

[0059] Third, as supplementary evidence of the inventive step of the claims of this invention, it is also reflected in the following important aspects:

[0060] (1) The expected benefits and commercial value of the technical solution of this invention after transformation are as follows:

[0061] This invention can be applied to application scenarios of deploying millimeter-wave communication in next-generation mobile communication systems, such as live sports events with high throughput requirements and urban hotspot service scenarios. Therefore, it will play an important role in various popular cultural and sports activities, such as the Olympic Games, the National Games, marathons, and concerts, and has great commercial application value.

[0062] (2) The technical solution of this invention fills a technical gap in the industry both domestically and internationally:

[0063] Existing technologies, both domestically and internationally, lack accurate analysis and modeling of the dynamic blocking characteristics of relay-assisted millimeter-wave communication systems, resulting in system performance analysis that is detached from reality and cannot be applied or implemented in practice. This invention establishes an accurate dynamic blocking characteristic analysis model for relay-assisted millimeter-wave communication systems using stochastic geometry theory, and in particular, provides a simple method for calculating the dynamic blocking probability of the link. This provides an effective analytical tool for the practical deployment and application of millimeter-wave communication technology, filling a technological gap in this field.

[0064] (3) Whether the technical solution of the present invention solves the technical problem that people have long wanted to solve but have never been able to solve successfully:

[0065] Relay-assisted millimeter-wave communication technology is one of the key technologies in fifth-generation and next-generation communication systems. However, millimeter-wave signals are easily blocked by obstacles, especially dynamic obstruction caused by moving people and vehicles, which severely affects system performance and hinders its widespread application in practice. Therefore, how to analyze and model the dynamic obstruction characteristics of relay-assisted millimeter-wave communication systems has been a long-standing but unresolved problem in the industry. In particular, the correlation between the uplink and downlink of the relay makes link obstruction characteristic analysis difficult to solve, and existing theories have not solved this problem. This invention, through multiple reasonable approximations and simplifications, finally derives an accurate dynamic obstruction characteristic analysis model for relay-assisted millimeter-wave communication systems, as well as a simple method for calculating the dynamic obstruction probability, effectively solving this problem. Attached Figure Description

[0066] Figure 1 This is a flowchart of the dynamic blocking characteristic analysis method provided in the embodiments of the present invention;

[0067] Figure 2 This is a schematic diagram of the dynamic blocking characteristic analysis system provided in an embodiment of the present invention;

[0068] Figure 3 This is a flowchart of the dynamic blocking characteristic analysis method provided in the embodiments of the present invention;

[0069] Figure 4 This is a system model diagram provided in an embodiment of the present invention;

[0070] Figure 5 This is a schematic diagram of the user self-blocking area provided in an embodiment of the present invention;

[0071] Figure 6 The relay height h provided in the embodiments of the present invention R =3m, when the speed of the blocker is V = 1m / s, and the density of the blocker is λ B The self-blocking angle ω is 0.1 and 0.5bl / m, respectively. 2 When the conditional blocking probability P(B|D) and relay density λ are 0 and π / 3 respectively, the method of this invention yields the following results: R A comparative curve chart showing the relationship between them;

[0072] Figure 7 The relay height h provided in the embodiments of the present invention R =3m, when the speed of the blocker is V = 1m / s, and the density of the blocker is λ B The self-blocking angle ω is 0.1 and 0.5bl / m, respectively. 2 When the conditions are 0 and π / 3, the conditional blocking probability P(B|D) and the density λ of the dynamic obstacle obtained by the method of this invention are... B A comparative curve chart showing the relationship between them;

[0073] Figure 8 The relay density λ provided in the embodiments of the present invention R =100 / km 2 When the speed of the obstructor is V = 1 m / s and the density of the obstructor is λ B The self-blocking angle ω is 0.1 and 0.5bl / m, respectively. 2 When the conditions are 0 and π / 3, the conditional blocking probability P(B|D) and relay height h obtained by the method of this invention are... R A comparative curve chart showing the relationship between them;

[0074] Figure 9 The relay density λ provided in the embodiments of the present invention R =100 / km 2 relay height h R =3m, and the density of the blockers is λ B The self-blocking angle ω is 0.1 and 0.5bl / m, respectively. 2 A comparison curve of the relationship between the conditional blocking probability P(B|D) and the velocity V of the dynamic obstacle obtained by the method of the present invention at 0 and π / 3.

[0075] In the diagram: 1. Randomization modeling module; 2. Conditional probability calculation module; 3. Blocking probability analysis module. Detailed Implementation

[0076] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0077] I. Explanatory and Illustrative Embodiments. To enable those skilled in the art to fully understand how the present invention is specifically implemented, this section provides an explanatory and illustrative description of the embodiments described in the claims.

[0078] like Figure 1 As shown, the dynamic blocking characteristic analysis method provided in this embodiment of the invention includes:

[0079] S101: First, randomize the movement and density of dynamic obstacles and the density and location of relays;

[0080] S102: Then, the conditional probability of a single relay link being blocked is calculated using the correlation between the uplink and downlink of the relay; then, the conditional probability of multiple relay links being blocked is calculated using the independence between different relay links.

[0081] S103: Finally, the probability closed loop of multiple relay links being blocked is obtained through integration, Taylor expansion, etc., and the blocking probability is analyzed based on this.

[0082] like Figure 2 As shown, the dynamic blocking characteristic analysis system provided in this embodiment of the invention includes:

[0083] Randomization modeling module 1 is used to randomize the movement and density of dynamic obstacles and the density and location of relays.

[0084] Conditional probability calculation module 2 is used to calculate the conditional probability of a single relay link being blocked by utilizing the correlation between the uplink and downlink of the relay; and then to calculate the conditional probability of multiple relay links being blocked by utilizing the independence between different relay links.

[0085] Blocking probability analysis module 3 is used to obtain the closed-form probabilities of multiple relay links being blocked through integration, Taylor expansion, etc., and based on this, analyzes the blocking probability in the case of user self-blocking.

[0086] The technical solution of the present invention will be further described below with reference to the accompanying drawings.

[0087] like Figure 3As shown, the dynamic obstruction probability analysis method for relay-assisted millimeter-wave communication systems proposed in this invention includes the following steps:

[0088] Step 1. As Figure 4 As shown, let the millimeter-wave transmitter T... X Height is h T Millimeter wave receiver R X Height is h D T X With R X The distance between them is 2d, and the midpoint of the line connecting them is denoted as point O. Point O is set as the origin of the coordinate axis. A square open area with a side length of 2L (L>d) is set as the target scene with point O as the center. Relays and potential dynamic obstacles are randomly distributed throughout the square area to form a communication system.

[0089] Step 2. The distribution of dynamic obstacles is set according to a density of λ. B The process is a Poisson point process, where each obstacle moves with a velocity V, and the angle ψ between the direction of movement and the x-axis follows a uniform distribution on [0, 2π]. The height of the obstacle is set as h. B The relay distribution is set according to a density of λ. R The Poisson point process, given the number of relays M, the i-th relay R i Two-dimensional position coordinates (x) of (i = 1, 2, ..., M) i ,y i ) follows a uniform distribution, that is, the x-axis coordinate x i and y-axis coordinates i All follow a uniform distribution on the interval [-L, L], and the relay height is set to h. R .

[0090] Step 3. Transmitter T X To relay R i Communication link T X →R i and relay R i To receiver R X Communication link R i →R X Both have an "effective blocking zone." When an obstacle is located within the "effective blocking zone," the communication link will be blocked. This occurs when h is satisfied. R >h B >h T =h D At that time, for T X →R i Relay uplink, T X →R i The length of the effective blocking area of ​​the link is in, For relay Ri To T X The distance, the obstacle reaches T X →R i Blocking rate of the effective blocking area of ​​the link Block the obstacle T X →R i The blocking process of the link is modeled as a blocking rate of An alternating update process with an unblocked rate of μ is set up with an event. Indicates link T X →R i If blocked, then given the number of relays m and the number of relays R... i Under the condition of two-dimensional position coordinates, the event The conditional probability of occurrence is For R i →R X Relay downlink, R i →R X Length of the effective blocking area of ​​the link in For relay R i To R X The distance to the obstacle, reaching R i →R X Blocking rate of the effective blocking area of ​​the link Block the obstacle R i →R X The blocking process of the link is modeled as a blocking rate of An alternating update process with an unblocked rate of μ is set up with an event. Indicates link R i →R X If blocked, then given the number of relays M and the number of relays R... i Under the condition of two-dimensional position coordinates, the event The conditional probability of occurrence is

[0091] Step 4. Set Event B i Indicates transmitter T X via relay R i Forward to R X The entire communication link T X →R i →R X If blocked, then the event Among them, the event Representative link T X →R i Unobstructed, and the event Complementary; event Representative link R i →R XUnobstructed, and the event Complementary; ∩ represents the intersection of two events; then, given the number of relays M and the number of relays R... i Given two-dimensional position coordinates, event B i The conditional probability of occurrence is:

[0092]

[0093] Step 5. Based on Step 4, the present invention already knows the conditional probability of a single relay link being completely blocked. Assume event B represents all available relay forwarding links T within the target scenario. X →R i →R X If i = 1, 2, ..., M, all are blocked, the probability P(B) is calculated as follows:

[0094] (5a) Calculate the probability P(B|M,x) i ,y i (i = 1, ..., M), which represents the number of relays M that can provide service, and the coordinates (x, y) of the relays. i ,y i The conditional probability of a relay link being blocked when i = 1, ..., M can be expressed as the product of the conditional probabilities of a single relay link being blocked, i.e.:

[0095]

[0096] (5b) For P(B|M,x) in step (5a) i ,y i (i = 1, ..., M) with respect to x i Integrating the distribution yields P(B|M,y) i The expression (i = 1, ..., M) is:

[0097]

[0098] Wherein, P(B|M,y) i (i = 1, ..., M) represents the expression for a given number of relays M and the y-coordinates of all relays. i The conditional blocking probability when (i = 1, ..., M);

[0099] (5c) In step (5b), P(B|M,y) i y in (i = 1, ..., M) i (i=1,…,M) also follows a uniform distribution in [-L,L], and its probability density function is By analyzing P(B|M,y) i (i = 1, ..., M) with respect to the variable y iFind the expected value of the distribution of i = 1, ..., M:

[0100]

[0101] in

[0102] P(B|M) represents the conditional probability that all relay forwarding links are blocked when the number of relays M is given and the relay locations are arbitrary.

[0103] (5d) For f(x) in step (5c) i ,y i We obtain the following through Taylor approximation:

[0104]

[0105] Where φ=2λ B Vρ, f(x) i ,y i The Taylor approximation of ) can be divided into two parts, and by integrating each part, we get:

[0106]

[0107]

[0108] in,

[0109]

[0110]

[0111]

[0112] arctan is the arctangent function.

[0113] The symbol "defined as" represents the meaning of the symbol.

[0114] (5e) f(x) obtained in (5d) i ,y i Substituting the integral result into the expression obtained in (5c), we get

[0115]

[0116] in It's about λ B A function of V and ρ Where arctanh() is the inverse hyperbolic tangent function;

[0117] (5f) By taking the mean of the distribution of variable M, the probability expression for event B is obtained as follows:

[0118]

[0119] in Let M be the probability density function of variable M. A S =4L 2 This represents the area of ​​the square target scene.

[0120] Step 6. Figure 5 As shown, in the target scene, the user's own body creates a self-blocking region with an angle of ω (0≤ω≤π / 2), and its area is:

[0121]

[0122] in, Let represent the angle between the line connecting the user and the vertex of the square scene that is blocked by the user, and the x-axis. tan() is the tangent function, and cot() is the cotangent function. Only relays located outside this region can provide the auxiliary communication services mentioned above. Therefore, the probability that N relays are located outside the self-blocking region is... Define event D as the probability that at least one relay is located outside the self-blocking area. Given event D, the conditional probability that the relay link is blocked is:

[0123] II. Application Examples. To demonstrate the inventiveness and technical value of the technical solution of this invention, this section provides application examples of the technical solution of the claims on specific products or related technologies.

[0124] Application Example 1: Live Sports Event Scenario. Live sports events demand extremely high communication transmission rates. High-bandwidth millimeter-wave communication can provide transmission rates of tens of gigabits per second, meeting the requirements of this application scenario. Since the movement of athletes on the field causes random dynamic obstruction of millimeter-wave signals, accurate channel modeling considering dynamic obstruction is necessary when designing millimeter-wave communication transmission schemes. The dynamic obstruction characteristic analysis method proposed in this invention can be directly applied to the establishment of channel models under dynamic obstruction, thereby enabling the development of more effective millimeter-wave transmission schemes and providing better communication service quality for live sports events.

[0125] Application Example 2: UAV Millimeter-Wave Communication Scenario. UAV millimeter-wave communication is a cutting-edge technology with wide applications in disaster sites and emergency communications. Similarly, in such scenarios, moving people and vehicles on the ground can severely obstruct the air-to-ground millimeter-wave communication link. By utilizing the dynamic obstruction characteristic analysis method proposed in this invention, the optimal deployment location, density, and flight trajectory of UAVs can be designed, thereby improving the transmission performance of the UAV millimeter-wave communication system.

[0126] Application Example 3: Urban Hotspot Communication Scenario. In urban hotspot communication scenarios, the surge in communication throughput within the area makes it difficult for existing non-millimeter-wave traditional communication technologies to meet the demand, thus requiring the adoption of high-bandwidth, high-speed millimeter-wave communication technology. However, in urban hotspot scenarios, the large number of people and vehicles moving on the ground causes severe obstruction of millimeter-wave signals, resulting in degraded signal transmission quality. By utilizing the dynamic obstruction characteristic analysis method proposed in this invention, a more realistic millimeter-wave channel model can be modeled, and effective millimeter-wave anti-obstruction transmission strategies can be designed to improve the user's communication experience.

[0127] It should be noted that embodiments of the present invention can be implemented in hardware, software, or a combination of both. The hardware portion can be implemented using dedicated logic; the software portion can be stored in memory and executed by a suitable instruction execution system, such as a microprocessor or dedicated-design hardware. Those skilled in the art will understand that the above-described devices and methods can be implemented using computer-executable instructions and / or included in processor control code, for example, such code provided on a carrier medium such as a disk, CD, or DVD-ROM, a programmable memory such as read-only memory (firmware), or a data carrier such as an optical or electronic signal carrier. The devices and modules of the present invention can be implemented by hardware circuitry such as very large-scale integrated circuits or gate arrays, semiconductors such as logic chips, transistors, or programmable hardware devices such as field-programmable gate arrays, programmable logic devices, etc., or by software executed by various types of processors, or by a combination of the above-described hardware circuitry and software, such as firmware.

[0128] III. Evidence of the Relevant Effects of the Embodiments. The embodiments of the present invention have achieved some positive effects during research and development or use, and indeed possess significant advantages compared to existing technologies. The following description, in conjunction with data, charts, and other materials from the experimental process, illustrates these advantages.

[0129] The effects of this invention can be further illustrated by the following simulation results:

[0130] 1. Simulation conditions

[0131] A1) Select a square area with a side length of 2L = 200m as the target scene;

[0132] A2) The movement of dynamic obstacles is simulated using a random point movement model. The movement speed is V = 0.5, 1, 1.5, 2, 2.5 m / s, and the average blocking time of the obstacle is 0.5 s.

[0133] A3) Blocker density λ B The values ​​were 0.005, 0.1, 0.015, 0.02, and 0.025 bl / m. 2 The self-blocking angle ω is 0, and π / 3;

[0134] A4) Transmitter height h T and receiver height h D Both are 1.5m high, and the height of the obstructor is h. B The relay height is 1.8m. R =1.5, 2, 2.5, 3, 3.5m;

[0135] 2. Simulation content:

[0136] B1) where the relay height h R =3m, the speed of the blocker is V = 1m / s, and the density of the blocker is λ. B The self-blocking angle ω is 0.1 and 0.5bl / m, respectively. 2 When the conditions are 0 and π / 3, the conditional blocking probability P(B|D) and relay density λ obtained by simulating the method of this invention are calculated. R The relationship between them was further investigated, and the influence of relay density dynamic blocking probability was studied. The results are as follows: Figure 6 As shown;

[0137] B2) where the relay height h R =3m, when the speed of the blocker is V = 1m / s, and the density of the blocker is λ B The self-blocking angle ω is 0.1 and 0.5bl / m, respectively. 2 When the conditional blocking probability P(B|D) and dynamic obstacle density λ are obtained by the method of this invention, and when the conditional blocking probability P(B|D) and dynamic obstacle density λ are 0 and π / 3, respectively, B The relationship between them was compared, and the results are as follows: Figure 7 As shown;

[0138] B3) Among the relay density λ R =100 / km 2 When the speed of the obstructor is V = 1 m / s and the density of the obstructor is λ B The self-blocking angle ω is 0.1 and 0.5bl / m, respectively. 2 When the conditions are 0 and π / 3, the conditional blocking probability P(B|D) obtained by the method of this invention is compared with the relay height h. R The relationship, the result is as follows Figure 8 As shown;

[0139] B4) In relay density λ R =100 / km 2 relay height h R =3m, and the density of the blockers is λ B The self-blocking angle ω is 0.1 and 0.5bl / m, respectively. 2 The effects of the velocity V of the dynamic obstacle on the conditional blocking probability P(B|D) obtained by the method of this invention at 0 and π / 3 are as follows: Figure 9 As shown.

[0140] 3. Simulation results:

[0141] Figure 6 The dynamic obstacle density λ is given. B The self-blocking angle ω is 0.1 and 0.5bl / m, respectively. 2 With 0, π / 3, moving speed V = 1 m / s, and relay height h R When the distance is 3m, the blocking probability P(B|D) calculated by the method of this invention is relative to the relay density λ. R The performance curve, from Figure 6 As can be seen, the blocking probability P(B|D) decreases with increasing relay density, indicating that using relays can effectively reduce the blocking probability of millimeter-wave communication systems. Specifically, when the relay density reaches λ... R =300 / km 2 At that time, the probability of blocking will drop to 10. -5 This means that service reliability will reach 99.999%; at the same time, it can also be seen that different λ B The effect of ω on the blocking probability;

[0142] Figure 7 The relay height h is displayed. R =3m, the speed of the blocker is V = 1m / s, and the density of the blocker is λ. B The self-blocking angle ω is 0.1 and 0.5bl / m, respectively. 2 When the conditional blocking probability P(B|D) is 0 and π / 3, it is related to the density λ of the dynamic obstacle. B The performance curves of the relationship between them, from Figure 6 As can be seen, the greater the density of obstacles, the greater the possibility of blocking the relay link. Therefore, the conditional blocking probability P(B|D) shows an upward trend. Thus, in practical applications, when the flow of people is large, more relays need to be deployed to ensure the reliability of communication.

[0143] Figure 8 It shows the different λ B And ω, the conditional blocking probability P(B|D) relative to the relay height from h RThe variation of the relay height h from 1.5, 2, 2.5, 3 to 3.5 m shows that the conditional blocking probability P(B|D) increases with the relay height h. R The probability of obstruction decreases with the increase of the relay deployment density, which means that when the traffic flow is large, in addition to increasing the relay deployment density, the present invention can also reduce the probability of obstruction by increasing the relay height.

[0144] Figure 9 The relay density λ is given R =100 / km 2 relay height h R =3m, and the density of the blockers is λ B The self-blocking angle ω is 0.1 and 0.5bl / m, respectively. 2 The performance curves showing the relationship between the conditional blocking probability P(B|D) and the speed V of the dynamic obstacle at 0 and π / 3 show that when the dynamic obstacle moves faster, more obstacles may block the communication link per unit time, so the conditional blocking probability P(B|D) shows an upward trend. It can also be seen that the method proposed in this invention is in high agreement with the simulation results.

[0145] In summary, this invention proposes a dynamic obstruction probability analysis method for millimeter-wave communication systems with relay assistance. Compared with dynamic obstruction analysis in general specific scenarios (such as urban traffic scenarios), the dynamic obstruction considered in this invention is more in line with practical applications. On the one hand, this invention considers the correlation between the uplink and downlink of the relay under dynamic obstruction, and obtains a closed-form expression for the probability of user obstruction under multiple relay connections. On the other hand, this invention also analyzes the impact of various system parameters, such as the density and speed of dynamic obstacles, and the density and height of relays, on obstruction events. The goal of this invention is to provide a scientific and accurate method for analyzing dynamic obstruction probability, so as to effectively serve and guide the deployment of multiple relays in millimeter-wave communication systems and improve the reliability of communication systems.

[0146] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications, equivalent substitutions, and improvements made by those skilled in the art within the scope of the technology disclosed in the present invention, and within the spirit and principles of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A method for analyzing dynamic blocking characteristics, characterized in that, The dynamic obstruction characteristic analysis method sets up a relay-assisted millimeter-wave communication system. First, it randomizes the movement and density of dynamic obstacles and the density and position of relays. Then, it calculates the conditional probability of a single relay link being blocked using the correlation between uplink and downlink of the relays. It calculates the conditional probability of multiple relay links being blocked using the independence between different relay links. Finally, it obtains the closed-form expression of the probability of multiple relay links being blocked through integration and Taylor expansion, and analyzes the obstruction probability in the case of user self-obstruction. The dynamic blocking characteristic analysis method specifically includes the following steps: Step 1, Millimeter Wave Transmitter Height is millimeter wave receiver Height is , and The distance between them is The midpoint of the line connecting the two points is denoted as point A. ,point With the origin of the coordinate axes as the reference point, and the point... Set the side length to be centered. The target scene is a square open area, and relays and potential dynamic obstacles are randomly distributed throughout the square area to form a communication system. Step two, the distribution of dynamic obstacles is set according to density. The Poisson point process, each obstacle with a velocity Move, direction of movement and Angle between axes obey The obstacles are evenly distributed on the surface, and their height is set to... The relay distribution is set according to the density. The Poisson point process, given the number of relays At that time, the first One relay Two-dimensional position coordinates Following a uniform distribution, for Axis coordinates and Axis coordinates All follow Uniform distribution over the interval, with the relay height set to ; Step 3, transmitter To relay Communication link and relay to receiver Communication link Both have an "effective blocking zone." When an obstacle is located within the "effective blocking zone," the communication link will be blocked. At that time, for Relay uplink, The length of the effective blocking area of ​​the link is ,in, For relay arrive The distance to the obstacle Blocking rate of the effective blocking area of ​​the link Block the obstacle The blocking process of the link is modeled as a blocking rate of and unblocked speed The alternating update process, setting events Indicates link If blocked, then within a given number of relays and relays Under the condition of two-dimensional position coordinates, the event The conditional probability of occurrence is ;for Relay downlink, Length of the effective blocking area of ​​the link ,in For relay arrive The distance to the obstacle Blocking rate of the effective blocking area of ​​the link Block the obstacle The blocking process of the link is modeled as a blocking rate of and unblocked speed The alternating update process, events Indicates link If blocked, then within a given number of relays and relays Under the condition of two-dimensional position coordinates, the event The conditional probability of occurrence is ; Step 4, Event Indicates transmitter via relay Forward to The entire communication link If blocked, then the event Among them, the event Representative link Unobstructed, and the event Complementary; event Representative link Unobstructed, and the event Complementary; This represents the intersection of two events; given the number of relays... and relays Under the condition of two-dimensional position coordinates, for the event Conditional probability of occurrence Perform calculations; Step 5: Based on the conditional probability of a single relay link being completely blocked, known from Step 4, the event... Represents all available relay forwarding links within the target scenario. , All were blocked, affecting the event. probability of occurrence Perform calculations; Step Six: In the target scenario, the user's body obstructs the view, creating an angle of... Self-blocking region, defining events This indicates that at least one relay is located outside the self-blocking area during the event. Given conditions, what is the conditional probability that all relay forwarding links are blocked? Perform the calculation.

2. The dynamic blocking characteristic analysis method as described in claim 1, characterized in that, The fourth event The conditional probability of occurrence is: 。 3. The dynamic blocking characteristic analysis method as described in claim 1, characterized in that, The probability of step five Perform the calculations as follows: (5a) Calculate the probability It represents the number of relays that can provide service given a given number of relays. and the coordinates of the relay , The conditional probability of a relay link being blocked can be expressed as the product of the conditional probabilities of a single relay link being blocked: ； (5b) Regarding step (5a) about Integrating the distribution yields the result. for: ； in, Indicates when a given number of relays is received and the ordinates of all relays The probability of conditional obstruction at that time; (5c) In step (5b) middle Also obey A uniform distribution, whose probability density function is... Through the Regarding variables Calculate the expected value of the distribution: ； in ; Indicates when a given number of relays is received The conditional probability that all relay forwarding links are blocked when the relay location is arbitrary; (5d) Regarding step (5c) We obtain the following through Taylor approximation: ； in , The above The Taylor approximation can be divided into two parts, and by integrating each part, we get: ， in, , , ， ， ， ， ， ， , , It is the arctangent function. The symbol "represented" is defined as "; then ; (5e) The result obtained in (5d) Substituting the integral result into the expression obtained in (5c), we get: ； in It is about and The function, ,in It is the inverse hyperbolic tangent function; (5f) By adjusting the variables The distribution takes the mean, and the event is obtained. The probability expression for its occurrence is: ； in For variables The probability density function, , , This represents the area of ​​the square target scene.

4. The dynamic blocking characteristic analysis method as described in claim 1, characterized in that, The conditional probability in step six The calculation is as follows: The area of ​​the self-blocking region is: ； in, The sum of the lines connecting the user to the vertices of the square scene that are blocked by the user. The angle between the axes, It is the tangent function. Given the cotangent function, only relays located outside this region can provide the auxiliary communication services mentioned above. The probability that a relay is located outside the self-blocking region is ,event This indicates that at least one relay is located outside the self-blocking area, and the probability of this occurring is... Then in the event Given that the relay link is blocked, the conditional probability is: .

5. A computer device, characterized in that, The computer device includes a memory and a processor. The memory stores a computer program, which, when executed by the processor, causes the processor to perform the steps of the dynamic blocking characteristic analysis method according to any one of claims 1 to 4.

6. A computer-readable storage medium storing a computer program, which, when executed by a processor, causes the processor to perform the steps of the dynamic blocking characteristic analysis method according to any one of claims 1 to 4.

7. An information data processing terminal, characterized in that, The information data processing terminal is used to implement the steps of the dynamic blocking characteristic analysis method according to any one of claims 1 to 4.

8. A dynamic blocking characteristic analysis system implementing the dynamic blocking characteristic analysis method according to any one of claims 1 to 4, characterized in that, The dynamic blocking characteristic analysis system includes: The randomization modeling module is used to randomize the movement and density of dynamic obstacles, as well as the density and location of relays. The conditional probability calculation module is used to calculate the conditional probability of a single relay link being blocked by utilizing the correlation between the uplink and downlink of the relay; and then to calculate the conditional probability of multiple relay links being blocked by utilizing the independence between different relay links. The blocking probability analysis module is used to obtain the closed-form probabilities of multiple relay links being blocked through integration and Taylor expansion, and to analyze the blocking probability when users self-block.

9. A millimeter-wave communication terminal, characterized in that, The millimeter-wave communication terminal is equipped with the dynamic blocking characteristic analysis system as described in claim 8.

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