Based On The Distributed Coherent Detection System Of The Radio Frequency Energy Accumulation Method Research For A Long Time

There are some disadvantages for phased array radar. For example, it has poor stealthy performance and is susceptible to be intercepted; the array layout is inflexible, which is unsuitable for being transported by or equipped with platform; The ability to detect stealthy target is limited; and so on. In contrast, distributed array RF detection system has favorable stealthy performance, and the array of it can be arranged more flexible, which can be transported by or equipped with platform suitable, it also has sufficient ability to detect stealthy target. In addition, the anti-jamming capability is stronger due to its higher degree of freedom, the performance of multi-target tracking is also improved compared with phased array radar. The advantages of distributed array RF detection system make up the defects of phased array radar, which promote it become the inevitable trend of next generation RF detection system.The ratio of single-pulse echo to noise(SNR) for distributed array RF detection system decreases compared with phased array radar, but the observation time-length on target rises from milliseconds up to seconds. If echo energy of this period could be integrated, not only can decreasing of SNR be compensated, but higher SNR can also be gained, which improves target detection performance. This problem is long term energy integration, which is the content of this thesis. We investigated the long term energy integration methods based on distributed array RF detection system, including coherent integration method, non-coherent integration method. Then a hybrid integration method and a long term coherent integration method based on kinematics equations are proposed respectively. The specific contents are as follows:Firstly, the basic concept and principle of distributed array RF detection system are investigated. Then, the features of signal diversity and spatial diversity based on this system are discussed, and also its basic performance is analyzed.Secondly, through the establishment of the signal model, we point out the reasons for the coherent integration methodological problems. And, we introduce traditional coherent integration methods, including Keystone transform algorithm and range migration compensation algorithm based on envelope interpolation as well as de-chriping algorithm and Wigner-Ville distribution integration algorithm.Thirdly, On the basis of these tradional coherent integration algorithms, a long term coherent integration method based on kinematics equations is proposed, whose basic principle is analyzed specificly then. After that the application method of it is provided. Finally, the error introduced by this algorithms is discussed.Fourthly, non-coherent accumulation method of Hough transform algorithm is investigated. We analyze its basic principle in detail, which followed by the simulation.Fifthly, there are energy accumulation problems for high resolution radar detecting uniformly accelerated rectilinear motion targets as well as oblique unique uniform rectilinear motion targets, according to this, we present a hybrid accumulation method which mixes coherent and non-coherent integration method. Then, its application method is introduced. Finally, the simulation show its effectiveness.