Research On Evaluation Method Of Cooperative Jamming Effect In Complex Electromagnetic Environment

With the development of netted-radar technologies,The penetration process of target is vulnerable with various enemy search,tracking,and guidance radars.In the battlefield there are many different radar signal carrier frequency,pulse width,bandwidth and modulation to form a complex electromagnetic environment.In order to protect the target successfully,the cooperative jamming plays a very important role in the radar network.The evaluation of the cooperative interference effect,as an analysis of the combat capability of the netted radar with jamming,is an important indicator reflecting the penetration ability of the jammer,and is affected by many factors of the counter-parties.The rapid and reasonable evaluation methods are beneficial to the attacker to change the jamming strategy in time,which is of great significance.In this paper,the evaluation of the cooperative jamming effects and the allocation methods of the jamming resources under the complex electromagnetic environment are modelled.The improved genetic algorithm and particle swarm optimization are used to simulate and analyze the evaluation results.Firstly,aiming at the existence of pulse loss in the time domain in the complex electromagnetic environment,a new method based on intermittent sampling is proposed to superimpose and transmit the interference pattern.By controlling the superimposed parameters,this method can generate more flexible or longer-disturbed jamming or suppression effects;In the frequency domain,the single-unit jammer can't meet the defects of the jamming requirements due to the wide frequency spectrum is occupied by many radar signals,and the DRFM technology based cooperative power and time jamming methods is proposed.Through theoretical analysis and simulation comparison,the method is verified Effectiveness.Secondly,in the evaluation of jamming effectiveness,the calculation method of a number of factors in time domain,frequency domain,airspace and jamming mode under different jamming modes is analyzed,and the benefit matrix of impact factors is established.According to the radar signal processing process,using the detection probability and positioning accuracy of the netted radar as an evaluation index,and then a “weighted-sum of jammer effects on different distances” is proposed as an objective function of the evaluation for the cooperative jamming effects.Meanwhile,a cooperative jamming effect evaluation model is established.In addition,the effects of different jamming strategies on the interference of netted radar are analyzed,and the rationality and effectiveness of the model are verified.Finally,consider a scenario of that there are many radars and jammers against each other,the traditional traversing algorithm can't find the optimal allocation strategy of jamming system.The population intelligence optimization algorithm is applied to the allocation of cooperative jamming resources,and it is also applied to genetic algorithms and particle swarm optimization.For genetic algorithm and particle swarm optimization algorithm,there is the disadvantage of slow convergence speed and local convergence in the allocation of interference resources.The genetic algorithm and the particle swarm optimization algorithm are improved respectively.The improved algorithm is applied to the allocate the jamming resources and the evaluation of jamming effects.The improved algorithm has significant effects in improving convergence speed and avoiding local convergence after test.