Reconnaissance method and system for coping with low-altitude flight small target

Abstract

The invention relates to the technical field of flight target detection, and discloses a reconnaissance method and system for coping with a low-altitude flight small target, and the method comprises the steps: predicting a flight path of each detection target instance in a next detection period through analyzing the flight state information of each detection target instance in each detection time period in a target detection period; calling detection resource deployment information, considering flight state information and flight prediction path trajectory points, and selecting and distributing a detection array element planning scheme of each phased array radar node in the next detection period and a detection task executed by each detection target instance in each detection time period; a detection task is switched among different phased array radar nodes by using the constructed detection area reconnaissance list, a large number of small flight targets which are not uniformly distributed can be accurately and reasonably detected, and the reconnaissance precision and real-time performance of the low-altitude flight small targets are improved. And the communication peak pressure caused by frequent switching of the detection nodes is avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of flight target detection, and particularly to a reconnaissance method and system for dealing with small targets flying at low altitudes. Background Art

[0002] Reconnaissance of small targets flying at low altitudes refers to the process of detecting, tracking, and identifying targets with low flight altitudes (usually 0.1 - 1 kilometer above the ground / sea surface) and small radar cross-sectional areas (RCS) (such as unmanned aerial vehicles, cruise missiles, small aircraft, etc.). Such targets have characteristics such as strong concealment, complex flight trajectories, and being easily interfered by terrain / ground features, posing severe challenges to traditional radar detection.

[0003] In the prior art, the application of networked radars can utilize the characteristics of the spatial distribution of multiple radar nodes to fill the blind spots of a single radar. However, in some scenarios (especially in areas with a large number of small flying targets that are unevenly distributed), the existing networked radar technology still has the following limitations: First, in scenarios where the number of small flying targets is large and unevenly distributed, different flying targets have different flight positions, flight speeds, and detection priorities. The networked radar needs to consider the status information of different flying targets and reasonably schedule the radar resources within the region to meet the requirements of precise detection and load balancing control of different types of flying targets. Second, the flight paths of small flying targets are different. In scenarios where the number of small flying targets is large and unevenly distributed, there may be a large number of switches of small flying target detection radars in a short period, which poses a peak challenge to the communication between multiple radars in the networked radar. Without a reasonable radar scheduling and usage strategy, it will affect the accuracy and real-time performance of radar detection and tracking. Third, in the face of radar detection nodes established in a saturated manner within the monitoring region (usually, the principle of multiple coverage of the detection region needs to be satisfied. On the one hand, it solves the problem of detection blind spots, and on the other hand, the redundant backup of radar resources can avoid the detection impact caused by node failure and malfunction), it is necessary to consider factors such as the positions and detection capabilities of different radar detection nodes to improve the rationality of the utilization of detection resources.

[0004] Therefore, how to accurately and reasonably detect a large number of small flying targets that are unevenly distributed within a region, improve the reconnaissance accuracy and real-time performance for small targets flying at low altitudes, and avoid the peak communication pressure caused by frequent switching of detection nodes is a technical problem that urgently needs to be solved. Summary of the Invention

[0005] The main objective of the present invention is to provide a reconnaissance method and system for dealing with small targets flying at low altitudes, aiming to solve at least one of the above technical problems.

[0006] To achieve the above object, the present invention provides a reconnaissance method for coping with small low-flying targets, including the following steps: Receiving radar detection signals of a phased array radar network in a target detection area during a target detection period; wherein, the phased array radar network includes a plurality of first phased array radars arranged at the edge of the target detection area for collecting first radar detection signals and a plurality of second phased array radars arranged in non-edge areas of the target detection area for collecting second radar detection signals; Obtaining a reconnaissance list of the detection area in the previous detection period, and updating the reconnaissance list of the detection area according to the first radar detection signal and the second radar detection signal; Using the flight state information of each detection target instance in the updated reconnaissance list of the detection area during the target detection period to predict the flight prediction path of each detection target instance in the next detection period; wherein, the flight prediction path includes a plurality of flight prediction path trajectory points; Invoking the detection resource deployment information of the phased array radar network, extracting the detection control association information of each phased array radar node, considering the flight state information of each detection target instance during the target detection period and a plurality of flight prediction path trajectory points in the next detection period, and allocating the detection tasks of each detection target instance in each detection time period in the next detection period in the updated reconnaissance list of the detection area to the corresponding phased array radar nodes to generate a detection strategy for the phased array radar network; Based on the detection strategy of the phased array radar network, controlling each phased array radar node to perform radar detection control and detection target switching in each detection time period of the next detection period.

[0007] Optionally, the step of obtaining the reconnaissance list of the detection area in the previous detection period and updating the reconnaissance list of the detection area according to the first radar detection signal and the second radar detection signal specifically includes: Obtaining the reconnaissance list of the detection area in the previous detection period; wherein, the reconnaissance list of the detection area stores a plurality of detection target instances, and each detection target instance includes the target identifier of the detection target and the flight state information determined in the last detection time period of the previous detection period; Analyzing the flight state information of each detection target in each detection time period of the target detection period according to the first radar detection signal and the second radar detection signal; Using the flight state information to identify a first detection target entering the target detection area, a second detection target leaving the target detection area, and a third detection target always flying in the target detection area during the target detection period, and performing a first update action and a second update action on the reconnaissance list of the detection area.

[0008] Optionally, the flight state information includes a set of flight trajectory point positions, a set of flight trajectory point speeds, a target size, and a detection priority; the steps of analyzing the flight state information of each detected target in each detection period of the target detection period according to the first radar detection signal and the second radar detection signal specifically include; Analyze the radar echo signals in each detection period of the first radar detection signal and the second radar detection signal, and determine the set of flight trajectory point positions of each detected target according to the beam pointing angle when the target echo is received and the interval distance calculated using the target echo; Using the multi-moment position tracking method, calculate the flight speed of each detected target at each flight position trajectory point according to the position change amount between adjacent detection moments of the detected target in each detection period, and determine the set of flight trajectory point speeds of each detected target; Extract the radar cross-section correlation parameters in the first radar detection signal and the second radar detection signal, estimate the radar cross-section of the detected target using the radar equation, and determine the target size of each detected target; according to the set of flight trajectory point positions, the set of flight trajectory point speeds, and the target size of each detected target, assign corresponding detection priorities to each detected target according to preset rules; Construct the set of flight trajectory point positions, the set of flight trajectory point speeds, the target size, and the detection priority determined for each detected target at each detection moment in the first radar detection signal and the second radar detection signal as flight state information.

[0009] Optionally, using the flight state information, identify the first detected target that enters the target detection area, the second detected target that leaves the target detection area, and the third detected target that always flies in the target detection area during the target detection period, and perform the first update action and the second update action steps on the detection area reconnaissance list, specifically including: Obtain the flight state information of each detected target in each detection period of the target detection period, extract the set of flight trajectory point positions in the flight state information, and identify the first detected target that enters the target detection area, the second detected target that leaves the target detection area, and the third detected target that always flies in the target detection area during the target detection period; Using the target identifier of each first detected target and the flight state information corresponding to the first detected target determined according to the first radar detection signal, construct a new detected target instance and store it in the detection area reconnaissance list in the detection period corresponding to the entry of the first detected target into the target detection area; Using the target identifier of each second detected target, delete the detected target instance corresponding to the second detected target from the detection area reconnaissance list in the detection period corresponding to the departure of the second detected target from the target detection area; Using each third detection target representation and the flight state information corresponding to the third detection target determined according to the second radar detection signal, update the flight state of the detection target instance of the third detection target stored in the detection area reconnaissance list during each detection period of the target detection cycle.

[0010] Optionally, using the flight state information of each detection target instance in the updated detection area reconnaissance list during the target detection cycle, predict the flight prediction path of each detection target instance in the next detection cycle; wherein, the flight prediction path includes several flight prediction path trajectory point steps, specifically including: Obtain the flight state information of each detection target instance in the updated detection area reconnaissance list during the target detection cycle, extract the flight trajectory point position set and the flight trajectory point speed set, and construct a flight path prediction sample composed of the position feature and speed feature of each flight trajectory point. Input the flight path prediction sample into the flight path prediction model to predict the flight prediction path of each detection target instance in the next detection cycle corresponding to each detection period and including several flight prediction path trajectory points.

[0011] Optionally, before the step of inputting the flight path prediction sample into the flight path prediction model, it further includes: Obtain the historical detection data of the phased array radar network, extract the flight historical path trajectory points of each detection target instance in several historical detection cycles recorded in the historical detection data, and construct a flight path training sample based on the position feature and speed feature of each flight historical path trajectory point. Input the flight path training sample into the pre-constructed initial convolutional neural network model for training until the number of training times reaches the requirement or the model converges, and obtain the trained flight path prediction model.

[0012] Optionally, when calling the detection resource deployment information of the phased array radar network, extracting the detection control association information of each phased array radar node, considering the flight state information of each detection target instance in the target detection cycle and several flight prediction path trajectory points in the next detection cycle, and allocating the detection tasks of several detection target instances in the updated detection area reconnaissance list during each detection period in the next detection cycle to the corresponding phased array radar nodes to generate the phased array radar network detection strategy step, specifically including: Call the detection resource deployment information of the phased array radar network and extract the detection control association information of each phased array radar node; wherein, the detection control association information includes several detection element planning schemes, and each detection element planning scheme records several detection sub-arrays with different or the same number of elements, the detection distance of each detection sub-array, and the detection range of each detection sub-array. Considering the flight state information of each detected target instance in the target detection period and several flight prediction path trajectory points in the next detection period, taking that the several flight prediction path trajectory points of each detected target instance in each detection time period in the next detection period fall within the detection range corresponding to the detection sub-array of the phased array radar node assigned to it as the first constraint condition, taking that the number of array elements or detection distance of the detection sub-array of the phased array radar node assigned to each detected target instance in each detection time period in the next detection period is greater than the array element number threshold or detection distance threshold corresponding to the detection priority of the detected target instance in the flight state information as the second constraint condition, taking that the number of sub-arrays and the number of array elements of the detection sub-arrays adopted by several detected target instances assigned to each phased array radar node in each detection time period in the next detection period satisfy the detection sub-array attributes of at least one detection array element planning scheme of the phased array radar node as the third constraint condition, and taking the minimum sum of the number of times of performing the detected target instance switching actions between every two adjacent detection time periods of each phased array radar node in the next detection period as the optimization objective; Assign the detection tasks of several detected target instances in each detection time period in the next detection period in the updated detection area reconnaissance list to the detection sub-arrays of the corresponding phased array radar nodes, optimize and solve the detected target instances assigned to each detection sub-array of each phased array radar for performing detection tasks in each detection time period of the target detection period, and construct a phased array radar networking detection strategy.

[0013] Optionally, based on the phased array radar networking detection strategy, control each phased array radar node to execute the radar detection regulation and detected target switching steps in each detection time period of the next detection period, specifically including: Based on the phased array radar networking detection strategy, generate the detection array element planning strategy and detected target instance allocation strategy of each phased array radar in each detection time period of the next detection period; According to the detection array element planning strategy, control each phased array radar to perform the detection sub-array division of the corresponding detection array element planning scheme in each detection time period of the next detection period; According to the detected target instance allocation strategy, query the flight prediction path trajectory points of each detected target instance in each detection time period of the next detection period, and control each detection sub-array of each phased array radar to perform flight detection on the assigned target detection instances.

[0014] Optionally, the reconnaissance method for dealing with low-altitude flying small targets further includes: Monitor whether the flight actual path trajectory points and flight prediction path trajectory points of each detected target instance in each detection time period of the next detection period satisfy the strategy update conditions; Wherein, the policy update condition is configured such that the proportion of the interval distances between each set of corresponding path trajectory points of the actual flight path trajectory points and the predicted flight path trajectory points exceeding the error threshold is greater than the target proportion, or the interval distance of any set of corresponding path trajectory points exceeds the update trigger threshold; If so, end the phased array radar network detection control of the current detection cycle, return to execute obtaining the detection area reconnaissance list of the previous detection cycle, update the detection area reconnaissance list according to the first radar detection signal and the second radar detection signal, and regenerate the phased array radar network detection strategy according to the updated detection area reconnaissance list.

[0015] In addition, to achieve the above object, the present invention also provides a reconnaissance system for dealing with low-altitude flying small targets, including: A receiving module, configured to receive the radar detection signals of the phased array radar network in the target detection area during the target detection cycle; wherein, the phased array radar network includes a plurality of first phased array radars arranged at the edge of the target detection area for collecting the first radar detection signals and a plurality of second phased array radars arranged in the non-edge of the target detection area for collecting the second radar detection signals; An update module, configured to obtain the detection area reconnaissance list of the previous detection cycle, and update the detection area reconnaissance list according to the first radar detection signal and the second radar detection signal; A prediction module, configured to use the flight state information of each detection target instance in the target detection cycle in the updated detection area reconnaissance list to predict the flight predicted path of each detection target instance in the next detection cycle; wherein, the flight predicted path includes a plurality of flight predicted path trajectory points; An invocation module, configured to invoke the detection resource deployment information of the phased array radar network, extract the detection control association information of each phased array radar node, consider the flight state information of each detection target instance in the target detection cycle and a plurality of flight predicted path trajectory points in the next detection cycle, and allocate the detection tasks of each detection target instance in each detection time period in the next detection cycle in the updated detection area reconnaissance list to the corresponding phased array radar nodes to generate a phased array radar network detection strategy; An execution module, configured to control each phased array radar node to execute radar detection control and detection target switching in each detection time period of the next detection cycle based on the phased array radar network detection strategy.

[0016] The beneficial effects of the present invention are as follows: A reconnaissance method and system for dealing with small low-flying targets are proposed. By analyzing the flight state information of each detected target instance in each detection period within the target detection cycle, predicting the flight path of each detected target instance in the next detection cycle, calling the detection resource deployment information, considering the flight state information and the flight prediction path trajectory points, selecting and allocating the detection array element planning scheme of each phased array radar node in the next detection cycle and the detection tasks executed by each detected target instance in each detection period, and using the constructed detection area reconnaissance list to realize the switching of detection tasks between different phased array radar nodes, it can accurately and reasonably detect a large number of small flying targets with uneven distribution, improve the reconnaissance accuracy and real-time performance for small low-flying targets, and avoid the communication peak pressure caused by frequent switching of detection nodes. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a flowchart of the reconnaissance method for dealing with small low-flying targets of the present invention; Figure 2 It is a structural diagram of the reconnaissance system for dealing with small low-flying targets of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0018] In order to make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0019] An embodiment of the present invention provides a reconnaissance method for dealing with small low-flying targets, referring to Figure 1 , Figure 1 It is a schematic flow diagram of an embodiment of the reconnaissance method for dealing with small low-flying targets of the present invention.

[0020] In this embodiment, a reconnaissance method for dealing with small low-flying targets includes the following steps: S100: Receive the radar detection signals of the phased array radar network in the target detection area during the target detection cycle; wherein, the phased array radar network includes several first phased array radars arranged at the edge of the target detection area for collecting the first radar detection signals and several second phased array radars arranged in the non-edge area of the target detection area for collecting the second radar detection signals; S200: Obtain the detection area reconnaissance list of the previous detection cycle, and update the detection area reconnaissance list according to the first radar detection signal and the second radar detection signal; S300: Predict the flight prediction path of each detected target instance in the next detection period by using the flight state information of each detected target instance in the updated detection area reconnaissance list during the target detection period; wherein, the flight prediction path includes a number of flight prediction path trajectory points. S400: Invoke the detection resource deployment information of the phased array radar network, extract the detection control correlation information of each phased array radar node, consider the flight state information of each detected target instance during the target detection period and a number of flight prediction path trajectory points in the next detection period, and allocate the detection tasks of each detected target instance in the updated detection area reconnaissance list for each detection time period in the next detection period to the corresponding phased array radar nodes to generate a phased array radar network detection strategy. S500: Based on the phased array radar network detection strategy, control each phased array radar node to perform radar detection control and detection target switching during each detection time period in the next detection period.

[0021] It should be noted that in the prior art, the application of networked radars can utilize the characteristics of the spatial distribution of multiple radar nodes to fill the blind spots of a single radar. However, in some scenarios (especially in areas with a large number of small flying targets that are unevenly distributed), the existing networked radar technology still has the following limitations: First, in scenarios where the number of small flying targets is large and unevenly distributed, different flying targets have different flight positions, flight speeds, and detection priorities. The networked radar needs to consider the state information of different flying targets and reasonably schedule the radar resources within the area to meet the requirements of accurate detection and load balancing control of different types of flying targets. Second, the flight paths of small flying targets are different. In scenarios where the number of small flying targets is large and unevenly distributed, there may be a large number of switches of small flying target detection radars in a short period of time, which poses a peak challenge to the communication between multiple radars in the networked radar. Without a reasonable radar scheduling and usage strategy, the accuracy and real-time performance of radar detection and tracking will be affected. Third, in the face of radar detection nodes established in a saturated manner within the monitoring area (usually, the principle of multiple coverage of the detection area needs to be satisfied. On the one hand, it solves the problem of detection blind spots, and on the other hand, the redundant backup of radar resources can avoid the detection impact caused by node failure and malfunction), it is necessary to consider factors such as the positions and detection capabilities of different radar detection nodes to improve the rationality of the utilization of detection resources.

[0022] To solve the above problems, in this embodiment, by analyzing the flight state information of each detection target instance in each detection period within the target detection period, predicting the flight path of each detection target instance in the next detection period, calling the detection resource deployment information, considering the flight state information and the flight prediction path trajectory points, selecting and allocating the detection array element planning scheme for each phased array radar node in the next detection period and the detection tasks executed by each detection target instance in each detection period, and using the constructed detection area reconnaissance list to realize the switching of detection tasks between different phased array radar nodes, it is possible to accurately and reasonably detect a large number of small flying targets with uneven distribution, improve the reconnaissance accuracy and real-time performance for small low-altitude flying targets, and avoid the communication peak pressure caused by frequent switching of detection nodes.

[0023] In a preferred embodiment, the steps of obtaining the detection area reconnaissance list of the previous detection period and updating the detection area reconnaissance list according to the first radar detection signal and the second radar detection signal specifically include: S210: Obtain the detection area reconnaissance list of the previous detection period; wherein, the detection area reconnaissance list stores a number of detection target instances, and each detection target instance includes the target identifier of the detection target and the flight state information determined by the detection target in the last detection period of the previous detection period; S220: Analyze the flight state information of each detection target in each detection period of the target detection period according to the first radar detection signal and the second radar detection signal; S230: Use the flight state information to identify the first detection target entering the target detection area, the second detection target leaving the target detection area, and the third detection target always flying in the target detection area within the target detection period, and perform the first update action and the second update action on the detection area reconnaissance list.

[0024] In this embodiment, after receiving the first radar detection signal collected by the first phased array radar deployed at the edge of the target detection area and the second radar detection signal collected by the second phased array radar deployed at the non-edge of the target detection area, by obtaining the detection area reconnaissance list of the previous detection period and analyzing the first detection target entering the target detection area, the second detection target leaving the target detection area, and the third detection target always flying in the target detection area in the target detection period, the number of detection target instances in the detection area reconnaissance list and the flight state information of each detection target instance are updated, so as to plan the array element division and detection actions required for each detection radar node in the next detection period according to the situation of small flying targets in the target detection period.

[0025] On this basis, the flight state information includes a set of flight trajectory point positions, a set of flight trajectory point speeds, target size, and detection priority; the steps of analyzing the flight state information of each detected target in each detection period of the target detection cycle according to the first radar detection signal and the second radar detection signal specifically include; S221: Analyze the radar echo signals in each detection period of the first radar detection signal and the second radar detection signal, and determine the set of flight trajectory point positions of each detected target according to the beam pointing angle when the target echo is received and the interval distance calculated using the target echo; S222: Use the multi-moment position tracking method to calculate the flight speed of each detected target at each flight position trajectory point according to the position change amount between adjacent detection moments of the detected target in each detection period, and determine the set of flight trajectory point speeds of each detected target; S223: Extract the radar cross-section correlation parameters in the first radar detection signal and the second radar detection signal, estimate the radar cross-section of the detected target using the radar equation, and determine the target size of each detected target; according to the set of flight trajectory point positions, the set of flight trajectory point speeds, and the target size of each detected target, assign corresponding detection priorities to each detected target according to preset rules; S224: Construct the set of flight trajectory point positions, the set of flight trajectory point speeds, the target size, and the detection priority determined for each detected target at each detection moment in the first radar detection signal and the second radar detection signal into flight state information.

[0026] On this basis, using the flight state information, identify the first detected target that enters the target detection area, the second detected target that leaves the target detection area, and the third detected target that always flies in the target detection area during the target detection cycle, and perform the first update action and the second update action steps on the detection area reconnaissance list, specifically including: S231: Obtain the flight state information of each detected target in each detection period of the target detection cycle, extract the set of flight trajectory point positions in the flight state information, and identify the first detected target that enters the target detection area, the second detected target that leaves the target detection area, and the third detected target that always flies in the target detection area during the target detection cycle; S232: Use the target identifier of each first detected target and the flight state information corresponding to the first detected target determined according to the first radar detection signal to construct a new detected target instance and store it in the detection area reconnaissance list at the detection period corresponding to when the first detected target enters the target detection area; S233: Using the target identifier of each second detection target, during the detection period corresponding to the second detection target leaving the target detection area, delete the detection target instance corresponding to this second detection target from the detection area reconnaissance list; S234: Using each third detection target representation and the flight state information corresponding to the third detection target determined according to the second radar detection signal, during each detection period of the target detection cycle, update the flight state of the detection target instance of this third detection target stored in the detection area reconnaissance list.

[0027] In this embodiment, first, through the first radar detection signal and the second radar detection signal, analyze the flight state information of each detection target including the flight trajectory point position set, the flight trajectory point speed set, the target size, and the detection priority. Then, based on the flight state information, judge the flight behavior of each detection target in the target detection cycle in the target detection area (that is, whether it enters, leaves, or goes missing and remains in the target detection area), so as to realize the generation, deletion, and update of the flight state information of the detection target instances in the detection area reconnaissance list.

[0028] In a preferred embodiment, using the flight state information of each detection target instance in the updated detection area reconnaissance list in the target detection cycle, predict the flight prediction path of each detection target instance in the next detection cycle; wherein, the flight prediction path includes several flight prediction path trajectory point steps, specifically including: S310: Obtain the flight state information of each detection target instance in the updated detection area reconnaissance list in the target detection cycle, extract the flight trajectory point position set and the flight trajectory point speed set, and construct a flight path prediction sample composed of the position feature and speed feature of each flight trajectory point; S340: Input the flight path prediction sample into the flight path prediction model to predict the flight prediction path of each detection target instance in the next detection cycle corresponding to each detection period and including several flight prediction path trajectory points.

[0029] Furthermore, before the step of inputting the flight path prediction sample into the flight path prediction model, it further includes: S320: Obtain the historical detection data of the phased array radar networking, extract the flight historical path trajectory points of each detection target instance in several historical detection cycles recorded in the historical detection data, and construct a flight path training sample based on the position feature and speed feature of each flight historical path trajectory point; S330: Input the flight path training sample into the pre-constructed initial convolutional neural network model for training until the number of training times reaches the requirement or the model converges, and obtain the trained flight path prediction model.

[0030] In this embodiment, a first update action and a second update action are performed on the detection area reconnaissance list to obtain the detection area reconnaissance list of the target detection area during the target detection period. Then, by extracting the flight trajectory point position set and the flight trajectory point speed set of each detection target instance, a flight path prediction sample is constructed. By inputting the flight path prediction sample into a flight path prediction model that has been trained in advance with flight historical path trajectory points, the flight path prediction of each detection target in the next detection cycle can be realized, providing data support for generating the phased array radar networking detection strategy in the next detection cycle.

[0031] In a preferred embodiment, the detection resource deployment information of the phased array radar network is called, the detection control association information of each phased array radar node is extracted, and the flight state information of each detection target instance in the target detection cycle and several flight prediction path trajectory points in the next detection cycle are considered. The detection tasks of several detection target instances in each detection period in the next detection cycle in the updated detection area reconnaissance list are assigned to the corresponding phased array radar nodes to generate the phased array radar networking detection strategy steps, which specifically include: S410: Call the detection resource deployment information of the phased array radar network and extract the detection control association information of each phased array radar node; wherein, the detection control association information includes several detection element planning schemes, and each detection element planning scheme records several detection sub-arrays with different or the same number of elements, the detection distance of each detection sub-array, and the detection range of each detection sub-array; S420: Consider the flight state information of each detection target instance in the target detection cycle and several flight prediction path trajectory points in the next detection cycle. The first constraint condition is that the several flight prediction path trajectory points of each detection target instance in each detection period in the next detection cycle fall within the detection range corresponding to the detection sub-array of the assigned phased array radar node. The second constraint condition is that the number of elements or the detection distance of the detection sub-array of the phased array radar node assigned to each detection target instance in each detection period in the next detection cycle is greater than the corresponding number-of-elements threshold or detection-distance threshold of the detection priority in the flight state information of the detection target instance. The third constraint condition is that the number of sub-arrays and the number of elements of the detection sub-arrays adopted by several detection target instances assigned to each phased array radar node in each detection period in the next detection cycle satisfy the detection sub-array attributes of at least one detection element planning scheme of the phased array radar node. The optimization goal is to minimize the sum of the number of times of performing the detection target instance switching action between every two adjacent detection periods for each phased array radar node in the next detection cycle; S430: Allocate the detection tasks of several detection target instances in the updated detection area reconnaissance list for each detection period in the next detection cycle to the detection sub-arrays of the corresponding phased array radar nodes, optimize and solve the detection target instances allocated to each detection sub-array of each phased array radar for performing detection tasks in each detection period of the target detection cycle, and construct a phased array radar networking detection strategy.

[0032] In this embodiment, after analyzing the flight state information of each detection target instance in each detection period within the target detection cycle using the first radar detection signal and the second radar detection signal, updating the detection area reconnaissance list, and predicting the flight path of each detection target instance in the next detection cycle based on the flight state information, by invoking the detection resource deployment information of the phased array radar networking, considering the flight state information, the flight prediction path trajectory points, and the detection control correlation information of each phased array radar, with the detection area range and detection accuracy as constraints and the minimum switching times of the phased array radar detection sub-arrays as the goal, an optimization algorithm is used to select and allocate the detection array element planning scheme of each phased array radar node in the next detection cycle and the detection tasks of each detection target instance in each detection period. Using the constructed detection area reconnaissance list to realize the switching of the detection tasks of the detection target instances between different detection sub-arrays of different phased array radar nodes, it can accurately and reasonably detect a large number of small flying targets with uneven distribution within the area range, improve the reconnaissance accuracy and real-time performance for low-altitude flying small targets, and avoid the communication peak pressure caused by frequent switching of detection nodes.

[0033] In a preferred embodiment, based on the phased array radar networking detection strategy, control each phased array radar node to execute the radar detection control and detection target switching steps in each detection period of the next detection cycle, specifically including: S510: Based on the phased array radar networking detection strategy, generate the detection array element planning strategy and detection target instance allocation strategy of each phased array radar in each detection period of the next detection cycle; S520: According to the detection array element planning strategy, control each phased array radar to perform the detection sub-array division of the corresponding detection array element planning scheme in each detection period of the next detection cycle; S530: According to the detection target instance allocation strategy, query the flight prediction path trajectory points of each detection target instance in each detection period of the next detection cycle, and control each detection sub-array of each phased array radar to perform flight detection on the allocated target detection instances.

[0034] Furthermore, the reconnaissance method for dealing with low-altitude flying small targets further includes: S610: Monitor whether the actual flight path trajectory points and the predicted flight path trajectory points of each detection target instance in each detection period of the next detection cycle meet the policy update conditions; Among them, the policy update condition is configured such that the proportion of the interval distances between each group of corresponding path trajectory points of the actual flight path trajectory points and the predicted flight path trajectory points exceeding the error threshold is greater than the target proportion, or the interval distance of any group of corresponding path trajectory points exceeds the update trigger threshold; S620: If so, end the phased array radar networking detection control of the current detection cycle, return to execute the step of obtaining the detection area reconnaissance list of the previous detection cycle, update the detection area reconnaissance list according to the first radar detection signal and the second radar detection signal, and regenerate the phased array radar networking detection strategy according to the updated detection area reconnaissance list.

[0035] In this embodiment, the phased array radar networking detection strategy includes a phased array radar networking detection strategy for guiding each phased array radar to perform detection sub-array division in each detection period of the next detection cycle, and a detection target instance allocation strategy for guiding each detection sub-array of each phased array radar to perform flight detection on the assigned target detection instances. When performing radar detection regulation and detection target switching using the detection array element planning strategy and the detection target instance allocation strategy, it is also possible to trigger the step of re-updating the detection area reconnaissance list by monitoring the difference between the actual flight path trajectory points and the predicted flight path trajectory points of each detection target instance in the next detection cycle, and the action of regenerating the phased array radar networking detection strategy according to the updated detection area reconnaissance list can minimize the change of the detection target flight path trajectory points caused by various factors that may be faced during actual operation, thereby affecting the detection efficiency, detection accuracy and detection real-time performance.

[0036] Refer to Figure 2 , Figure 2 This is the structural block diagram of the embodiment of the reconnaissance system for low-altitude flying small targets of the present invention.

[0037] As Figure 2 shown, the reconnaissance system for low-altitude flying small targets proposed in the embodiment of the present invention includes: A receiving module 10 for receiving the radar detection signals of the phased array radar networking in the target detection area during the target detection cycle; among them, the phased array radar networking includes a plurality of first phased array radars arranged at the edge of the target detection area for collecting the first radar detection signals and a plurality of second phased array radars arranged in the non-edge of the target detection area for collecting the second radar detection signals; An updating module 20 for obtaining the detection area reconnaissance list of the previous detection cycle and updating the detection area reconnaissance list according to the first radar detection signal and the second radar detection signal; The prediction module 30 is configured to use the flight state information of each detected target instance in the updated detection area reconnaissance list during the target detection period to predict the flight prediction path of each detected target instance in the next detection period; wherein, the flight prediction path includes a plurality of flight prediction path trajectory points. The calling module 40 is configured to call the detection resource deployment information of the phased array radar network, extract the detection control correlation information of each phased array radar node, consider the flight state information of each detected target instance during the target detection period and a plurality of flight prediction path trajectory points in the next detection period, and allocate the detection tasks of each detected target instance in the updated detection area reconnaissance list for each detection time period in the next detection period to the corresponding phased array radar nodes, and generate a phased array radar network detection strategy. The execution module 50 is configured to control each phased array radar node to perform radar detection control and detection target switching based on the phased array radar network detection strategy for each detection time period in the next detection period.

[0038] For other embodiments or specific implementation manners of the reconnaissance system for low-altitude flying small targets of the present invention, reference may be made to the above method embodiments, and details are not described herein again.

[0039] It can be understood that in the description of this specification, the descriptions with reference to terms such as "one embodiment", "another embodiment", "other embodiments", or "the first embodiment to the Nth embodiment" mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0040] It should be noted that in this article, the term "comprising", "including" or any other variation thereof is intended to cover a non-exclusive inclusion, so that a process, method, article or system including a series of elements not only includes those elements but also includes other elements not expressly listed, or further includes elements inherent to such process, method, article or system. Without further limitation, an element defined by the statement "including one..." does not exclude the existence of additional identical elements in the process, method, article or system including the element.

[0041] The above are only the preferred embodiments of the present invention, and do not limit the patent scope of the present invention accordingly. Any equivalent structure or equivalent process transformation made by using the content of the specification and drawings of the present invention, or directly or indirectly applied in other related technical fields, shall be included in the patent protection scope of the present invention by the same token.

Claims

1. A reconnaissance method for dealing with low-altitude flying small targets, characterized in that: The following steps are involved: Receiving radar detection signals of a phased array radar network in a target detection area during a target detection period; wherein the phased array radar network includes a plurality of first phased array radars arranged at an edge of the target detection area for collecting first radar detection signals and a plurality of second phased array radars arranged at a non-edge of the target detection area for collecting second radar detection signals; Obtaining a detection area reconnaissance list of the previous detection cycle, and updating the detection area reconnaissance list according to the first radar detection signal and the second radar detection signal; Using the flight state information of each detection target instance in the updated detection area reconnaissance list in the target detection cycle, predicting the flight prediction path of each detection target instance in the next detection cycle; wherein the flight prediction path includes a plurality of flight prediction path trajectory points; Call the detection resource deployment information of the phased array radar network, extract the detection control association information of each phased array radar node, consider the flight status information of each detection target instance in the target detection cycle and several flight prediction path trajectory points in the next detection cycle, assign the detection tasks of several detection target instances in the updated detection area reconnaissance list in each detection period in the next detection cycle to the corresponding phased array radar node, and generate the phased array radar network detection strategy; Based on the phased array radar networking detection strategy, each phased array radar node is controlled to perform radar detection regulation and detection target switching in each detection period of the next detection cycle.

2. The method for detecting a small low-altitude target according to claim 1, wherein: The step of obtaining a detection area reconnaissance list of the previous detection cycle and updating the detection area reconnaissance list according to the first radar detection signal and the second radar detection signal specifically includes: Acquire a detection area reconnaissance list of the last detection cycle; wherein the detection area reconnaissance list stores a plurality of detection target instances, each detection target instance including a target identifier of the detection target and flight status information of the detection target determined in the last detection period of the last detection cycle; analyzing the flight status information of each detected target in each detection period of the target detection cycle according to the first radar detection signal and the second radar detection signal; The flight status information is used to identify the first detection target entering the target detection area, the second detection target leaving the target detection area, and the third detection target always flying in the target detection area within the target detection cycle, and the first update action and the second update action are performed on the detection area reconnaissance list.

3. The method for detecting a small low-altitude target according to claim 2, wherein: The flight status information includes a flight trajectory point position set, a flight trajectory point speed set, a target size and a detection priority; the step of analyzing the flight status information of each detected target in each detection period of the target detection cycle according to the first radar detection signal and the second radar detection signal specifically includes: Analyze the radar echo signals of each detection period in the first radar detection signal and the second radar detection signal, and determine the flight trajectory point position set of each detected target according to the beam pointing angle when the target echo is received and the interval distance calculated using the target echo; By using a multi-time position tracking method, the flight speed of each detection target at each flight position trajectory point is calculated according to the position change amount between adjacent detection moments of the detection target in each detection period, and the flight trajectory point speed set of each detection target is determined; Extracting radar cross-section correlation parameters from the first radar detection signal and the second radar detection signal, estimating the radar cross-section of the detection target using the radar equation, and determining the target size of each detection target; assigning a corresponding detection priority to each detection target according to a flight trajectory point position set, a flight trajectory point velocity set, and the target size of each detection target in accordance with a preset rule; The flight track point position set, the flight track point speed set, the target size and the detection priority of each detected target determined at each detection moment in the first radar detection signal and the second radar detection signal are constructed as flight status information.

4. The method for detecting a small low-altitude target according to claim 2, wherein: Using the flight status information, identifying a first detection target that enters a target detection area, a second detection target that leaves the target detection area, and a third detection target that always flies in the target detection area within a target detection cycle, and performing a first update action and a second update action step on a detection area reconnaissance list, specifically including: Acquire flight status information of each detection target in each detection period in the target detection cycle, extract a flight trajectory point position set in the flight status information, and identify a first detection target that enters the target detection area, a second detection target that leaves the target detection area, and a third detection target that always flies in the target detection area within the target detection cycle; Using the target identifier of each first detection target and the flight status information corresponding to the first detection target determined according to the first radar detection signal, a new detection target instance is constructed and stored in the detection area reconnaissance list during the detection period corresponding to the first detection target entering the target detection area; Using the target identifier of each second detection target, when the second detection target leaves the detection period corresponding to the target detection area, deleting the detection target instance corresponding to the second detection target from the detection area reconnaissance list; Using each third detection target representation and the flight status information corresponding to the third detection target determined according to the second radar detection signal, the flight status of the detection target instance of the third detection target stored in the detection area reconnaissance list is updated in each detection period of the target detection cycle.

5. The method for detecting a small low-altitude target according to claim 1, wherein: The flight state information of each detection target instance in the updated detection area reconnaissance list in the target detection cycle is used to predict the flight prediction path of each detection target instance in the next detection cycle; wherein the flight prediction path includes a plurality of flight prediction path trajectory point steps, specifically including: Obtain the flight status information of each detected target instance in the updated detection area reconnaissance list during the target detection cycle, extract the flight trajectory point position set and the flight trajectory point speed set, and construct a flight path prediction sample composed of the position feature and speed feature of each flight trajectory point; The flight path prediction samples are input into a flight path prediction model to predict a flight prediction path for each detection target instance in the next detection cycle corresponding to each detection period, which includes a number of flight prediction path trajectory points.

6. The method for detecting a small low-altitude target according to claim 5, characterized in that: Before the step of inputting the flight path prediction sample into the flight path prediction model, the method further includes: Acquire historical detection data of the phased array radar network, extract the flight history path trajectory points of each detection target instance in a number of historical detection cycles recorded in the historical detection data, and construct a flight path training sample based on the position characteristics and speed characteristics of each flight history path trajectory point; The flight path training samples are input into a pre-built initial convolutional neural network model for training until the number of training times reaches the requirement or the model converges, thereby obtaining a trained flight path prediction model.

7. The method for detecting a small low-altitude target according to claim 1, wherein: The detection resource deployment information of the phased array radar network is called, the detection control association information of each phased array radar node is extracted, the flight state information of each detection target instance in the target detection cycle and several flight prediction path trajectory points in the next detection cycle are considered, and the detection tasks of several detection target instances in the updated detection area reconnaissance list in each detection period in the next detection cycle are assigned to the corresponding phased array radar nodes, and the phased array radar network detection strategy steps are generated, which specifically include: Calling the detection resource deployment information of the phased array radar network, extracting the detection control association information of each phased array radar node; wherein the detection control association information includes a plurality of detection array element planning schemes, each detection array element planning scheme records a plurality of detection sub-arrays with different or the same number of array elements, the detection distance of each detection sub-array, and the detection range of each detection sub-array; Considering the flight status information of each detection target instance in the target detection cycle and several predicted flight path trajectory points in the next detection cycle, the first constraint condition is that the several predicted flight path trajectory points of each detection target instance in each detection period in the next detection cycle fall within the detection range corresponding to the detection subarray of the phased array radar node to which it is assigned, the second constraint condition is that the number of array elements or the detection distance of the detection subarray of the phased array radar node to which each detection target instance is assigned in each detection period in the next detection cycle is greater than the number of array elements threshold or the detection distance threshold corresponding to the detection priority of the detection target instance in the flight status information, the third constraint condition is that the number of subarrays and the number of array elements of the detection subarrays used by the several detection target instances assigned to each phased array radar node in each detection period in the next detection cycle meet the detection subarray attribute of at least one detection array element planning scheme of the phased array radar node, and the optimization goal is to minimize the sum of the number of times each phased array radar node performs a detection target instance switching action between each two adjacent detection periods in the next detection cycle; The detection tasks of several detection target instances in the updated detection area reconnaissance list in each detection period in the next detection cycle are assigned to the detection sub-arrays of the corresponding phased array radar nodes. The detection target instances assigned to each detection sub-array of each phased array radar for performing the detection task in each detection period of the target detection cycle are optimized, and the phased array radar network detection strategy is constructed.

8. The method for detecting a small low-altitude target according to claim 7, characterized in that: Based on the phased array radar network detection strategy, each phased array radar node is controlled to perform radar detection control and detection target switching steps in each detection period of the next detection cycle, specifically including: Based on the phased array radar network detection strategy, a detection element planning strategy and a detection target instance allocation strategy are generated for each phased array radar in each detection period of the next detection cycle; According to the detection array element planning strategy, each phased array radar is controlled to perform the detection sub-array division corresponding to the detection array element planning scheme in each detection period of the next detection cycle; According to the detection target instance allocation strategy, the flight prediction path trajectory point of each detection target instance in each detection period of the next detection cycle is queried, and each detection subarray of each phased array radar is controlled to perform flight detection on the allocated target detection instance.

9. The method for detecting a small low-altitude target according to claim 1, wherein: The method further comprises: Monitor whether the actual flight path trajectory points and the predicted flight path trajectory points of each detection target instance in each detection period of the next detection cycle meet the strategy update conditions; The strategy update condition is configured as follows: the ratio of the distance between the actual flight path trajectory points and each group of corresponding path trajectory points in the predicted flight path trajectory points exceeding the error threshold is greater than the target ratio, or the distance between any group of corresponding path trajectory points exceeds the update trigger threshold; If so, end the phased array radar network detection control of the current detection cycle, return to execute the step of obtaining the detection area reconnaissance list of the previous detection cycle, update the detection area reconnaissance list according to the first radar detection signal and the second radar detection signal, and regenerate the phased array radar network detection strategy according to the updated detection area reconnaissance list.

10. A reconnaissance system for dealing with low-altitude small targets, characterized in that: include: A receiving module, used to receive radar detection signals of a phased array radar network in a target detection area during a target detection period; wherein the phased array radar network includes a plurality of first phased array radars arranged at an edge of the target detection area for collecting first radar detection signals and a plurality of second phased array radars arranged at a non-edge of the target detection area for collecting second radar detection signals; An updating module, used for obtaining a detection area reconnaissance list of a previous detection cycle, and updating the detection area reconnaissance list according to the first radar detection signal and the second radar detection signal; A prediction module, used to predict the flight prediction path of each detection target instance in the next detection cycle by using the flight state information of each detection target instance in the updated detection area reconnaissance list in the target detection cycle; wherein the flight prediction path includes a plurality of flight prediction path trajectory points; A calling module is used to call the detection resource deployment information of the phased array radar network, extract the detection control association information of each phased array radar node, consider the flight state information of each detection target instance in the target detection cycle and several flight prediction path trajectory points in the next detection cycle, and assign the detection tasks of several detection target instances in the updated detection area reconnaissance list in each detection period in the next detection cycle to the corresponding phased array radar node, so as to generate the phased array radar network detection strategy; The execution module is used to control each phased array radar node to perform radar detection regulation and detection target switching in each detection period of the next detection cycle based on the phased array radar networking detection strategy.

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