本文選題：耦合光孤子　切入點：相互作用　出處：《聊城大學》2017年碩士論文

【摘要】：在光通信系統(tǒng)中,孤子通信具有著它獨特的魅力。特別是在高速通信中,其利用色散與非線性效應相互平衡的方法,使得非線性效應對系統(tǒng)性能的不良影響大大降低。另外,光孤子通信還具有中繼距離長,誤碼率低,節(jié)約中繼成本等特點�，F(xiàn)代光通信系統(tǒng)正在向著高速率、大容量、長距離的方向發(fā)展,光脈沖的寬度早已經(jīng)提高到了飛秒量級,隨著信號頻率的逐漸增加,其中涉及的非線性和色散效應也越來越復雜,所以利用飛秒光孤子通信來克服這種問題具有迫切的現(xiàn)實意義。在高速光通信系統(tǒng)中,為了提高通信速率,脈沖之間距離也要隨之壓縮,這會引起通信系統(tǒng)中光脈沖間的相互作用問題。耦合飛秒光孤子通信是集多路復用和孤子傳輸為一體的現(xiàn)代通信技術。在同一根光纖中傳輸多路信號時也會引起相互干擾的問題,對通信造成嚴重影響。本文利用基于符號計算的雙線性法,對不同高速通信系統(tǒng)中的光孤子進行解析求解,并對孤子間的相互作用進行分析。具體完成工作如下:1.在波分復用(WDM)系統(tǒng)中,利用多種不同波長的載波來傳遞信號,并最終耦合到同一根光纖中進行傳輸,實現(xiàn)了傳輸容量的倍增。但是在WDM系統(tǒng)中不同波長脈沖之間的相互干擾,一直是提高復用效率的難點。本文將利用孤子傳輸來克服不同波長信號間的相互干擾問題,同時對每一路信號中脈沖間的相互作用進行研究。在高速WDM系統(tǒng)中,孤子脈沖的傳輸模型為N路耦合高階非線性薛定諤方程(N-CHNLSE)。我們將利用雙線性方法對N-CHNLSE模型進行孤子求解,對每一路的傳輸狀態(tài)進行觀察,并通過改變其中一路孤子脈沖的傳輸狀態(tài),對產(chǎn)生的相互作用進行研究。2.在雙折射光纖中,脈沖傳播時會形成x和y兩個方向的偏振態(tài),科學家們利用這種特性可以實現(xiàn)偏振復用來提高通信容量。而光脈沖以孤子的形式傳播時,可以可以克服普通光脈沖無法保持恒定的偏振態(tài)的困擾。在雙折射光纖中,孤子脈沖不僅可以保持強度和波形不變,還能實現(xiàn)偏振態(tài)穩(wěn)定傳輸?shù)男Ч�。本文將對雙折射光纖中的高維飛秒耦合亮孤子和暗孤子進行探索,研究的模型為(3+1)維耦合高階非線性薛定諤方程。我們將利用雙線性方法對模型求亮、暗孤子解,在不同平面上觀察孤子的傳輸演化情況,并改變孤子的狀態(tài),對孤子間的相互作用進行研究。并且,經(jīng)過退化得到了(2+1)維耦合飛秒光孤子。3.在耦合飛秒光脈沖滿足的傳輸模型的基礎上,本文將對最近幾年在光學領域發(fā)現(xiàn)的另一種特殊波形“光怪波”進行探索。通過對傳輸模型的拓展,本文利用雙線性法得到了多維的耦合飛秒呼吸子和光怪波,并分析了它們在長度、寬度、峰值等方面的特性,發(fā)現(xiàn)了光學怪波在通信系統(tǒng)中同樣擁有著極其重要的應用價值。
[Abstract]:In optical communication system, soliton communication has its unique charm.Especially in high speed communication, the negative effect of nonlinear effect on system performance is greatly reduced by using the method of mutual balance between dispersion and nonlinear effect.In addition, soliton communication has the advantages of long relay distance, low bit error rate and low relay cost.The modern optical communication system is developing towards the direction of high speed, large capacity and long distance. The width of optical pulse has been increased to the order of femtosecond, and with the increasing of signal frequency,The nonlinear and dispersion effects involved are becoming more and more complicated, so it is of urgent practical significance to use femtosecond optical soliton communication to overcome this problem.In high speed optical communication system, in order to improve the communication rate, the distance between pulses must be compressed, which will cause the interaction between optical pulses in the communication system.Coupled femtosecond optical soliton communication is a modern communication technology which integrates multiplexing and soliton transmission.The transmission of multichannel signals in the same optical fiber will also cause the problem of mutual interference, which will seriously affect the communication.In this paper, a bilinear method based on symbolic computation is used to solve the solitons in different high-speed communication systems, and the interaction between solitons is analyzed.The details of the work are as follows: 1.In wavelength division multiplexing (WDM) WDM) system, a variety of carriers with different wavelengths are used to transmit signals, which are finally coupled to the same optical fiber for transmission, so that the transmission capacity is doubled.However, the interference between different wavelength pulses in WDM system is always difficult to improve the efficiency of multiplexing.In this paper, soliton transmission is used to overcome the problem of interference between different wavelength signals, and the interaction between pulses in each signal is studied at the same time.In a high-speed WDM system, the transmission model of soliton pulses is N-channel coupled higher-order nonlinear Schrodinger equation (N-CHNLSEE).We will use the bilinear method to solve the soliton of N-CHNLSE model, observe the transmission state of each channel, and study the interaction by changing the transmission state of one of the soliton pulses.In birefringent fiber, the polarization states in x and y directions can be formed when the pulse propagates, which can be used by scientists to realize polarization multiplexing to improve the communication capacity.When the optical pulse propagates as a soliton, it can overcome the problem that ordinary optical pulse can not maintain a constant polarization state.In birefringent fiber, the soliton pulse can not only keep the intensity and waveform unchanged, but also realize the effect of stable transmission in the polarization state.In this paper, the high-dimensional femtosecond coupled bright solitons and dark solitons in birefringent optical fiber are investigated. The model is the high-order nonlinear Schrodinger equation.We will use the bilinear method to obtain the bright and dark soliton solutions of the model, observe the propagation evolution of the soliton on different planes, change the state of the soliton, and study the interaction between solitons.Furthermore, we have obtained the femtosecond soliton. 3.Based on the transmission model of coupled femtosecond optical pulses, this paper will explore another special wave "light strange wave" which has been discovered in the field of optics in recent years.By extending the transmission model, the multi-dimensional coupled femtosecond respitons and optical strange waves are obtained by bilinear method, and their characteristics in length, width and peak value are analyzed.It is found that optical strange waves also have very important application value in communication system.
【學位授予單位】：聊城大學
【學位級別】：碩士
【學位授予年份】：2017
【分類號】：TN929.1

【參考文獻】

相關期刊論文 前3條

1 蔡躍進;白成林;羅清龍;;Exact Soliton Solutions for the (2+1)-Dimensional Coupled Higher-Order Nonlinear Schr¨odinger Equations in Birefringent Optical-Fiber Communication[J];Communications in Theoretical Physics;2017年03期

2 ;Some Special Types of Solitary Wave Solutions for (3+1)-Dimensional Jimbo-Miwa Equation[J];Communications in Theoretical Physics;2004年06期

3 ;New Explicit Exact Solutions for the(2+1)-Dimensional Higher-Order Broer-Kaup System[J];Communications in Theoretical Physics;2004年04期

，

本文編號：1729346