CN113640788A

CN113640788A - Target tracking method

Info

Publication number: CN113640788A
Application number: CN202110972796.7A
Authority: CN
Inventors: 王昊; 潘黎; 徐达龙; 王岩; 徐文文; 权双龙; 陶诗飞
Original assignee: Nanjing University of Science and Technology
Current assignee: Nanjing University of Science and Technology
Priority date: 2021-08-24
Filing date: 2021-08-24
Publication date: 2021-11-12

Abstract

The invention provides a target tracking method, which comprises the following steps: the radar transmits a group of tracking beams to track the target, and the radar does not transmit search beams at the pointing angle of the tracking beams; predicting the pointing angle of the tracking beam at the next moment according to the speed, distance and angle information of the target at the previous moment; the pointing angle of each group of tracking beams at least comprises an angle corresponding to the target position predicted at the last moment, and an upper part and a lower part of the angle. The target tracking method provided by the invention is accurate and energy-saving.

Description

Target tracking method

Technical Field

The invention relates to a target tracking technology, in particular to a target tracking method.

Background

The traditional mechanical scanning radar does not have the advantage of flexible resource allocation of a phased array radar, and can not switch the beam to detect the direction pointed by the beam at any time according to the information of the target at the moment, so when tracking the target, a Track While Searching (TWS) technology is generally adopted, and the technology refers to performing data processing such as association, filtering and the like on each frame of data obtained by searching to realize the tracking of the target. The phased array radar has the performance of flexibly distributing radar resources, and the wave beam can point to any position at any time without inertia, so that when a target is tracked, a Search and tracking (TAS: Track and Search) technology can be adopted, a Search task and a tracking task of the radar are divided into two relatively independent processes in time in the mode, and the tracking wave beam and the Search wave beam are reasonably arranged in a time alternation mode. However, TAS is a very radar time resource consuming operation, and each target needs to schedule a different beam for tracking.

Disclosure of Invention

The invention aims to provide an accurate and energy-saving target tracking method.

In order to achieve the above object, the present invention provides a target tracking method, including:

the radar transmits a group of tracking beams to track the target, and the radar does not transmit search beams at the pointing angle of the tracking beams; predicting the pointing angle of the tracking beam at the next moment according to the speed, distance and angle information of the target at the previous moment; the pointing angle of each group of tracking beams at least comprises an angle corresponding to the target position predicted at the last moment, and an upper part and a lower part of the angle.

Further, the pointing angle of each group of tracking beams further includes the left side and the right side of the angle corresponding to the target position predicted at the previous time.

Further, the range and the number of the radar transmitting the tracking beam to the space domain at a certain time are respectively as follows: transmitting 13 wave beams with pointing angles within the range of an azimuth angle of +/-45 degrees, and setting 11 wave beams with pointing angles within the range of a pitch angle of 0-45 degrees; the range of the tracking beam minus the pointing angle at which the instant overlaps the tracking beam pointing angle.

Further, the method comprises the steps that the radar determines a searched target before transmitting the tracking beams, and the determination method comprises the steps of continuously transmitting two beams of search beams; the condition that the target is judged to be searched is that the target speed is greater than the threshold value, and the condition that the target is confirmed is that the target speed obtained by one confirmed beam is greater than the threshold value.

Further, if the target tracking fails, the radar transmits a search beam at the pointing angle of the tracking beam.

Further, the determination condition of the target tracking failure is that the target is not tracked at three consecutive times.

Compared with the prior art, the invention has the following advantages: (1) the search is dominant, so that the search of the airspace where the tracking beam is positioned is reduced, and the time cost is saved; (2) when a certain pointing angle is in a tracking mode, the pointing angle does not transmit a search beam any more, so that interference of echo data is avoided, and tracking with higher data rate can be realized.

The invention is further described below with reference to the accompanying drawings.

Drawings

FIG. 1 is a schematic flow chart of the method of the present invention.

Detailed Description

With reference to fig. 1, the present embodiment relates to a target tracking method, when a radar transmits a tracking beam to track a target, the radar does not transmit a search beam at a pointing angle of the tracking beam. Specifically, the process of finding and tracking a target by a radar comprises the following steps:

s100, searching an airspace by a radar transmitting search wave beam;

step S200, confirming the searched target;

and step S300, the radar transmits a tracking beam to track the target.

In step S100, a radar transmits a search beam to search an airspace, and the specific search method includes: the coverage range of the search strategy comprises an azimuth angle of +/-45 degrees and a pitch angle of 0-45 degrees, 13 wave beams with pointing angles are arranged in the range of the azimuth angle, and 11 wave beams with pointing angles are arranged in the range of the pitch angle; 143 wave beams are arranged in one period, namely, the wave beams in 13 directions are sequentially transmitted to 11 wave beams in elevation directions, each frame of data of the echo is processed, and position information such as speed, distance, angle and the like of each search wave beam detection target is obtained.

Step S200 specifically includes the following steps:

step S201, judging whether the tracking condition is met or not according to the speed information obtained by calculation in step S100, and if the tracking condition is not met, turning to step S100 to scan; if yes, go to step S202;

step S202, the target emission confirmation wave beam is confirmed.

Preferably, the speed satisfying the tracking condition in step S201 of the present embodiment is greater than 50 m/S.

Further, in step S202, the beam is confirmed to be the tracking beam of the target meeting the tracking condition in step S201. And confirming the target by the confirmation beam according to whether the speed information in the echo data meets the speed size. Preferably, in step S202, two confirmation beams are continuously transmitted, that is, two beams with the same pointing angle are continuously irradiated to confirm the target, and as long as any one of the two confirmation beams can confirm the target, the target confirmation is successful.

In step S300, a group of tracking beams is emitted every certain period, and the position of the target at the next moment is predicted according to the tracking beams, which includes the following steps:

step S301, obtaining position information such as target speed, distance, angle and the like according to echo data at the last moment;

step S302, predicting the position information of the target at the next moment according to the position information of the target such as speed, distance, angle and the like, and further obtaining the pointing angle of the tracking beam.

Further, in step S301, the echo data at the previous time may be echo data of a search beam or echo data of a tracking beam; the period in this embodiment is 200 ms.

Further, in step S302, since the target flies along the parabolic track, the moving track of the target can be predicted according to the target speed, distance, pitch angle, and azimuth information.

Preferably, in step S302, the transmitted group of tracking beams includes three beams, and the pointing angles of the three beams are respectively the pointing angle corresponding to the predicted position information of the target at the next time, and above and below the pointing angle. The three tracking beams are arranged in a group, so that the target flies in a parabolic track after being taken out of the chamber, the fluctuation of the target pitch angle is considered, the three tracking beams just correspond to the predicted target position at the next moment, and the positions above and below the target position, and the target cannot be tracked due to the fluctuation of the pitch angle. Considering the fluctuation of the target in azimuth, a group of tracking beams may be set to five, and on the basis of three tracking beams, corresponding tracking beams are transmitted on the left and right sides of the predicted position of the advancing direction of the target.

When the step S300 is executed, the radar does not transmit the search beam at the pointing angle corresponding to the predicted target position information, that is, the number of beams arranged in one period is less than 143; likewise, at the remaining pointing angles, the radar does not emit a tracking beam. The step S300 aims to reduce the search of the airspace where the tracking wave beam is positioned when the airspace is searched, so that the time cost is saved; when the target is tracked, the echo data of the search beam does not interfere with the echo data of the tracking beam, and the tracking with higher data rate can be realized.

After step S300, if the target tracking fails, the target is abandoned from continuing to transmit the tracking beam, and step S100 is performed to continue to transmit the search beam to the pointing angle. The condition for determining the target tracking failure in step S400 is: and if the predicted position information of the next moment is not tracked to the target, and the predicted position information of the last two moments is not tracked to the target, the target is lost.

Claims

1. A target tracking method, comprising:

the radar transmits a group of tracking beams to track the target, and the radar does not transmit search beams at the pointing angle of the tracking beams; wherein

Predicting the pointing angle of the tracking beam at the next moment according to the speed, distance and angle information of the target at the previous moment;

the pointing angle of each group of tracking beams at least comprises an angle corresponding to the target position predicted at the last moment, and an upper part and a lower part of the angle.

2. The method of claim 1, wherein the pointing angle of each tracking beam set further comprises a left side and a right side of the predicted target position at the previous time.

3. The method of claim 1 or 2, wherein the radar transmits the tracking beams in the spatial domain in a range and number of the tracking beams at a time respectively:

13 directional angle beams are transmitted in the azimuth angle range of +/-45 degrees,

setting 11 wave beams with pointing angles in a pitch angle range of 0-45 degrees;

the range of the tracking beam minus the pointing angle at which the instant overlaps the tracking beam pointing angle.

4. The method of claim 3, further comprising the step of determining the searched target by the radar before transmitting the tracking beams, wherein the determination method comprises the steps of continuously transmitting two searching beams; the condition that the target is judged to be searched is that the target speed is greater than the threshold value, and the condition that the target is confirmed is that the target speed obtained by one confirmed beam is greater than the threshold value.

5. The method of claim 4, wherein if the target tracking fails, the radar transmits a search beam at the pointing angle of the tracking beam.

6. The method according to claim 5, wherein the determination condition that the target tracking fails is that the target is not tracked at three consecutive times.