Trajectory planning method, device, electronic device, storage medium and program product

Abstract

The present application relates to the field of communication technology and specifically provides a method, device, electronic device, storage medium and program product for trajectory planning. Among them, the method includes: determining the dielectric constant error set corresponding to each device candidate trajectory based on the first antenna gain of the target device, the transmission power and second antenna gain corresponding to each ground device in the target measurement environment, the physical environment information of the target measurement environment, and the set of path loss measurement values ​​corresponding to multiple device candidate trajectories; the dielectric constant error set includes the dielectric constant estimation error of multiple dielectric constant parameters in the target measurement environment; based on the dielectric constant error set corresponding to each device candidate trajectory, the target device trajectory is selected from each device candidate trajectory. In this way, a better target device trajectory can be selected based on the dielectric constant estimation error determined based on different device candidate trajectories.

Description

Technical Field

[0001] The present application relates to the field of communication technology, specifically to a trajectory planning method, device, electronic device, storage medium and program product. Background Art

[0002] In communication application scenarios, the target device (such as a drone) is usually controlled to run along a certain trajectory. During the operation of the target device, the path loss of the communication link between the target device and various ground devices in the environment is periodically collected. The dielectric constant parameters affecting the channel in the environment are estimated based on the path loss.

[0003] In traditional methods, the operating trajectory of the target device is usually not considered, which affects the estimation performance of the dielectric constant parameters. The estimation performance of the dielectric constant parameters may be poor. Therefore, how to optimize the device operating trajectory for the estimation of the dielectric constant parameters to improve the estimation performance of the dielectric constant parameters is a problem that needs to be solved. Summary of the Invention

[0004] The purpose of the embodiments of the present application is to provide a trajectory planning method, device, electronic device, storage medium and program product to solve the problem of how to optimize the device operation trajectory.

[0005] On the one hand, an embodiment of the present application provides a trajectory planning method, the method comprising:

[0006] Obtaining a first antenna gain of a target device, a transmit power and a second antenna gain corresponding to each ground device in a target measurement environment, physical environment information of the target measurement environment, and a set of path loss measurements corresponding to a plurality of candidate device trajectories; each set of path loss measurements includes the path loss of a communication link between the target device moving along the corresponding candidate device trajectory and each ground device at a plurality of time points;

[0007] Determining a dielectric constant error set corresponding to each candidate device trajectory based on a set of path loss measurements corresponding to each candidate device trajectory, a first antenna gain, a transmit power and a second antenna gain corresponding to each ground device, and physical environment information; the dielectric constant error set includes dielectric constant estimation errors of multiple dielectric constant parameters in the target measurement environment;

[0008] A target device trajectory is selected from each candidate device trajectory according to a set of dielectric constant errors corresponding to each candidate device trajectory.

[0009] In one embodiment, selecting a target device trajectory from each candidate device trajectory according to a set of dielectric constant errors corresponding to each candidate device trajectory includes:

[0010] For each set of dielectric constant errors corresponding to the candidate device trajectory, perform the following steps until the target device trajectory is determined:

[0011] After determining the dielectric constant error set, calculating the average of the dielectric constant estimation errors in the dielectric constant error set to obtain the average estimation error corresponding to the device candidate trajectory;

[0012] If it is determined that the average estimation error meets the set trajectory conditions, the device candidate trajectory is determined as the target device trajectory.

[0013] In one embodiment, selecting a target device trajectory from each candidate device trajectory according to a set of dielectric constant errors corresponding to each candidate device trajectory includes:

[0014] Determine the average estimation error corresponding to each device candidate trajectory based on the dielectric constant error set corresponding to each device candidate trajectory;

[0015] The device candidate trajectory corresponding to the minimum value of each average estimation error is determined as the target device trajectory.

[0016] In one embodiment, the physical environment information includes: environmental geometric modeling of the target measurement environment, and ray interaction information of each communication link;

[0017] Environmental geometry modeling represents the position and shape of environmental objects in the target measurement environment;

[0018] The ray interaction information includes the coordinates of the interaction points between the multiple rays of the communication link and the target measurement environment, as well as the interaction types.

[0019] In one embodiment, the path loss is a reference signal received power;

[0020] For each ground device, the reference signal received power of the target communication link between the target device and the ground device is positively correlated with the first antenna gain, the second antenna gain and transmit power of the ground device, and the path energy gain of the target communication link;

[0021] The path energy gain of the target communication link is determined based on the environment geometry modeling, the device position of the target device, the ray interaction information of the target communication link, and various dielectric constant parameters.

[0022] In one embodiment, after selecting a target device trajectory from each candidate device trajectory based on the dielectric constant error set corresponding to each candidate device trajectory, the method further includes:

[0023] Determining a set of dielectric constant estimation values ​​corresponding to the target device trajectory based on a set of path loss measurements corresponding to each candidate device trajectory, a first antenna gain, a transmit power and a second antenna gain of each ground device, and physical environment information; the dielectric constant estimation value set includes dielectric constant estimation values ​​of each dielectric constant parameter in the target measurement environment;

[0024] Determining a set of path loss estimation values ​​corresponding to the target device trajectory based on a set of dielectric constant estimation values ​​corresponding to the target device trajectory, a first antenna gain, a transmit power and a second antenna gain of the ground device, and physical environment information; the set of path loss estimation values ​​including a plurality of estimated path losses of communication links between the target device and each ground device;

[0025] A path loss estimation error is determined based on a set of path loss estimation values ​​and a set of path loss measurement values ​​corresponding to the target device trajectory.

[0026] In one embodiment, the method further comprises:

[0027] Generate a candidate device trajectory based on at least one of the following: a set movement area, a trajectory running time range, a movement number threshold, a set movement mode, a starting position range, and an ending position range.

[0028] On the one hand, an embodiment of the present application provides a trajectory planning device, including:

[0029] an acquisition unit, configured to acquire a first antenna gain of a target device, a transmit power and a second antenna gain corresponding to each ground device in a target measurement environment, physical environment information of the target measurement environment, and a set of path loss measurement values ​​corresponding to a plurality of candidate device trajectories, each set of path loss measurement values ​​comprising a path loss of a communication link between the target device moving along the corresponding candidate device trajectory and each ground device at a plurality of time points;

[0030] a determination unit, configured to determine a dielectric constant error set corresponding to each candidate device trajectory based on a set of path loss measurements corresponding to each candidate device trajectory, a first antenna gain, a transmit power and a second antenna gain corresponding to each ground device, and physical environment information; the dielectric constant error set including dielectric constant estimation errors of multiple dielectric constant parameters in a target measurement environment;

[0031] The selection unit is configured to select a target device trajectory from each of the candidate device trajectories according to a set of dielectric constant errors corresponding to each of the candidate device trajectories.

[0032] In one embodiment, the selection unit is configured to:

[0033] For each set of dielectric constant errors corresponding to the candidate device trajectory, perform the following steps until the target device trajectory is determined:

[0034] After determining the dielectric constant error set, calculating the average of the dielectric constant estimation errors in the dielectric constant error set to obtain the average estimation error corresponding to the device candidate trajectory;

[0035] If it is determined that the average estimation error meets the set trajectory conditions, the device candidate trajectory is determined as the target device trajectory.

[0036] In one embodiment, the selection unit is configured to:

[0037] Determine the average estimation error corresponding to each device candidate trajectory based on the dielectric constant error set corresponding to each device candidate trajectory;

[0038] The device candidate trajectory corresponding to the minimum value of each average estimation error is determined as the target device trajectory.

[0039] In one embodiment, the physical environment information includes: environmental geometric modeling of the target measurement environment, and ray interaction information of each communication link;

[0040] Environmental geometry modeling represents the position and shape of environmental objects in the target measurement environment;

[0041] The ray interaction information includes the coordinates of the interaction points between the multiple rays of the communication link and the target measurement environment, as well as the interaction types.

[0042] In one embodiment, the path loss is a reference signal received power;

[0043] For each ground device, the reference signal received power of the target communication link between the target device and the ground device is positively correlated with the first antenna gain, the second antenna gain and transmit power of the ground device, and the path energy gain of the target communication link;

[0044] The path energy gain of the target communication link is determined based on the environment geometry modeling, the device position of the target device, the ray interaction information of the target communication link, and various dielectric constant parameters.

[0045] In one embodiment, the selection unit is further configured to:

[0046] Determining a set of dielectric constant estimation values ​​corresponding to the target device trajectory based on a set of path loss measurements corresponding to each candidate device trajectory, a first antenna gain, a transmit power and a second antenna gain of each ground device, and physical environment information; the dielectric constant estimation value set includes dielectric constant estimation values ​​of each dielectric constant parameter in the target measurement environment;

[0047] Determining a set of path loss estimation values ​​corresponding to the target device trajectory based on a set of dielectric constant estimation values ​​corresponding to the target device trajectory, a first antenna gain, a transmit power and a second antenna gain of the ground device, and physical environment information; the set of path loss estimation values ​​including a plurality of estimated path losses of communication links between the target device and each ground device;

[0048] A path loss estimation error is determined based on a set of path loss estimation values ​​and a set of path loss measurement values ​​corresponding to the target device trajectory.

[0049] In one embodiment, the acquiring unit is further configured to:

[0050] Generate a candidate device trajectory based on at least one of the following: a set movement area, a trajectory running time range, a movement number threshold, a set movement mode, a starting position range, and an ending position range.

[0051] In one aspect, an embodiment of the present application provides an electronic device, including:

[0052] processor; and

[0053] A memory stores computer instructions, wherein the computer instructions are used to enable a processor to execute the steps of the method provided in any of the various optional implementations of trajectory planning described above.

[0054] On the one hand, an embodiment of the present application provides a computer-readable storage medium storing computer instructions, which are used to enable a computer to execute the steps of the method provided in any of the various optional implementations of trajectory planning described above.

[0055] On the one hand, an embodiment of the present application provides a computer program product, including computer-readable code, or a non-volatile computer-readable storage medium carrying computer-readable code. When the computer-readable code runs in a processor of an electronic device, the processor in the electronic device executes the steps of the method provided in any of the various optional implementations of trajectory planning described above.

[0056] The trajectory planning method in the embodiment of the present application includes obtaining the first antenna gain of the target device, the transmission power and second antenna gain corresponding to each ground device in the target measurement environment, the physical environment information of the target measurement environment, and a set of path loss measurement values ​​corresponding to each of the candidate device trajectories; each path loss measurement value set includes the path loss of the communication link between the target device moving along the corresponding device candidate trajectory and each ground device at multiple time points; based on the path loss measurement value set corresponding to each device candidate trajectory, the first antenna gain, the transmission power and second antenna gain corresponding to each ground device, and the physical environment information, the dielectric constant error set corresponding to each device candidate trajectory is determined; the dielectric constant error set includes the dielectric constant estimation error of multiple dielectric constant parameters in the target measurement environment; based on the dielectric constant error set corresponding to each device candidate trajectory, the target device trajectory is selected from each device candidate trajectory. In this way, a better target device trajectory can be selected through the dielectric constant estimation error. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] In order to more clearly illustrate the specific implementation methods of the present application or the technical solutions in the prior art, the following is a brief introduction to the drawings required for use in the specific implementation methods or the description of the prior art. Obviously, the drawings described below are some implementation methods of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0058] Figure 1 This is an example diagram of an application scenario in an embodiment of the present application.

[0059] Figure 2 This is a flow chart of a trajectory planning method in an embodiment of the present application.

[0060] Figure 3 This is a top view of a target measurement environment in an embodiment of the present application.

[0061] Figure 4 It is a three-dimensional view of a target measurement environment in an embodiment of the present application.

[0062] Figure 5 It is a curve chart of estimation error performance comparison in an embodiment of the present application.

[0063] Figure 6 This is a curve diagram of path loss estimation error in an embodiment of the present application.

[0064] Figure 7 It is a structural block diagram of a trajectory planning device in an embodiment of the present application.

[0065] Figure 8It is a structural diagram of an electronic device in an embodiment of the present application. DETAILED DESCRIPTION

[0066] The technical solutions of the present application will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application. In addition, the technical features involved in the different embodiments of the present application described below can be combined with each other as long as they do not conflict with each other.

[0067] Considering that the running trajectory of the target device will affect the estimation performance of the dielectric constant parameters, the embodiments of the present application provide a trajectory planning method, device, electronic device, storage medium and program product, aiming to solve the problem of how to optimize the running trajectory of the device.

[0068] A trajectory planning method is provided in an embodiment of the present application. The method can be applied to electronic devices. The present application does not limit the type of electronic device. It can be any type of device suitable for implementation, such as a terminal device and a server, etc. The present application will not elaborate on this.

[0069] See Figure 1 The figure shown is an example diagram of an application scenario. Figure 1 In the figure, the target measurement environment is shown, and the target measurement environment includes a drone (i.e., target device) and multiple ground devices, as well as multiple buildings (i.e., environmental objects). Each surface of the building has a corresponding dielectric constant parameter, for example, which can be expressed as ∈ 1.1 ,∈ 1.2 ,∈ 2.1 ,….

[0070] The following combination Figure 1 and Figure 2 A method for trajectory planning in an embodiment of the present application is described, see Figure 2 FIG. 1 is a flow chart of a trajectory planning method according to an embodiment of the present application. The specific implementation process of the method is as follows:

[0071] Step 201: Obtain the first antenna gain of the target device, the transmission power and second antenna gain corresponding to each ground device in the target measurement environment, the physical environment information of the target measurement environment, and a set of path loss measurement values ​​corresponding to multiple device candidate trajectories; each path loss measurement value set includes the path loss of the communication link between the target device moving according to the corresponding device candidate trajectory and each ground device at multiple time points.

[0072] The physical environment information includes: the environmental geometry modeling Benv of the target measurement environment and the ray interaction information of each communication link; the environmental geometry modeling represents the position (e.g., geographic location) and shape (e.g., building shape) of environmental objects in the target measurement environment; the ray interaction information includes the coordinates of the interaction points and interaction types between multiple rays of the communication link and the target measurement environment, which refers to the geometric information χ of the interaction between rays and the environment in ray tracing.

[0073] Optionally, the path loss can be Reference Signal Received Power (RSRP). In practical applications, path loss can also be measured using other parameters, which are not limited here. Path loss can be measured periodically. Path loss can be obtained by the target device measuring signals sent by various ground devices, or by the ground device measuring signals sent by the target device.

[0074] In one embodiment, the candidate device trajectory may be generated based on at least one of the following: a set movement area, a trajectory running time range, a movement number threshold, a set movement mode, a starting position range, and an ending position range.

[0075] Among them, the moving area is set as the moving range of the target device, which can include the ground range and the height range. For example, the entire area of ​​the target measurement environment can be determined as the set moving area. The trajectory operation time range refers to the total duration threshold of the target device trajectory movement, and can also include the start time. For example, the total duration threshold is 1 hour. The movement count threshold is the minimum and maximum value of the total number of movements during the target device trajectory movement. The setting movement mode can include flight altitude and flight speed, etc. The starting position range and the end position range are used to determine the starting position and destination of the target device trajectory movement.

[0076] In this way, candidate device trajectories that meet specific conditions can be generated according to the trajectory generation rules, that is, candidate device trajectories under conditions such as different movement modes, movement times, and end point positions can be generated.

[0077] Furthermore, in an embodiment of the present application, multiple different device candidate trajectories can be generated simultaneously, and a set of path loss measurement values ​​corresponding to each device candidate trajectory can be obtained, so as to select the optimal target device trajectory from each device candidate trajectory in a subsequent step. A loop method can also be used to generate each device candidate trajectory in turn, and based on the set of path loss measurement values ​​of the device candidate trajectory, it is determined whether it is a target device trajectory that meets the set trajectory conditions, until a target device trajectory that meets the set trajectory conditions is obtained, and the trajectory planning process is stopped.

[0078] Step 202: Determine a dielectric constant error set corresponding to each device candidate trajectory based on the path loss measurement value set corresponding to each device candidate trajectory, the first antenna gain, the transmission power and second antenna gain corresponding to each ground device, and the physical environment information; the dielectric constant error set includes the dielectric constant estimation errors of multiple dielectric constant parameters in the target measurement environment.

[0079] Combine Figure 1 As shown in Figure 1, there are multiple dielectric constant parameters in the target measurement environment. Therefore, a dielectric constant error set contains multiple dielectric constant parameters and their corresponding dielectric constant estimation errors. The dielectric constant estimation error refers to the error in the dielectric constant parameter estimation.

[0080] For each ground device, the reference signal received power of the target communication link between the target device and the ground device is positively correlated with the first antenna gain, the second antenna gain and transmit power of the ground device, and the path energy gain of the target communication link. The path energy gain of the target communication link is determined based on the environment geometry model, the device position of the target device, the ray interaction information of the target communication link, and various dielectric constant parameters. Furthermore, the reference signal received power can also be positively correlated with the error, for example, the error can be a Gaussian error in the path loss estimate.

[0081] Optionally, the following formula may be used to determine the reference signal received power:

[0082]

[0083] Where t represents the number of the time slot, i represents the number of the ground equipment, represents the reference signal received power of ground device i measured in time slot t, P i represents the transmission power of ground equipment i, G r Indicates the first antenna gain of the target device, G tr,i represents the second antenna gain of ground device i, represents the path energy gain of ground device i in time slot t in decibels (db), z t,i represents the Gaussian error between the reference signal received power and the actual reference signal received power of device i in time slot t. u[i] is the position of ground device i, u[i] = *u x [i],u y [i],u h [i]+, i∈[1,L], L is the total number of ground devices, x, y and h are the coordinate axes of the three-dimensional space coordinate system. v[t] represents the position of the target device at time slot t, v=[v x ,v y ,v h], λ represents the carrier wavelength, Represents physical environment information.

[0084] In one application scenario, t,i The variance is The normal distribution, This error may come from various sources, such as measurement errors caused by the target device, disturbances in the measurement environment, and unaccounted multipath components.

[0085] because is the superposition of different ray energies, so for the convenience of representation, we can also express The following simplified representation is made:

[0086]

[0087] Where j is the ray number, J is the total number of rays in the communication link of ground device i, g j,t,i represents the energy gain of ray j corresponding to ground device i in time slot t,

[0088] In this embodiment of the present application, the total data collection time can be discretized into T time slots. The duration ΔT of each time slot is sufficiently small that the speed of the target device within a time slot can be considered approximately constant. In this case, the multipath composition (i.e., ray composition) of each communication link remains approximately constant over the spatial scale of the target device's movement within a time slot.

[0089] At this point, the trajectory of the target device (i.e., the candidate trajectory of the device) can be described as a set of positions, which can be recorded as V = {v[t], t = 1, ..., T}. v[t] represents the location of the target device at the start time of the tth time slot. Correspondingly, the data set of reference signal received power collected from the ground device, i.e., the set of path loss measurement values, can be recorded as in, represents the average RSRP data collected by the target device from the ground device i at position v[t]. Here, the average refers to the average value of the RSRP data during the second half of the t-1th time slot and the first half of the tth time slot.

[0090] Assuming that both the target device and the ground device are equipped with GPS, their geographic locations are known, and the transmission power of the ground device is also known. Therefore, the RSRP dataset can be equivalently regarded as a set of path loss measurements. The environmental geometry modeling and ray interaction information are used to determine the multipath information of different communication links in order to calculate g j,t,i. The dielectric constant parameter is a parameter to be estimated. Environmental geometric modeling, ray interaction information and dielectric constant parameters will affect the reflection and diffraction of rays. In the embodiment of the present application, since the average received power is considered at each device position, and the phase of the multipath mainly affects the small-scale channel state rather than the average received power, when calculating the reference signal received power of the communication link, it is approximately considered that the impact of the multipath component on the path loss is the superposition of these ray energies.

[0091] It should be noted that This is considered as the Gaussian error of the average RSRP within a single time slot, rather than the error of a single RSRP measurement sample. In each time slot, the target device measures the path loss samples of the same number of ground devices. Each measurement sample is the average RSRP of the communication link between a ground device and the target device within a time slot.

[0092] In the function In the ray calculation involved, three basic rays under the vertical polarization of the antenna are considered: direct rays, reflected rays and diffracted rays. It should be noted that It also includes rays that have multiple interactions with the environment, such as those that undergo multiple reflections or are diffracted and reflected simultaneously. Note that the multipath information and The target device only needs to collect the path loss measurement value.

[0093] In this way, when different device candidate trajectories are used, multiple different dielectric constant error sets can be obtained based on the measured path loss data (ie, each path loss).

[0094] Step 203 : selecting a target device trajectory from each candidate device trajectory according to the dielectric constant error set corresponding to each candidate device trajectory.

[0095] In one embodiment, when executing step 203, any of the following methods may be used:

[0096] Method 1: Determine in turn whether each candidate device trajectory is the target device trajectory that meets the set trajectory conditions until the target device trajectory is obtained.

[0097] In one embodiment, for each set of dielectric constant errors corresponding to a candidate device trajectory, the following steps are performed until the target device trajectory is determined:

[0098] After determining the dielectric constant error set, the average value of the dielectric constant estimation errors in the dielectric constant error set is calculated to obtain the average estimation error corresponding to the device candidate trajectory; if it is determined that the average estimation error meets the set trajectory conditions, the device candidate trajectory is determined as the target device trajectory.

[0099] In one embodiment, the trajectory condition may be that the average estimation error is lower than a set error threshold, for example, the set error threshold may be 0.1. In practical applications, both the set error threshold and the set trajectory condition may be set according to the actual application scenario and are not limited here.

[0100] Method 2: Select the optimal target device trajectory from the candidate trajectories of each device.

[0101] In one embodiment, the average estimation error corresponding to each device candidate trajectory is determined based on the dielectric constant error set corresponding to each device candidate trajectory; the device candidate trajectory corresponding to the minimum value of each average estimation error is determined as the target device trajectory.

[0102] The following uses a simulation scenario to illustrate the above embodiment. Figure 3 As shown, this is a top view of a target measurement environment. Figure 3 The top view of the environmental geometric model of the target measurement environment and the distribution of ground equipment (GE) are shown. Figure 3 In the , ground equipment is marked with a solid five-pointed star, and the height of each building is marked in meters at the top of the building. Figure 4 As shown, a three-dimensional view of a target measurement environment is shown, showing the three-dimensional views of the environment geometric model at different perspectives.

[0103] Considering that the communication link between the target device and the ground device is less affected by the dielectric constant parameters of the building surfaces farther away from them, the simulation scene is a 150m×150m urban scene with a total of 7 buildings, whose heights range from 15m to 40m.

[0104] Regarding the communication link configuration, a total of 16 GEs are evenly distributed around the buildings in the scenario, providing path loss data (i.e., a set of path loss measurements) to the target device. Communication parameters consider the carrier frequency of 2.4 GHz, a commonly used frequency band for wireless communications. The ground device's transmit power, second antenna gain, and first antenna gain of the drone (i.e., the target device) as a receiver are 18 dBm, 1 dBi, and dBi, respectively. The drone's flight altitude can range from 45 to 65 meters. To prevent buildings in the scenario from becoming obstacles to the drone's flight, the drone's flight altitude is set above all buildings. If the potential obstruction posed by buildings to the drone's flight must be considered in actual operation, the drone's flight space can be adjusted by setting no-fly zones and no-fly voxel locations. The discretized grid scale in the simulation scenario can be configured as Δx = Δy = 15 meters and Δh = 10 meters.

[0105] Considering the electromagnetic characteristics of different surfaces of the same building and the limited precision of the environmental geometry modeling, it is assumed that each building surface is characterized by an equivalent relative dielectric constant parameter. For the set of dielectric constant parameters M that need to be estimated, this section considers all building surfaces in the environmental model, including Figure 3 and Figure 4 The building sides and ceilings in the figure have a total of M=35.

[0106] To calculate Wireless propagation simulation software (Wireless InSite) can be used to obtain simulated multipath information of the communication link through ray tracing and environmental geometric model, which includes the coordinates of the interaction points and interaction types of multiple rays, such as the geometric coordinates where reflection occurs and the geometric coordinates where diffraction occurs. Environmental geometric modeling is as follows: Figure 4 As shown in the figure, since the actual value of the dielectric constant parameter is unknown during offline trajectory planning, the building material used to generate multipath information is uniformly set to concrete, with a relative dielectric constant parameter ∈r = 5.24. The maximum number of reflections and diffractions per ray can be configured to 6 and 1, respectively. The total number of rays per communication link, J, can be set to 5 to provide the multipath information required for offline trajectory planning.

[0107] Since the true value (i.e., actual value) and true distribution of the dielectric constant parameters cannot be obtained in advance, each dielectric constant parameter can be set to [a, b] uniformly distributed as prior information. In order to cover the relative dielectric constant parameters of most building materials, a = 1, b = 8, Q = 3, and X MC ={2.75,4.5,6.25}. The uniform distribution variance of the dielectric constant parameter is 4.083. Q is the number of samples, X MC Represents a collection of multiple dielectric constant parameters.

[0108] Since it is hoped that more dielectric constant parameters can be detected and estimated, that is, as many parameters as possible in M ​​can be detected, c max = w = 100 is set to a value larger than the uniform distribution variance cpri = 4.083. max is the upper limit of the Cramer-Rao Bound (CRLB) variance amplitude, and w is the gain of the detection parameter.

[0109] Note that setting a larger c max The values ​​of c and w do not invalidate the optimization of the expected CRLB variance. Instead, this indicates that the priority of probing the dielectric constant parameters is higher than optimizing the expected CRLB variance. max Set equal to w, which means that the upper limit of the CRLB variance is c maxIt is consistent with the gain w of the detection parameter.

[0110] Table 1

[0111] Material Type Relative dielectric constant parameter Conductivity Brick 3.91 0.0274 Glass 6.31 0.0116 Concrete 5.24 0.0916 Marble 7.074 0.0124 Wood 1.99 0.01201 Ceiling board 1.48 0.00282 Plasterboard 2.73 0.0193

[0112] See Table 1 for an example of electromagnetic parameters of a material. Table 1 shows the electromagnetic parameters of various International Telecommunication Union (ITU) 2.4G materials used in the simulation scenario, including relative permittivity parameters and conductivity.

[0113] In order to improve the efficiency of trajectory planning, only J = 5 rays are configured. Since real wireless environments often involve more multipath, a larger number of rays can also be configured in the simulation scenario. In addition, the electromagnetic properties of materials in the real environment also include conductivity, so the conductivity setting can also be configured in the simulation scenario. Since the true value of the dielectric constant parameter is unknown, multipath information under various material settings can be configured in the simulation scenario. As an example, in order to simulate the real scenario as much as possible, 10 rays can be set for each communication link to consider more rays, and more conductivity and material types can be configured in combination with Table 1 to consider the diversity of materials and more multipath information. After collecting the path loss data in the simulation scenario, the dielectric constant parameter can be estimated based on the path loss data to obtain the average estimation error.

[0114] Alternatively, the Generalized Approximate Message Passing (GAMP) algorithm with a trust region can be used to estimate the dielectric constant parameters based on the path loss data. The parameters of this estimation algorithm are set as follows: the initial values ​​and variances of all relative dielectric constant parameters are set to 4.5 and 4, respectively. The number of iterations is Kiter = 10, the number of GAMP runs per iteration is Kgamp = 5, and the trust region length is δ tr =2, algorithm noise variance τ w =1.

[0115] Optionally, to improve the accuracy of the dielectric constant estimation error, the mean absolute error (MAE) may be used to measure the estimation error of each dielectric constant parameter, ie, the dielectric constant parameter error, through multiple simulations.

[0116] Among them, the following formula can be used to determine the dielectric constant parameter error:

[0117]

[0118] Among them, mIndicates the dielectric constant parameter error. x represents the number of experiments, X represents the error in the case of Gaussian noise. The number of experiments to collect path loss measurements in the simulation scenario, for example, X can be 5, represents the actual value of the dielectric constant parameter m, Represents an estimated value calculated based on the measured path loss.

[0119] Optionally, the following formula can be used to determine the average estimation error:

[0120]

[0121] in, is the average estimation error, M is the total number of dielectric constant parameters, m is the serial number of dielectric constant parameters, ζ m is the dielectric constant estimation error.

[0122] It should be noted that when measuring the dielectric constant parameter error, the estimated error of the dielectric constant parameter that is not detected and the dielectric constant parameter with CRLB greater than cpri is almost only related to the prior distribution information. For example, the error value of the dielectric constant parameter that is not detected will be equal to the difference between the initial value and the true value. The value of this difference cannot effectively reflect the estimation performance of the path loss data for this parameter (i.e., the dielectric constant parameter error). For the dielectric constant parameter that is not detected and the dielectric constant parameter with CRLB greater than cpri, the expected value of the prior distribution is used. Calculate the dielectric constant parameter error for these dielectric constant parameters, where, These undetected dielectric constant parameters and dielectric constant parameters with expected CRLB variance greater than cpri are also called expected invalid parameters. Their physical meaning is that compared with the parameter prior distribution variance cpri of the dielectric constant parameter itself, the dielectric constant parameters that are not expected to obtain valid observed path loss data through offline trajectory planning are considered expected valid parameters.

[0123] See Figure 5 As shown, this is a curve diagram of estimation error performance comparison. Figure 5 In FIG. 5 , the horizontal axis is the number of time slots T, and the vertical axis is the average estimation error, which shows the curves of the average estimation error determined by the embodiment of the present application and the traditional method (ie, the greedy algorithm).

[0124] In the simulation scenarios of path loss data collection with Gaussian noise σ2 = 1 and 4, an optimized trajectory with T time slots and no given end position is used to collect path loss measurements and estimate the corresponding dielectric constant parameters. Figure 5 Shows the offline planning of the UAV trajectory starting from the starting position (0, 0, 45) set to c max=w=100 and σ2=1 and the relationship between the average estimation error and the number of available time slots T in the greedy algorithm of the present application. Figure 5 As shown, under most available time slot numbers T, the method of the present application shows lower estimation error compared with the greedy algorithm. Since the expected invalid dielectric constant parameters are included in the calculation of the average estimation error, the overall estimation error is large.

[0125] In an embodiment of the present application, path loss data can be measured according to different device candidate trajectories, and the estimated error data (i.e., estimated performance) of each dielectric constant parameter can be determined based on the measured path loss data, so that the device candidate trajectory with better estimation performance can be selected as the target device trajectory, and subsequent measurement data collection can be performed through the target device trajectory.

[0126] For example, after determining the target device trajectory, the target device trajectory can be applied to scenarios such as path loss error estimation, ray tracing simulation, path loss estimation, and wireless channel map modeling.

[0127] In one implementation, the following steps may be used to determine the path loss error:

[0128] S2031: Determine a set of dielectric constant estimation values ​​corresponding to the target device trajectory based on the path loss measurement value set corresponding to each candidate device trajectory, the first antenna gain, the transmit power and second antenna gain of each ground device, and the physical environment information; the dielectric constant estimation value set includes dielectric constant estimation values ​​of each dielectric constant parameter in the target measurement environment;

[0129] S2032: Determine a set of path loss estimation values ​​corresponding to the target device trajectory based on the set of dielectric constant estimation values ​​corresponding to the target device trajectory, the first antenna gain, the transmit power and the second antenna gain of the ground device, and the physical environment information; the set of path loss estimation values ​​includes multiple estimated path losses of the communication link between the target device and each ground device;

[0130] S2033: Determine a path loss estimation error based on a set of path loss estimation values ​​and a set of path loss measurement values ​​corresponding to the target device trajectory.

[0131] The following is an example of path loss estimation. Figure 6 FIG. 1 is a graph showing a path loss estimation error. Figure 6 The horizontal axis is the number of time slots T, and the vertical axis is the path loss estimation error. Figure 6 In the figure, curves of various path loss estimation errors calculated based on the dielectric constant parameters of the concrete configuration and the true value of the dielectric constant are respectively shown.

[0132] Optionally, when determining the path loss estimation error L, the following formula may be used:

[0133]

[0134] Among them, k is the serial number of the UAV’s flight position, N NLoS is the total number of flight positions, such as N NLoS It can be 3301, is the total path loss measurement value obtained when the UAV is at flight position k, that is, the total value of the path loss of the communication link between the UAV and all ground equipment when it is at flight position k. is the total estimated value of the path loss obtained when the UAV is at the flight position k, that is, the total estimated value of the path loss of the communication link between the UAV and all ground equipment when the UAV is at the flight position k.

[0135] Figure 6 As the number of time slots T increases, the path loss estimation error calculated using the present invention approaches the path loss estimation error calculated based on the actual dielectric constant parameters. Because there are inherent systematic errors in the simulation scenario, the path loss estimation error calculated based on the actual dielectric constant parameters is not zero.

[0136] Based on the same inventive concept, the present application also provides a trajectory planning device in an embodiment. Since the principle of solving the problem by the above-mentioned device and equipment is similar to that of a trajectory planning method, the implementation of the above-mentioned device can refer to the implementation of the method, and the repeated parts will not be repeated. The device can be applied to electronic devices. This application does not limit the type of electronic device. It can be any type of device suitable for implementation, such as terminal devices and servers, etc. This application will not repeat them.

[0137] See Figure 7 FIG. 1 is a block diagram of a trajectory planning apparatus according to an embodiment of the present application. In some embodiments, the trajectory planning apparatus according to the present application example includes:

[0138] An acquisition unit 701 is configured to acquire a first antenna gain of a target device, a transmit power and a second antenna gain corresponding to each ground device in a target measurement environment, physical environment information of the target measurement environment, and a set of path loss measurement values ​​corresponding to a plurality of candidate device trajectories, each of which includes a path loss of a communication link between the target device moving along the corresponding candidate device trajectory and each ground device at a plurality of time points.

[0139] A determining unit 702 is configured to determine a set of dielectric constant errors corresponding to each candidate device trajectory based on a set of path loss measurements corresponding to each candidate device trajectory, a first antenna gain, a transmit power and a second antenna gain corresponding to each ground device, and physical environment information. The dielectric constant error set includes dielectric constant estimation errors of multiple dielectric constant parameters in the target measurement environment.

[0140] The selection unit 703 is configured to select a target device trajectory from each candidate device trajectory according to a set of dielectric constant errors corresponding to each candidate device trajectory.

[0141] In one implementation, the selection unit 703 is configured to:

[0142] For each set of dielectric constant errors corresponding to the candidate device trajectory, perform the following steps until the target device trajectory is determined:

[0143] After determining the dielectric constant error set, calculating the average of the dielectric constant estimation errors in the dielectric constant error set to obtain the average estimation error corresponding to the device candidate trajectory;

[0144] If it is determined that the average estimation error meets the set trajectory conditions, the device candidate trajectory is determined as the target device trajectory.

[0145] In one implementation, the selection unit 703 is configured to:

[0146] Determine the average estimation error corresponding to each device candidate trajectory based on the dielectric constant error set corresponding to each device candidate trajectory;

[0147] The device candidate trajectory corresponding to the minimum value of each average estimation error is determined as the target device trajectory.

[0148] In one embodiment, the physical environment information includes: environmental geometric modeling of the target measurement environment, and ray interaction information of each communication link;

[0149] Environmental geometry modeling represents the position and shape of environmental objects in the target measurement environment;

[0150] The ray interaction information includes the coordinates of the interaction points between the multiple rays of the communication link and the target measurement environment, as well as the interaction types.

[0151] In one embodiment, the path loss is a reference signal received power;

[0152] For each ground device, the reference signal received power of the target communication link between the target device and the ground device is positively correlated with the first antenna gain, the second antenna gain and transmit power of the ground device, and the path energy gain of the target communication link;

[0153] The path energy gain of the target communication link is determined based on the environment geometry modeling, the device position of the target device, the ray interaction information of the target communication link, and various dielectric constant parameters.

[0154] In one embodiment, the selection unit 703 is further configured to:

[0155] Determining a set of dielectric constant estimation values ​​corresponding to the target device trajectory based on a set of path loss measurements corresponding to each candidate device trajectory, a first antenna gain, a transmit power and a second antenna gain of each ground device, and physical environment information; the dielectric constant estimation value set includes dielectric constant estimation values ​​of each dielectric constant parameter in the target measurement environment;

[0156] Determining a set of path loss estimation values ​​corresponding to the target device trajectory based on a set of dielectric constant estimation values ​​corresponding to the target device trajectory, a first antenna gain, a transmit power and a second antenna gain of the ground device, and physical environment information; the set of path loss estimation values ​​including a plurality of estimated path losses of communication links between the target device and each ground device;

[0157] A path loss estimation error is determined based on a set of path loss estimation values ​​and a set of path loss measurement values ​​corresponding to the target device trajectory.

[0158] In one implementation, the acquiring unit 701 is further configured to:

[0159] Generate a candidate device trajectory based on at least one of the following: a set movement area, a trajectory running time range, a movement number threshold, a set movement mode, a starting position range, and an ending position range.

[0160] The trajectory planning method in the embodiment of the present application includes obtaining the first antenna gain of the target device, the transmission power and second antenna gain corresponding to each ground device in the target measurement environment, the physical environment information of the target measurement environment, and a set of path loss measurement values ​​corresponding to each of the candidate device trajectories; each path loss measurement value set includes the path loss of the communication link between the target device moving along the corresponding device candidate trajectory and each ground device at multiple time points; based on the path loss measurement value set corresponding to each device candidate trajectory, the first antenna gain, the transmission power and second antenna gain corresponding to each ground device, and the physical environment information, the dielectric constant error set corresponding to each device candidate trajectory is determined; the dielectric constant error set includes the dielectric constant estimation error of multiple dielectric constant parameters in the target measurement environment; based on the dielectric constant error set corresponding to each device candidate trajectory, the target device trajectory is selected from each device candidate trajectory. In this way, a better target device trajectory can be selected through the dielectric constant estimation error.

[0161] In an embodiment of the present application, an electronic device is provided, including:

[0162] processor; and

[0163] The memory stores computer instructions, where the computer instructions are used to enable the processor to execute the method of any of the above embodiments.

[0164] In an embodiment of the present application, a computer-readable storage medium is provided, which stores computer instructions, and the computer instructions are used to enable a computer to execute the method of any of the above-mentioned embodiments.

[0165] An embodiment of the present application also provides a computer program product, including computer-readable code, or a non-volatile computer-readable storage medium carrying computer-readable code. When the computer-readable code runs in a processor of an electronic device, the processor in the electronic device implements any of the above-mentioned methods.

[0166] Figure 8 FIG1 shows a schematic diagram of the structure of an electronic device 8000. Figure 8 As shown, the electronic device 8000 includes: a processor 8010 and a memory 8020, and optionally, may also include a power supply 8030, a display unit 8040, and an input unit 8050.

[0167] The processor 8010 is the control center of the electronic device 8000. It uses various interfaces and lines to connect various components, and performs various functions of the electronic device 8000 by running or executing software programs and / or data stored in the memory 8020, thereby monitoring the electronic device 8000 as a whole.

[0168] In the embodiment of the present application, the processor 8010 executes the various steps in the above embodiment when calling the computer program stored in the memory 8020.

[0169] Optionally, the processor 8010 may include one or more processing units. Preferably, the processor 8010 may integrate an application processor and a modem processor, wherein the application processor primarily processes the operating system, user interface, and applications, and the modem processor primarily processes wireless communications. It is understood that the modem processor may not be integrated into the processor 8010. In some embodiments, the processor and memory may be implemented on a single chip. In some embodiments, they may also be implemented on separate chips.

[0170] The memory 8020 may mainly include a program storage area and a data storage area. The program storage area may store an operating system, various applications, etc., and the data storage area may store data created based on the use of the electronic device 8000. In addition, the memory 8020 may include a high-speed random access memory and a non-volatile memory, such as at least one disk storage device, a flash memory device, or other volatile solid-state storage device.

[0171] The electronic device 8000 also includes a power supply 8030 (such as a battery) for supplying power to various components. The power supply can be logically connected to the processor 8010 through a power management system, thereby managing functions such as charging, discharging, and power consumption through the power management system.

[0172] The display unit 8040 can be used to display information input by the user or information provided to the user, as well as various menus of the electronic device 8000. In the embodiment of the present application, it is mainly used to display the display interface of each application in the electronic device 8000 and objects such as text and pictures displayed on the display interface. The display unit 8040 may include a display panel 8041. The display panel 8041 can be configured in the form of a liquid crystal display (LCD), an organic light-emitting diode (OLED), etc.

[0173] The input unit 8050 can be used to receive information such as numbers or characters input by the user. The input unit 8050 may include a touch panel 8051 and other input devices 8052. The touch panel 8051, also known as a touch screen, can receive user touch operations on or near it (for example, operations performed by the user using a finger, a stylus, or any other suitable object or accessory on or near the touch panel 8051).

[0174] Specifically, the touch panel 8051 can detect user touch operations and the signals generated by the touch operations, convert these signals into touch point coordinates, and send them to the processor 8010. It can also receive and execute commands sent by the processor 8010. In addition, the touch panel 8051 can be implemented using various types, such as resistive, capacitive, infrared, and surface acoustic wave. Other input devices 8052 can include, but are not limited to, one or more of a physical keyboard, function keys (such as volume control buttons, power buttons, etc.), a trackball, a mouse, a joystick, etc.

[0175] Of course, the touch panel 8051 can cover the display panel 8041. When the touch panel 8051 detects a touch operation on or near it, it transmits it to the processor 8010 to determine the type of touch event. Then the processor 8010 provides corresponding visual output on the display panel 8041 according to the type of touch event. Figure 8 In the embodiment, the touch panel 8051 and the display panel 8041 are two independent components to realize the input and output functions of the electronic device 8000, but in some embodiments, the touch panel 8051 and the display panel 8041 can be integrated to realize the input and output functions of the electronic device 8000.

[0176] The electronic device 8000 may also include one or more sensors, such as a pressure sensor, a gravity acceleration sensor, a proximity light sensor, etc. Of course, according to the needs of specific applications, the electronic device 8000 may also include other components such as a camera. Since these components are not the key components used in the embodiments of this application, Figure 8 It is not shown and will not be described in detail.

[0177] Those skilled in the art will understand that Figure 8 The electronic device is merely an example and does not limit the electronic device. The electronic device may include more or fewer components than shown in the figure, or may include a combination of certain components or different components.

[0178] For the convenience of description, the above parts are divided into modules (or units) according to their functions and described separately. Of course, when implementing this application, the functions of each module (or unit) can be implemented in the same or multiple software or hardware.

Claims

1. A trajectory planning method, characterized in that: The method comprises: Obtaining a first antenna gain of a target device, a transmit power and a second antenna gain corresponding to each ground device in a target measurement environment, physical environment information of the target measurement environment, and a set of path loss measurement values ​​corresponding to a plurality of candidate device trajectories, each set of path loss measurement values ​​comprising the path loss of a communication link between the target device moving along the corresponding candidate device trajectory and each ground device at a plurality of time points; Determining a dielectric constant error set corresponding to each candidate device trajectory based on a set of path loss measurements corresponding to each candidate device trajectory, the first antenna gain, the transmit power and second antenna gain corresponding to each ground device, and the physical environment information; the dielectric constant error set including dielectric constant estimation errors of multiple dielectric constant parameters in the target measurement environment; A target device trajectory is selected from each candidate device trajectory according to a set of dielectric constant errors corresponding to each candidate device trajectory.

2. The method according to claim 1, characterized in that The step of selecting a target device trajectory from each candidate device trajectory according to a set of dielectric constant errors corresponding to each candidate device trajectory includes: For each set of dielectric constant errors corresponding to the candidate device trajectory, perform the following steps until the target device trajectory is determined: After determining the dielectric constant error set, calculating an average of each dielectric constant estimation error in the dielectric constant error set to obtain an average estimation error corresponding to the device candidate trajectory; If it is determined that the average estimation error meets the set trajectory condition, the device candidate trajectory is determined as the target device trajectory.

3. The method according to claim 1, characterized in that The step of selecting a target device trajectory from each candidate device trajectory according to a set of dielectric constant errors corresponding to each candidate device trajectory includes: Determine the average estimation error corresponding to each device candidate trajectory based on the dielectric constant error set corresponding to each device candidate trajectory; The device candidate trajectory corresponding to the minimum value among the average estimation errors is determined as the target device trajectory.

4. The method according to any one of claims 1 to 3, characterized in that The physical environment information includes: environmental geometric modeling of the target measurement environment, and ray interaction information of each communication link; The environmental geometric modeling represents the position and shape of environmental objects in the target measurement environment; The ray interaction information includes coordinates of interaction points and interaction types between the plurality of rays of the communication link and the target measurement environment respectively.

5. The method according to claim 4, characterized in that The path loss is the reference signal received power; For each ground device, the reference signal received power of the target communication link between the target device and the ground device is positively correlated with the first antenna gain, the second antenna gain and the transmit power of the ground device, and the path energy gain of the target communication link; The path energy gain of the target communication link is determined based on the environment geometry modeling, the device position of the target device, the ray interaction information of the target communication link, and various dielectric constant parameters.

6. The method according to claim 5, characterized in that After selecting a target device trajectory from each candidate device trajectory based on the dielectric constant error set corresponding to each candidate device trajectory, the method further includes: Determining a set of dielectric constant estimation values ​​corresponding to the target device trajectory based on a set of path loss measurements corresponding to each candidate device trajectory, the first antenna gain, the transmit power of each ground device and the second antenna gain, and the physical environment information; the set of dielectric constant estimation values ​​including dielectric constant estimation values ​​of each dielectric constant parameter in the target measurement environment; Determining a set of path loss estimation values ​​corresponding to the target device trajectory based on a set of dielectric constant estimation values ​​corresponding to the target device trajectory, the first antenna gain, the transmit power and the second antenna gain of the ground device, and the physical environment information; the set of path loss estimation values ​​including a plurality of estimated path losses of communication links between the target device and each ground device; A path loss estimation error is determined based on a set of path loss estimation values ​​and a set of path loss measurement values ​​corresponding to the target device trajectory.

7. The method according to any one of claims 1 to 3, characterized in that The method further comprises: The candidate device trajectory is generated according to at least one of the following: a set movement area, a trajectory running time range, a movement number threshold, a set movement mode, a starting position range, and an ending position range.

8. A trajectory planning device, characterized in that: The device comprises: an acquisition unit, configured to acquire a first antenna gain of a target device, a transmit power and a second antenna gain corresponding to each ground device in a target measurement environment, physical environment information of the target measurement environment, and a set of path loss measurement values ​​corresponding to a plurality of candidate device trajectories, each set of path loss measurement values ​​comprising a path loss of a communication link between the target device moving along the corresponding candidate device trajectory and each ground device at a plurality of time points; a determining unit, configured to determine a dielectric constant error set corresponding to each candidate device trajectory based on a set of path loss measurements corresponding to each candidate device trajectory, the first antenna gain, a transmit power and a second antenna gain corresponding to each ground device, and the physical environment information; the dielectric constant error set comprising dielectric constant estimation errors of a plurality of dielectric constant parameters in the target measurement environment; The selection unit is configured to select a target device trajectory from each of the candidate device trajectories according to a set of dielectric constant errors corresponding to each of the candidate device trajectories.

9. An electronic device, characterized in that: include: processor; as well as A memory storing computer instructions, wherein the computer instructions are used to enable the processor to execute the method according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that Computer instructions are stored, and the computer instructions are used to make a computer execute the method according to any one of claims 1 to 7.

11. A computer program product, characterized in that The invention comprises a computer-readable code, or a non-volatile computer-readable storage medium carrying the computer-readable code, wherein when the computer-readable code is executed in a processor of an electronic device, the processor in the electronic device performs the method according to any one of claims 1 to 7.

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