Performance analysis method and device for unmanned aerial vehicle cooperation ultraviolet light relay communication system

Abstract

The invention discloses an unmanned aerial vehicle cooperative ultraviolet light relay communication system performance analysis method and device. The method comprises the following steps: establishing a ground-air ultraviolet light non-direct-view single link channel model under an atmospheric turbulence channel; based on a ground-air ultraviolet light non-direct-view single link channel model, respectively calculating attenuation loss caused by scattering related to a path distance and attenuation loss caused by atmospheric turbulence; modeling fading caused by atmospheric turbulence through a logarithmic normal distribution model; and respectively calculating the outage probability and the average bit error rate of the unmanned aerial vehicle cooperative ultraviolet light relay communication system considering the attenuation loss and the atmospheric turbulence. Based on a wireless ultraviolet light non-direct-view communication model, an ultraviolet light non-direct-view single scattering communication link model is established, and on the basis of the model, the influence of attenuation loss and atmospheric turbulence on the performance of an ultraviolet communication system is comprehensively considered. Therefore, the performance of the unmanned aerial vehicle cooperation ultraviolet light relay communication system can be rapidly and reliably evaluated under the complex atmospheric condition.

Description

Technical Field

[0001] The present application relates to the field of wireless ultraviolet light scattering communication technology, and specifically to a method and device for analyzing the performance of an unmanned aerial vehicle cooperative ultraviolet light relay communication system. Background Art

[0002] With the continuous development of wireless communication technology, people have higher and higher performance requirements for communication transmission rate, anti-interference ability, confidentiality, etc. In order to improve the security of information, it is necessary to comprehensively utilize and develop a variety of communication methods, requiring the communication system to have strong anti-interference, anti-detection, anti-destruction and other capabilities. Wireless ultraviolet light scattering communication is a wireless communication technology based on atmospheric particle scattering, which has the characteristics of all-weather, anti-interference and secret communication. Compared with other wireless optical communication systems, wireless ultraviolet light communication system can be applied to special application scenarios such as non-line-of-sight communication, and has a wide range of applications in both military and civilian fields. In terms of military applications, especially in special battlefield environments, wireless ultraviolet light communication can be applied to confrontation scenarios under radio silence and strong electromagnetic interference, such as cluster drone game confrontation, ultraviolet warning, unmanned boat formation operations and other special military communication occasions with high confidentiality requirements. Wireless ultraviolet light communication has a very important role in the communication applications in various fields of sea, land and air, as well as in the modern three-dimensional communication scenarios of sea, land and air. In terms of civilian applications, wireless ultraviolet light communication can be used in power line inspection, urban base station communication, fire warning and many other aspects, bringing greater convenience to people's production and life.

[0003] In addition, with the continuous advancement of unmanned aerial vehicle (UAV) technology, UAV-based communications will play a significant role in the next generation of wireless systems. Relay-assisted communication can not only reduce the path loss caused by the strong scattering effect of ultraviolet light and increase the communication range, but also further enhance the flexibility of ultraviolet light communication under complex conditions. At present, most ultraviolet light relay systems are based on traditional ground-based systems, and research on ground-to-air communications is very scarce. Compared with traditional ground relays, UAV-assisted ultraviolet communication has the inherent advantages of dynamically adjusting the optimal position and establishing non-line-of-sight scattering links.

[0004] The existing ultraviolet communication technology has the disadvantages of increased communication path loss due to the strong scattering effect of ultraviolet light, short transmission distance and small coverage. Although the use of ultraviolet relay auxiliary communication in drone communication can improve the communication distance and range, it cannot effectively evaluate the communication performance in the drone cooperative ultraviolet relay communication system. Summary of the invention

[0005] In order to solve the problem that the existing technology cannot effectively evaluate the communication performance of the UAV cooperative ultraviolet light relay communication system, the present application proposes a UAV cooperative ultraviolet light relay communication system performance analysis method and device, which can quickly and reliably evaluate the performance of the UAV cooperative ultraviolet light relay communication system under complex atmospheric conditions.

[0006] This application is implemented through the following technical solutions:

[0007] A performance analysis method for a UAV cooperative ultraviolet relay communication system, comprising:

[0008] Establish a ground-to-air UV non-line-of-sight single-link channel model under an atmospheric turbulence channel;

[0009] Based on the ground-to-air ultraviolet non-line-of-sight single-link channel model, respectively calculating the attenuation loss caused by scattering related to the path distance and the attenuation loss caused by atmospheric turbulence;

[0010] The fading caused by atmospheric turbulence is modeled by a log-normal distribution model;

[0011] The interruption probability and average bit error rate of the UAV cooperative ultraviolet relay communication system considering attenuation loss and atmospheric turbulence are calculated respectively.

[0012] In some embodiments, the UAV cooperative ultraviolet relay communication system includes a transmission source node, a destination receiver node, and a UAV relay node;

[0013] In the ground-to-air ultraviolet light non-line-of-sight single-link channel model, each non-line-of-sight link consists of two line-of-sight links, one line-of-sight link is from the transmitting source node to the common scatterer, and the atmospheric refractive index structure constant on this link changes with increasing altitude, and the other line-of-sight link is from the common scatterer to the UAV relay node. Assuming that the receiving elevation angle and the transmitting elevation angle at the UAV relay are approximately horizontal, the atmospheric refractive index structure constant on this link is approximately uniform.

[0014] In some implementations, the parameter relationship in the ground-to-air ultraviolet non-line-of-sight single-link channel model is:

[0015]

[0016] Among them, d TR represents the distance from the transmitting source node to the UAV relay node; h is the height of the UAV relay node relative to the ground; θ R and θ T ′ represents the receiving elevation angle and the transmitting elevation angle respectively; r TR represents the horizontal distance from the transmitting source node to the drone relay node; θ S represents the scattering angle, and θS =θ T ′+θ R .

[0017] In some embodiments, respectively calculating the attenuation loss caused by scattering and the attenuation loss caused by atmospheric turbulence related to the path distance includes:

[0018] The attenuation loss caused by atmospheric turbulence is calculated by the following formula

[0019]

[0020] Where k represents the wave number; represents the atmospheric refractive index structure constant; n = {R, D}; d TV Represents the distance from the transmitting source node to the common scatterer; d RV represents the distance from the public scatterer to the drone relay node;

[0021] The attenuation loss due to scattering related to the path distance is calculated by

[0022]

[0023] Among them, k s represents the atmospheric scattering coefficient; k e =k s +k a represents the atmospheric extinction coefficient, k a represents the atmospheric medium absorption coefficient; P(θ S ) indicates that in θ S The scattering phase function related to Rayleigh scattering and Mie scattering at d TR represents the distance from the transmitting source node to the drone relay node; θ R and θ T ′ represents the receiving elevation angle and the transmitting elevation angle respectively; θ S represents the scattering angle, and θ S =θ T ′+θ R β T A represents the divergence angle; r represents the effective area of ​​the receiving aperture; V represents the common scatterer volume.

[0024] In some embodiments, modeling the fading caused by atmospheric turbulence by a log-normal distribution model includes:

[0025] Under weak to moderate turbulence conditions, assuming that the irradiance fluctuation at the UV non-line-of-sight single-link receiver follows a log-normal distribution, its probability density function is expressed as:

[0026]

[0027] Where α represents the logarithmic amplitude fluctuation of the fading, which is modeled as having a mean of μ NLOS and the variance is A log-Gaussian distributed random variable.

[0028] In some embodiments, the respectively calculating the interruption probability and the average bit error rate of the UAV cooperative ultraviolet relay communication system considering attenuation loss and atmospheric turbulence includes:

[0029] The interruption probability of the UAV cooperative ultraviolet relay communication system is calculated by the following formula:

[0030]

[0031]

[0032] The average bit error rate of the UAV cooperative ultraviolet relay communication system is calculated by the following formula:

[0033]

[0034] Among them, α R represents the irradiance attenuation factor; P th It represents the power required to ensure direct non-fading transmission from the source to the destination without interruption; H R represents the normalized attenuation term; P M Indicates power margin; μ NLOS,R represents the mean value of the fading factor from the transmitting source node to the UAV relay node; σ NLOS,R represents the root mean square of the fading factor from the transmitting source node to the UAV relay node; H D represents the normalized attenuation term; μ NLOS,D represents the mean value of the fading factor from the UAV relay node to the destination receiver node; σ NLOS,D represents the root mean square of the fading factor from the UAV relay node to the destination receiver node; P T Indicates the transmit power; T b Indicates the bit time interval; and They represent the attenuation caused by the system single link scattering and the attenuation caused by the atmospheric turbulence respectively; Indicates the total attenuation of a single link; and They represent the attenuation caused by scattering of the direct link of the system and the attenuation caused by atmospheric turbulence respectively; Q(x) is a Gaussian function, u is the independent variable; P M represents the power margin; M represents the number of relay drones; represents the interruption probability of the near direct-view UV link between the mth UAV relay and the m+1th UAV relay; R e Indicates the responsivity of the UV receiver; N 0 represents the power of additive white Gaussian noise; P is the average emitted light power of each UV emitter; represents the normalized attenuation term, where represents the attenuation of the direct link from the transmitting source node to the destination receiver node; k is the approximate order; κ i (i=1,...,k) is the zero of the Hermite polynomial of order i; w i (i=1,...,k) is the weight factor approximation of the i-th order polynomial; and They represent the bit error rates of the transmission source to the UAV relay link and the UAV relay link to the receiver link respectively; is the bit error rate of the near direct-view ultraviolet link between the mth UAV relay and the m+1th UAV relay; represents the link attenuation; κ represents the zero point of the Hermite polynomial; α NLOS Represents the irradiance attenuation factor of the non-line-of-sight link.

[0035] In the second aspect, the present application proposes a performance analysis device for a UAV cooperative ultraviolet relay communication system, comprising:

[0036] The first modeling unit is used to establish a ground-to-air ultraviolet non-line-of-sight single-link channel model under an atmospheric turbulence channel;

[0037] A first calculation unit is used to calculate the attenuation loss caused by scattering and the attenuation loss caused by atmospheric turbulence related to the path distance based on the ground-air ultraviolet non-line-of-sight single-link channel model;

[0038] A second modeling unit, for modeling the fading caused by atmospheric turbulence by means of a log-normal distribution model;

[0039] And, a second calculation unit is used to respectively calculate the interruption probability and the average bit error rate of the UAV cooperative ultraviolet light relay communication system considering attenuation loss and atmospheric turbulence.

[0040] In the third aspect, the present application proposes a performance analysis system for a cooperative ultraviolet light relay communication system of a UAV, comprising an input device, an output device, a processor and a memory; by calling the operation instructions stored in the memory, the processor is used to execute the steps of the above method.

[0041] In a fourth aspect, the present application proposes an electronic device, comprising a memory and a processor, wherein the memory stores a computer program, and the processor implements the steps of the above method when executing the computer program.

[0042] In a fifth aspect, the present application proposes a computer-readable storage medium having a computer program stored thereon, wherein the computer program implements the steps of the above method when executed by a processor.

[0043] A performance analysis method for a cooperative ultraviolet relay communication system for unmanned aerial vehicles proposed in this application firstly establishes an ultraviolet non-line-of-sight single-scattering communication link model based on a wireless ultraviolet non-line-of-sight communication model, and then reconstructs a decoding and forwarding relay framework for analyzing and optimizing the design of a UAV-assisted non-line-of-sight ultraviolet communication system based on this model; then, the influence of attenuation loss and atmospheric turbulence on the performance of the ultraviolet communication system is comprehensively considered, thereby realizing a rapid and reliable evaluation of the performance of the cooperative ultraviolet relay communication system for unmanned aerial vehicles under complex atmospheric conditions;

[0044] Correspondingly, the device, system, electronic device and computer-readable storage medium proposed in this application can also achieve the same technical effects. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] The drawings described herein are used to provide a further understanding of the embodiments of the present application, constitute a part of the present application, and do not constitute a limitation on the embodiments of the present application. In the drawings:

[0046] Figure 1 A schematic diagram of the performance analysis method proposed in the embodiment of the present application;

[0047] Figure 2 This is a schematic diagram of the structure of the UAV cooperative ultraviolet relay communication system;

[0048] Figure 3 Schematic diagram of the established air-to-ground UV non-line-of-sight single-link channel model;

[0049] Figure 4 This is a schematic diagram of the performance analysis device proposed in the embodiment of the present application;

[0050] Figure 5 A schematic diagram of the performance analysis system proposed in the embodiment of the present application;

[0051] Figure 6 A schematic diagram of the principle of an electronic device proposed in an embodiment of the present application;

[0052] Figure 7 A schematic diagram of the computer-readable storage medium principle proposed in an embodiment of the present application.

[0053] Reference numerals and corresponding component names:

[0054] 400-performance analysis device, 401-first modeling unit, 402-first computing unit, 403-second modeling unit, 404-second computing unit, 500-performance analysis system, 501-input device, 502-output device, 503-processor A, 504-memory A, 600-electronic device, 610-memory B, 620-processor B, 611-computer program A, 700-computer readable storage medium, 711-computer program B. DETAILED DESCRIPTION

[0055] In order to make the objectives, technical solutions and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with examples and drawings. The illustrative implementation scheme of the present application and its description are only used to explain the present application and are not intended to limit the present application.

[0056] Example:

[0057] This embodiment proposes a performance analysis method for a UAV cooperative ultraviolet light relay communication system, which can realize a rapid and reliable evaluation of the performance of a UAV cooperative ultraviolet light relay communication system under complex atmospheric conditions.

[0058] like Figure 1 As shown, the method proposed in this embodiment includes the following steps:

[0059] Step 110, establishing a ground-to-air ultraviolet non-line-of-sight single-link channel model under an atmospheric turbulence channel.

[0060] Step 120 , based on the ground-to-air ultraviolet non-line-of-sight single-link channel model, respectively calculate the attenuation loss caused by scattering and the attenuation loss caused by atmospheric turbulence that are related to the path distance.

[0061] Step 130 , modeling the fading caused by atmospheric turbulence using a log-normal distribution model.

[0062] Step 140, respectively calculate the interruption probability and average bit error rate of the UAV cooperative ultraviolet relay communication system considering attenuation loss and atmospheric turbulence.

[0063] The performance analysis method proposed in this embodiment can effectively evaluate the communication performance of the UAV cooperative ultraviolet light relay communication system. It takes into account the flickering effect of the ultraviolet receiving signal caused by atmospheric turbulence, and can quickly and reliably evaluate the performance of the UAV cooperative ultraviolet light relay communication system under complex atmospheric conditions.

[0064] In one embodiment, a UAV cooperative ultraviolet relay communication system with decoding and forwarding, such as Figure 2As shown, the system includes a transmitting source node T, a destination receiver node D, and a drone relay node R. The transmitting source node T uses an ultraviolet (UV) light emitting diode (LED) source, and the destination receiver node D uses a photomultiplier tube (PMT) as a photon counting detector. T,D Represents the total distance from the transmitting source node T to the destination receiver node D, and the height of the drone relay node R relative to the ground is h. The communication system adopts the intensity modulation direct detection (IM / DD) technology of on-off keying (OOK). It should be noted that the ultraviolet wavelength selected in this embodiment is in the "day-blind" ultraviolet light band, and there is almost no "day-blind" ultraviolet light from the sun irradiating the near-ground atmosphere. Therefore, there is no need to consider the influence of background noise in low-altitude ultraviolet light communication. In this communication system, the ultraviolet light signal is sent by the transmitting source, and then received by the airborne ultraviolet light relay device, and decoded and forwarded, and the relay device then sends it to the receiver through the atmospheric channel.

[0065] For the airborne ultraviolet single-link communication method, the following Figure 3 The ground-to-air (ground-to-air) ultraviolet non-line-of-sight (NLOS) single-link channel model shown in FIG. 1 shows that each non-line-of-sight link can be regarded as composed of two line-of-sight links. One line-of-sight link is from the transmitting source node T to the common scatterer. Obviously, according to the Hufnagel-Valley (HV) model, the atmospheric refractive index structure constant C on this link is n 2 It changes with the increase of altitude. The other direct-line link is from the public scatterer to the drone relay node R. Assuming that the receiving elevation angle and the transmitting elevation angle at the drone relay are approximately horizontal, the atmospheric refractive index structure constant on this link can be approximately regarded as uniform. Figure 3 Medium, d TR represents the distance from the transmitting source node T to the drone relay node R; d TV represents the distance from the transmitting source node T to the common scatterer; d RV represents the distance from the public scatterer to the drone relay node R; θ R and θ T ′ represents the receiving elevation angle and the transmitting elevation angle respectively; θ S represents the scattering angle, and θ S =θ T ′+θ R ; r TR represents the horizontal distance from the transmitting source node T to the drone relay node R; β R and β T They represent the receiving field of view (FOV) and divergence angle respectively. From the trigonometric relationship, we can know that these parameters have the following relationship:

[0066]

[0067] In one embodiment, the calculation process of step 120 includes the following steps:

[0068] Step 121, the attenuation loss caused by atmospheric turbulence is calculated by the following formula:

[0069]

[0070] Where k represents the wave number, that is, k = 2π / λ, λ represents the wavelength of the ultraviolet light signal; n = {R, D}, where R represents the drone relay node and D represents the destination receiver node; C n 2 represents the atmospheric refractive index structure constant, which is 10 -17 m -2 / 3 to 10 -13 m -2 / 3 Changes between.

[0071] Among them, according to Figure 2 The ground-to-air ultraviolet non-line-of-sight single-link channel model shown in the figure calculates the distance d from the transmitting source node T to the common scatterer. TV and the distance d from the public scatterer to the drone relay node R RV :

[0072]

[0073] Step 122, calculate the attenuation loss caused by scattering related to the path distance by the following formula:

[0074]

[0075] Among them, k s represents the atmospheric scattering coefficient; k e =k s +k a represents the atmospheric extinction coefficient, k a represents the atmospheric medium absorption coefficient; P(θ S ) indicates that in θ S The scattering phase function related to Rayleigh scattering and Mie scattering at A r represents the effective area of ​​the receiving aperture; V represents the common scatterer volume.

[0076] In one embodiment, the specific implementation process of step 130 is as follows:

[0077] Under weak to moderate turbulence conditions, assuming that the irradiance fluctuation at the UV non-line-of-sight single-link receiver follows a log-normal distribution, its probability density function (PDF) is obtained by the following formula:

[0078]

[0079] Where α represents the logarithmic amplitude fluctuation of the fading, which is modeled as having a mean of μ NLOS and the variance is is a log-Gaussian distributed random variable. Assume In order to normalize the fading amplitude, μ NLOS =μ dTV +μ dRV , for a plane wave propagating through a turbulent atmosphere, the logarithmic amplitude variance can be expressed as:

[0080]

[0081] in, They represent the variance of the direct-line link from the transmitting source node to the public scatterer and the variance of the direct-line link from the public scatterer to the UAV relay node respectively; They represent the mean of the direct-line link from the transmitting source node to the public scatterer and the mean of the direct-line link from the public scatterer to the UAV relay node, respectively.

[0082] In one embodiment, the specific implementation process of step 140 is as follows:

[0083] Step 141, calculating the interruption probability of the UAV cooperative ultraviolet relay communication system.

[0084] The outage probability is a key performance indicator for describing relay-assisted NLUV systems. In a DF (Decode-and-Forward) relay, the outage probability is defined as the instantaneous received signal-to-noise ratio γ is lower than the threshold signal-to-noise ratio γ th If γ exceeds γ th , then no interruption occurs, and the signal can be decoded with an arbitrarily small error probability. If the UAV relay-assisted non-direct-view UV system cannot transmit the signal sent by the source node to the destination node, the system will be interrupted. The interruption probability P out The calculation is as follows:

[0085]

[0086]

[0087] Among them, α R represents the irradiance attenuation factor; P th represents the power required to ensure that there is no interruption in the direct non-fading transmission from the source to the destination; Formula (8) is the formula for calculating the interruption probability of a single link, and Formula (9) is the formula for calculating the end-to-end interruption probability of the entire interruption system; H R represents the normalized attenuation term; P M Indicates power margin; μNLOS,R represents the mean value of the fading factor from the transmitting source node to the UAV relay node; σ NLOS,R represents the root mean square of the fading factor from the transmitting source node to the UAV relay node; H D represents the normalized attenuation term; μ NLOS,D represents the mean value of the fading factor from the UAV relay node to the destination receiver node; σ NLOS,D represents the root mean square of the fading factor from the UAV relay node to the destination receiver node; P T Indicates the transmit power; T b Indicates the bit time interval; and They represent the attenuation caused by the system single link scattering and the attenuation caused by the atmospheric turbulence, respectively, and are calculated by the above equations (4) and (2); Indicates the total attenuation of a single link; and They represent the attenuation caused by scattering of the system direct link and the attenuation caused by atmospheric turbulence respectively; Q(x) is a Gaussian function, u is the independent variable, and u is integrated.

[0088] Step 142, calculating the average bit error rate of the UAV cooperative ultraviolet light relay communication system.

[0089] Average bit error rate P ABER The calculation is as follows:

[0090]

[0091] Among them, P M represents the power margin; M represents the number of relay drones; represents the interruption probability of the near direct-view UV link between the mth UAV relay and the m+1th UAV relay; R e represents the responsivity of the UV receiver; P is the average emitted light power of each UV emitter; represents the normalized attenuation term, where represents the attenuation of the direct link from the transmitting source node to the destination receiver node; k is the approximate order; κ i (i=1,...,k) is the zero of the Hermite polynomial of order i; w i (i=1,...,k) is the weight factor approximation of the i-th order polynomial; and They represent the bit error rates of the transmission source to the UAV relay link and the UAV relay link to the receiver link respectively; is the bit error rate of the near direct-view ultraviolet link between the mth UAV relay and the m+1th UAV relay; represents the link attenuation; κ represents the zero point of the Hermite polynomial; N0 represents the power of additive Gaussian white noise; α NLOS Represents the irradiance attenuation factor of the non-line-of-sight link.

[0092] This embodiment also proposes an embodiment of a UAV cooperative ultraviolet relay communication system performance analysis device 200, such as Figure 4 As shown, the analysis device 400 includes:

[0093] The first modeling unit 401 is used to establish a ground-to-air ultraviolet light non-line-of-sight single-link channel model under an atmospheric turbulence channel. The established ground-to-air ultraviolet light non-line-of-sight single-link channel model is as described in the above steps 110 and Figure 3 As shown in , I will not go into details here.

[0094] The first calculation unit 402 is used to calculate the attenuation loss caused by scattering and atmospheric turbulence related to the path distance based on the ground-air ultraviolet non-line-of-sight single link channel model. The specific calculation method is as described in the above step 120 and will not be repeated here.

[0095] The second modeling unit 403 is used to model the fading caused by atmospheric turbulence by using a log-normal distribution model. The specific modeling process is as described in the above step 130, which will not be described in detail here.

[0096] And, the second calculation unit 404 is used to respectively calculate the interruption probability and average bit error rate of the UAV cooperative ultraviolet relay communication system considering attenuation loss and atmospheric turbulence. The specific calculation process is as described in the above step 140, which will not be repeated here.

[0097] This embodiment also proposes an embodiment of a UAV cooperative ultraviolet relay communication system performance analysis system 500, such as Figure 5 As shown, the analysis system 500 proposed in this embodiment includes:

[0098] Input device 501, output device 502, processor A503 and memory A504; wherein the number of processor 503 and memory can be one or more, Figure 5 The input device 501, the output device 502, the processor A503 and the memory A504 are connected by a bus or other means. Figure 5 The example of connecting through bus is taken in the following.

[0099] Wherein, by calling the operation instruction stored in the memory A504, the processor A503 is used to perform the following steps:

[0100] Establish a ground-to-air UV non-line-of-sight single-link channel model under an atmospheric turbulence channel;

[0101] Based on the ground-to-air ultraviolet non-line-of-sight single-link channel model under the atmospheric turbulence channel, the attenuation loss caused by scattering related to the path distance and the attenuation loss caused by atmospheric turbulence are calculated respectively.

[0102] The fading caused by atmospheric turbulence is modeled by a log-normal distribution model;

[0103] The interruption probability and average bit error rate of the UAV cooperative ultraviolet relay communication system considering attenuation loss and atmospheric turbulence are calculated respectively.

[0104] Optionally, by calling the operation instructions stored in the memory A504, the processor A503 is also used to execute any implementation method in the corresponding embodiments of the above-mentioned analysis method.

[0105] This embodiment also provides an embodiment of an electronic device 600, such as Figure 6 As shown, the electronic device 600 includes: a memory B610, a processor B620, and a computer program A611 stored in the memory B610 and executable on the processor B620. When the processor B620 executes the computer program A611, the following steps are implemented:

[0106] Establish a ground-to-air UV non-line-of-sight single-link channel model under an atmospheric turbulence channel;

[0107] Based on the ground-to-air ultraviolet non-line-of-sight single-link channel model under the atmospheric turbulence channel, the attenuation loss caused by scattering related to the path distance and the attenuation loss caused by atmospheric turbulence are calculated respectively.

[0108] The fading caused by atmospheric turbulence is modeled by a log-normal distribution model;

[0109] The interruption probability and average bit error rate of the UAV cooperative ultraviolet relay communication system considering attenuation loss and atmospheric turbulence are calculated respectively.

[0110] Optionally, when processor B620 executes computer program A611, any implementation method corresponding to the above-mentioned analysis method can be implemented.

[0111] It should be noted that the electronic device proposed in this embodiment is a device used to implement the above-mentioned analysis method. Therefore, based on the above-mentioned analysis method proposed in this embodiment, technical personnel in this field can understand the specific implementation mode of the electronic device of this embodiment and its various variations. Therefore, how the electronic system specifically implements the above-mentioned analysis method will not be introduced in detail here. As long as the electronic device used by technical personnel in this field to implement the above-mentioned analysis method falls within the scope of protection of this application.

[0112] This embodiment also provides an embodiment of a computer-readable storage medium 700, such as Figure 7 As shown, the computer readable storage medium 700 stores a computer program B711, and when the computer program B711 is executed by the processor, the following steps are implemented:

[0113] Establish a ground-to-air UV non-line-of-sight single-link channel model under an atmospheric turbulence channel;

[0114] Based on the ground-to-air ultraviolet non-line-of-sight single-link channel model under the atmospheric turbulence channel, the attenuation loss caused by scattering related to the path distance and the attenuation loss caused by atmospheric turbulence are calculated respectively.

[0115] The fading caused by atmospheric turbulence is modeled by a log-normal distribution model;

[0116] The interruption probability and average bit error rate of the UAV cooperative ultraviolet relay communication system considering attenuation loss and atmospheric turbulence are calculated respectively.

[0117] Optionally, when the computer program B711 is executed by a processor, any implementation method in the embodiments corresponding to the above-mentioned analysis method can be implemented.

[0118] It should be noted that in the above embodiments, the description of each embodiment has its own emphasis, and for parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0119] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented in one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that include computer-usable program code.

[0120] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0121] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0122] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0123] The specific implementation methods described above further illustrate the purpose, technical solutions and beneficial effects of the present application in detail. It should be understood that the above description is only the specific implementation method of the present application and is not intended to limit the scope of protection of the present application. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application should be included in the scope of protection of the present application.

Claims

1. A performance analysis method for a UAV cooperative ultraviolet relay communication system, characterized in that: include: Establish a ground-to-air UV non-line-of-sight single-link channel model under an atmospheric turbulence channel; Based on the ground-to-air ultraviolet non-line-of-sight single-link channel model, respectively calculating the attenuation loss caused by scattering related to the path distance and the attenuation loss caused by atmospheric turbulence; The fading caused by atmospheric turbulence is modeled by a log-normal distribution model; The interruption probability and average bit error rate of the UAV cooperative ultraviolet relay communication system considering attenuation loss and atmospheric turbulence are calculated respectively.

2. The method for analyzing the performance of a UAV cooperative ultraviolet relay communication system according to claim 1 is characterized in that: The UAV cooperative ultraviolet light relay communication system comprises a transmitting source node, a destination receiver node and a UAV relay node; In the ground-to-air ultraviolet light non-line-of-sight single-link channel model, each non-line-of-sight link consists of two line-of-sight links, one line-of-sight link is from the transmitting source node to the common scatterer, and the atmospheric refractive index structure constant on this link changes with increasing altitude, and the other line-of-sight link is from the common scatterer to the UAV relay node. Assuming that the receiving elevation angle and the transmitting elevation angle at the UAV relay are approximately horizontal, the atmospheric refractive index structure constant on this link is approximately uniform.

3. The method for analyzing the performance of a UAV cooperative ultraviolet relay communication system according to claim 2 is characterized in that: The parameter relationship in the ground-to-air ultraviolet non-line-of-sight single-link channel model is: Among them, d TR represents the distance from the transmitting source node to the UAV relay node; h is the height of the UAV relay node relative to the ground; θ R and θ T ′ represents the receiving elevation angle and the transmitting elevation angle respectively; r TR represents the horizontal distance from the transmitting source node to the UAV relay node; θ S represents the scattering angle, and θ S =θ T ′+θ R .

4. A method for analyzing the performance of a UAV cooperative ultraviolet relay communication system according to any one of claims 1 to 3, characterized in that: The attenuation loss caused by scattering and the attenuation loss caused by atmospheric turbulence respectively calculated in relation to the path distance include: The attenuation loss caused by atmospheric turbulence is calculated by the following formula Where k represents the wave number; represents the atmospheric refractive index structure constant; n = {R, D}; d TV Represents the distance from the transmitting source node to the common scatterer; d RV represents the distance from the public scatterer to the drone relay node; The attenuation loss due to scattering related to the path distance is calculated by Among them, k s represents the atmospheric scattering coefficient; k e =k s +k a represents the atmospheric extinction coefficient, k a represents the atmospheric medium absorption coefficient; P(θ S ) indicates that in θ S The scattering phase function related to Rayleigh scattering and Mie scattering at d TR represents the distance from the transmitting source node to the drone relay node; θ R and θ T ′ represents the receiving elevation angle and the transmitting elevation angle respectively; θ S represents the scattering angle, and θ S =θ T ′+θ R β T A represents the divergence angle; r represents the effective area of ​​the receiving aperture; V represents the common scatterer volume.

5. A method for analyzing the performance of a UAV cooperative ultraviolet relay communication system according to any one of claims 1 to 3, characterized in that: The method of modeling the fading caused by atmospheric turbulence by using a log-normal distribution model includes: Under weak to moderate turbulence conditions, assuming that the irradiance fluctuation at the UV non-line-of-sight single-link receiver follows a log-normal distribution, its probability density function is expressed as: Where α represents the logarithmic amplitude fluctuation of the fading, which is modeled as having a mean of μ NLOS and the variance is A log-Gaussian distributed random variable.

6. A method for analyzing the performance of a UAV cooperative ultraviolet relay communication system according to any one of claims 1 to 3, characterized in that: The aforementioned methods of respectively calculating the interruption probability and the average bit error rate of the UAV cooperative ultraviolet relay communication system considering attenuation loss and atmospheric turbulence include: The interruption probability of the UAV cooperative ultraviolet relay communication system is calculated by the following formula: The average bit error rate of the UAV cooperative ultraviolet relay communication system is calculated by the following formula: Among them, α R represents the irradiance attenuation factor; P th It represents the power required to ensure direct non-fading transmission from the source to the destination without interruption; H R represents the normalized attenuation term; P M Indicates power margin; μ NLOS,R represents the mean value of the fading factor from the transmitting source node to the UAV relay node; σ NLOS,R represents the root mean square of the fading factor from the transmitting source node to the UAV relay node; H D represents the normalized attenuation term; μ NLOS,D represents the mean value of the fading factor from the UAV relay node to the destination receiver node; σ NLOS,D represents the root mean square of the fading factor from the UAV relay node to the destination receiver node; P T Indicates the transmit power; T b Indicates the bit time interval; and They represent the attenuation caused by the system single link scattering and the attenuation caused by the atmospheric turbulence respectively; Indicates the total attenuation of a single link; and They represent the attenuation caused by scattering of the direct link of the system and the attenuation caused by atmospheric turbulence respectively; Q(x) is a Gaussian function, u is the independent variable; P M represents the power margin; M represents the number of relay drones; represents the interruption probability of the near-direct-view UV link between the mth UAV relay and the m+1th UAV relay; R e represents the responsivity of the UV receiver; N0 represents the power of additive white Gaussian noise; P is the average light power emitted by each UV transmitter; represents the normalized attenuation term, where represents the attenuation of the direct link from the transmitting source node to the destination receiver node; k is the approximate order; κ i (i=1,...,k) is the zero of the Hermite polynomial of order i; w i (i=1,...,k) is the weight factor approximation of the i-th order polynomial; P e U and P e D They represent the bit error rates of the transmission source to the UAV relay link and the UAV relay link to the receiver link respectively; P e m,m+1 is the bit error rate of the near direct-view ultraviolet link between the mth UAV relay and the m+1th UAV relay; represents the link attenuation; κ represents the zero point of the Hermite polynomial; α NLOS Represents the irradiance attenuation factor of the non-line-of-sight link.

7. A performance analysis device for a cooperative ultraviolet relay communication system of unmanned aerial vehicles, characterized in that: include: The first modeling unit is used to establish a ground-to-air ultraviolet non-line-of-sight single-link channel model under an atmospheric turbulence channel; A first calculation unit is used to calculate the attenuation loss caused by scattering and the attenuation loss caused by atmospheric turbulence related to the path distance based on the ground-air ultraviolet non-line-of-sight single-link channel model; A second modeling unit, for modeling the fading caused by atmospheric turbulence by a log-normal distribution model; And, a second calculation unit is used to respectively calculate the interruption probability and the average bit error rate of the UAV cooperative ultraviolet light relay communication system considering attenuation loss and atmospheric turbulence.

8. A UAV cooperative ultraviolet relay communication system performance analysis system, comprising an input device, an output device, a processor and a memory; characterized in that: By calling the operation instructions stored in the memory, the processor is used to execute the steps of the method according to any one of claims 1 to 6.

9. An electronic device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 6 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 6 are implemented.

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