Weak Signal Detection Based On Chaotic Characteristics Of Sea Clutter

The detection of weak signals in sea clutter has been a hot and difficult issue for along time in the field of target detection on sea surface, which has significant meaningsfor military and civil use. Based on the chaos theory, this paper studies the embeddedreconstruction of the real measurement sea clutter data. The methods proposed candetect the weak signals under low signal-to-noise ratio (SNR) effectively, whichvalidate the chaos characteristics of the sea clutter. The main topic of this paper isdetecting weak signals in sea clutter using chaos theory, while other related problemssuch as the characteristics and study methods of chaos are investigated too. The properchaos model of sea clutter is constructed to make better detection of weak signals. Themain works of the paper are as follows:1 The basic knowledge of chaos, the background, research meaning and the currentresearch introduction are briefly described in chapter 1.2 Firstly, the datas of sea clutter are introduced in chapter 2, secondly, two kinds ofChaos means of identifications are stressly studied: complexity of subjects andrecurrence quantification analysis method(RQA). The law in Poincare section is simplydirectly perceived, but only is confined to review in one dimension or two dimensions;The power spectrum law images directly perceived, but can not effectively differentiateChaos and non-Chaos signal; RQA can effectively identify the period and the chaoticand the random, as well as can all the dynamics specific property.Thirdly, preferences of chaos are introduced.3. The objects, basic principles and performance analysis of chaos signalprocessing is in chapter 3. According to the general train of thought of alignmentanalysis of Chaos time. Firstly analysing each other the space heavily constructs theselection of middle two the important parameters algorithm. The dead time and inlaysinto the dimension, next the motive power department baseded on heavily to constructall the looks space, Chaos three important parameters of method calculation ofutilization statistics: Lyapunov's index, minute dimension and K's entropy.4. The methods of weak signal detection in sea clutter is proposed in chapter 4based on phase reconstruction. Analysed to based on three kinds of methods of classicsof faint signal detection of the nonlinearity of Chaos theory: the smallest space volumelaw,RBF's nerve cross-domain communication law and Duffing's inspection model. Putforward to based on each other faint draing of signal under the sea noise backgroundthat heavily constructs in the space. The experiment is verified methodsimplyeffectively, can be in - under the circumstances of 20db to the noise backgroundof sea the faint target signal tests.5. Chapter 5 summarizes the paper.