Research on the Properties of a Surface-Type Infrared Decoy and Effect of Multiple Launching

To study the properties of a new surface-type infrared decoy,the numerical dispersion model and the infrared radiance model of the plates are established. In addition,the temperature of a single plate was measured during combustion experiment,and the spatial position and infrared radiance of each plate are calculated in plate cloud by the two models respectively. Furthermore,the radar images of the plate cloud are simulated and analyzed in dependence of time and direction for single and multiple launching. The result shows that the surface-type infrared decoy can be a point source of interference when the missile is remote tracking. In the meanwhile,the plates cloud shelters the infrared characteristics of the plume and jets of aircraft when the missile is on IR imaging guidance mode. Moreover,With the analysis of the plate cloud dispersion at different intervals and the infrared radiation intensity in the case of different launching number,it can be concluded that a comfortable launching interval can maintain a continuous plate cloud,launching the decoys simultaneously increase the increment of the radiation intensity obviously,the multiple launching is an effective way to enhance the interference property of the decoy.

Impact of Tactical Parameters of Aircraft on Jamming Effectiveness of Surface-Source IR Decoy

As the platform for surface-source infrared decoys,the target aircraft is the aim of attacks in air-to-air combat.It can quickly and accurately evaluate the jamming effectiveness of the surface-source IR decoy in various states of motion is important for enhancing the security of the aircraft.This paper proposes a model of surface-source IR decoy,and compares and analyzes simulated and measured infrared images of diffusion.A system to assess the effectiveness of the jamming of the surface-source IR decoy,target aircraft,and infrared guided missile called“Trinity”is established.Simulations were conducted to assess the impact of flight height,flight speed,and the maneuvering of the target aircraft on the jamming effectiveness of the surface-source IR decoy.The results show that with an increase in flight height and speed,the jamming probability of a surface-source IR decoy first increases and then decreases,where evasive maneuvering by the target aircraft can effectively improve this probability.When the radius of the vertical snake maneuver was 125 m,that of the horizontal snake maneuver was 200 m,and the radius of the barrel roll maneuver was 250 m,the jamming probability of the surface-source IR decoy was relatively high.By comparing the simulation results with measured data,the study verified the accuracy of the proposed method.

Aerodynamic Characteristics Calculation and Diffusion Law Analysis of Rectangular-Chaff Clouds Under Airflow

To calculate the diffusion law of chaff cloud launched by aircraft,taking rectangular chaff as an example,the diffusion model of chaff cloud is established in this paper.Firstly,the coordinate systems of chaff are defined and the motion model of chaff is established.The motion model mainly includes chaff motion equation and rotation equation,which are obtained by combining the aerodynamic moment and aerodynamic damping.Then,the influence of multi-chaff aerodynamic interference on the movement of chaff is analyzed.Finally,considering the influence of overlap area between chaffs and chaff spacing on the aerodynamic coefficients,the multi-chaff motion model is obtained,and the simulation results are compared with the test results to verify the credibility of the model.

Reinforcement learning-based missile terminal guidance of maneuvering targets with decoys

In this paper,a missile terminal guidance law based on a new Deep Deterministic Policy Gradient(DDPG)algorithm is proposed to intercept a maneuvering target equipped with an infrared decoy.First,to deal with the issue that the missile cannot accurately distinguish the target from the decoy,the energy center method is employed to obtain the equivalent energy center(called virtual target)of the target and decoy,and the model for the missile and the virtual decoy is established.Then,an improved DDPG algorithm is proposed based on a trusted-search strategy,which significantly increases the train efficiency of the previous DDPG algorithm.Furthermore,combining the established model,the network obtained by the improved DDPG algorithm and the reward function,an intelligent missile terminal guidance scheme is proposed.Specifically,a heuristic reward function is designed for training and learning in combat scenarios.Finally,the effectiveness and robustness of the proposed guidance law are verified by Monte Carlo tests,and the simulation results obtained by the proposed scheme and other methods are compared to further demonstrate its superior performance.

Experimental and numerical study of chaff cloud kinetic performance under impact of high speed airflow

To solve the kinetic and diffusion problem of surface-type infrared decoy, multi-chaff kinetic models are established and chaff cloud holistic kinetic performance are analyzed under the impact of high speed airflow in this work. Chaffs rotate rapidly during the motion under the impact of high speed airflow. The rotation speed is correlated with lift, position of pressure center and aerodynamic damping. Computational Fluid Dynamics(CFD) is used to compute the aerodynamic coefficients of chaff. It is found that there exists serious aerodynamic interference which mainly relates to the overlapping area and distance among chaffs during the diffusion of chaff cloud. The chaff wind tunnel test and rocket sled experiment are carried out to verify the credibility of the models in this work. Then, the variation of chaff cloud expectation and extremum are analyzed to achieve the holistic kinetic and diffusing performance of chaff cloud. Simulation results demonstrate that the chaffs diffuse rapidly under the impact of high speed airflow and chaff cloud can be formed rapidly within 0.5 s. The shape of the chaff cloud is similar to cone that forms a certain angle with the horizontal plane and most chaffs focus on the second half.