The Methods Research On Pulsed Doppler Radar Against The Jamming Of Airborne Towed Decoy

With the development of Electronic Warfare (EW) between surface-to-air missile and air strikes, towed decoy as a new type of interference has been the universal concern of developed countries, and has become an effective mean to fight against tracking radar and missile seeker. As the most effective means of self-defense way, towed decoy is playing more and more important role. The United States has equipped towed decoy to combat aircraft now, and used it in the actual war. The towed decoy greatly reduced the killing probability of anti-air missile, and the effect is remarkable. Nowadays, there is little countermeasures theory about towed decoy in our country, and we have not carried out any test about how to confront towed decoy by now, so it is very necessary for us to research the imperative technology and methods against towed decoy.This paper introduces towed decoy simply at first, and then represents the research situation of towed decoy in domestic and international. What's more, the paper also shows the main problems that still existing now. The main contents of the paper were made a simple explanation in following. In order to found out the effective countermeasures methods against towed decoy, the paper analyzes the working way of towed decoy and the selecting principle of main parameter.Secondly, the paper builds a system model of Pulse Doppler radar in order to provide a platform for the following simulation. The mathematics model of Pulse Doppler radar's main modules is set up and simulated. The mathematics model of Pulse Doppler radar's echo signal is also built and the model for clutter and receiver interior noise is set up in follows. Then the paper explains the methods how to get the information of target's velocity, distance and angle from echo signal.Thirdly, the paper discusses the characteristics of jamming signal when towed decoy working in forwarding mode. The method of Leading-Edge Track is proposed in order to fight against towed decoy, and the feasibility of the method is proved by computer simulation results. How to isolate the target echo pulse is the key to using Leading-Edge Track effectively, and the width of extracted target echo pulse determines the detecting distance of PD radar. At last, the paper discusses the characteristics of jamming signal when towed decoy working in forwarding noise mode. The method of Dicke-fix is proposed according to the characteristics of noise FM jamming. Dicke-fix can realize the thought of fight against towed decoy by improving the signal-to-noise ratio (S/J). The feasibility of the method is proved by computer simulation results in follows. Then the paper points out the shortcomings of Dicke-fix, and improving methods are suggested.