本文選題：細胞神經(jīng)網(wǎng)絡(luò) + 超混沌�。� 參考：《哈爾濱工業(yè)大學(xué)》2015年碩士論文

【摘要】：CNN(Cellular Neural Network,細胞神經(jīng)網(wǎng)絡(luò))是基于Hopfield神經(jīng)網(wǎng)絡(luò)和細胞自動機提出的一種反饋型神經(jīng)網(wǎng)絡(luò)。CNN具有多個可供設(shè)置的參數(shù)且當CNN的參數(shù)設(shè)置滿足一定的條件時,就會產(chǎn)生混沌及超混沌現(xiàn)象。CNN超混沌系統(tǒng)具有初值敏感性,由CNN超混沌系統(tǒng)生成的超混沌擴頻序列具有良好的偽隨機特性,能夠代替?zhèn)鹘y(tǒng)擴頻序列應(yīng)用于CDMA(Code Division Multiple Access,碼分多址)系統(tǒng)中。此外,CNN優(yōu)良的并行信號處理能力也可以用來解決CDMA系統(tǒng)的多用戶檢測問題。目前,空間多目標測控系統(tǒng)在通信與數(shù)據(jù)傳輸層面多采用CDMA體制,即用不同的擴頻序列來區(qū)分不同的衛(wèi)星。因此,對CNN超混沌系統(tǒng)的研究完全可以應(yīng)用于空間多目標測控系統(tǒng)中。本文針對CNN超混沌特性開展理論和應(yīng)用研究具有重要意義。本文首先對CNN超混沌系統(tǒng)的動力學(xué)特性展開研究,建立CNN全互連拓撲結(jié)構(gòu)及狀態(tài)方程,分析CNN超混沌系統(tǒng)的初值敏感性、有界性和遍歷性、Lyapunov指數(shù)、奇怪吸引子等特性,并基于上述特性,提出了CNN超混沌系統(tǒng)判定及篩選算法,該算法可以從大量的CNN中篩選出能夠產(chǎn)生超混沌現(xiàn)象的CNN系統(tǒng),這為以后的研究工作奠定了基礎(chǔ)。然后本文對CNN超混沌擴頻序列的生成、量化及篩選展開了研究。通過對超混沌擴頻序列的性能進行分析,提出了CNN超混沌擴頻序列篩選算法,以篩選出具有良好特性的超混沌擴頻序列。將篩選出的CNN超混沌擴頻序列應(yīng)用于CDMA系統(tǒng)之中,可提高系統(tǒng)的容量、誤碼性能和保密性能。然后本文對CDMA系統(tǒng)中的多用戶檢測問題展開了研究。首先分析了幾種常見的多用戶檢測算法,然后結(jié)合最優(yōu)多用戶檢測算法和CNN的Lyapunov函數(shù),提出了CNN多用戶檢測算法,并針對其容易陷入Lyapunov函數(shù)局部極小點的問題進行了簡化降階。簡化的CNN多用戶檢測算法能夠快速有效地減弱用戶間的多址干擾。最后,本文研究了CNN超混沌系統(tǒng)在空間多目標測控系統(tǒng)通信與數(shù)據(jù)傳輸層面的應(yīng)用。通過搭建空間多目標測控系統(tǒng)的通信與數(shù)據(jù)傳輸模型,設(shè)計具體通信方案,將篩選出的CNN超混沌擴頻序列及簡化的CNN多用戶檢測算法應(yīng)用于空間多目標測控系統(tǒng)的收發(fā)兩端,使系統(tǒng)獲得了良好的性能。
[Abstract]:CNN(Cellular Neural Network (CNN) is a feedback neural network based on Hopfield neural network and cellular automata.The chaotic and hyperchaotic systems are sensitive to initial values, and the hyperchaotic spread spectrum sequences generated by CNN hyperchaotic systems have good pseudorandom characteristics.It can be used in CDMA(Code Division Multiple access (CDMA) system instead of traditional spread spectrum sequence.In addition, the excellent parallel signal processing ability of CDMA can also be used to solve the problem of multiuser detection in CDMA system.At present, CDMA system is widely used in the communication and data transmission of space multi-target TT & C system, that is, different spread spectrum sequences are used to distinguish different satellites.Therefore, the study of CNN hyperchaotic system can be applied to space multi-target measurement and control system.In this paper, it is of great significance to study the hyperchaos characteristics of CNN in theory and application.In this paper, the dynamical characteristics of CNN hyperchaotic system are studied, and the topological structure and state equation of CNN complete interconnection are established. The initial value sensitivity, boundedness and ergodicity of CNN hyperchaotic system are analyzed.Based on the above characteristics, a CNN hyperchaotic system decision and screening algorithm is proposed. The algorithm can screen out the hyperchaotic CNN system from a large number of CNN, which lays a foundation for future research.Then, the generation, quantization and screening of CNN hyperchaotic spread spectrum sequences are studied.Based on the analysis of the performance of the hyperchaotic spread spectrum sequence, the CNN hyperchaotic spread spectrum sequence screening algorithm is proposed to screen the hyperchaotic spread spectrum sequence with good characteristics.The CNN hyperchaotic spread spectrum sequence is applied to the CDMA system, which can improve the capacity, error performance and security performance of the system.Then, the problem of multi-user detection in CDMA system is studied in this paper.In this paper, several common multiuser detection algorithms are analyzed, and then the CNN multiuser detection algorithm is proposed by combining the optimal multiuser detection algorithm with the Lyapunov function of CNN, and the order reduction of the CNN multiuser detection algorithm is simplified to the problem that it is easy to fall into the local minima of Lyapunov function.The simplified CNN multiuser detection algorithm can reduce the multiple access interference between users quickly and effectively.Finally, this paper studies the application of CNN hyperchaotic system in the communication and data transmission of space multi-target measurement and control system.By building the communication and data transmission model of the spatial multi-target measurement and control system, the specific communication scheme is designed. The selected CNN hyperchaotic spread spectrum sequence and the simplified CNN multi-user detection algorithm are applied to the two ends of the spatial multi-target measurement and control system.The system has achieved good performance.
【學(xué)位授予單位】：哈爾濱工業(yè)大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：V556;O415.5

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本文編號：1756405