【摘要】：近年來,隨著信息技術(shù)的快速發(fā)展,利用半導(dǎo)體激光器產(chǎn)生的混沌激光信號因其在高速保密通信、混沌雷達(dá)以及高速隨機(jī)數(shù)產(chǎn)生等方面的巨大應(yīng)用前景而成為人們關(guān)注的焦點(diǎn)。通常,半導(dǎo)體激光器在光反饋、光注入及光電反饋等外部擾動作用下可產(chǎn)生混沌信號。其中,通過引入光反饋產(chǎn)生的混沌信號會不可避免的保留一定的時間延遲特征(TDS),這不利于混沌激光信號在混沌保密通信及隨機(jī)數(shù)產(chǎn)生等領(lǐng)域的應(yīng)用。因此,有必要采用適當(dāng)方法對混沌信號的TDS進(jìn)行有效抑制。特別地,垂直腔面發(fā)射激光器(VCSELs)在適當(dāng)條件下可能同時存在兩個相互正交的偏振分量(X-PC,Y-PC),將三個及以上VCSELs構(gòu)成環(huán)形系統(tǒng),理論上可同時產(chǎn)生多路混沌激光信號。若將此系統(tǒng)作為混沌熵源,則具有同時產(chǎn)生多路隨機(jī)比特序列的可能性。本文提出了一種基于三個單向偏振旋轉(zhuǎn)耦合1550 nm-VCSELs構(gòu)成的環(huán)形系統(tǒng)獲取多路高質(zhì)量混沌信號的方案。利用自旋反轉(zhuǎn)模型,理論研究了該系統(tǒng)中三個激光器各偏振分量輸出信號的非線性動力學(xué)特性;采用自相關(guān)和互信息方法分析了各偏振分量輸出時間序列的TDS,并利用互相關(guān)函數(shù)討論了各偏振分量之間的相關(guān)特性。研究結(jié)果表明:采用偏振旋轉(zhuǎn)耦合的方式,通過合理調(diào)節(jié)各激光器之間的注入強(qiáng)度和頻率失諧,三個1550 nm-VCSELs的六個偏振分量能同時存在,且各偏振分量的輸出功率相當(dāng);系統(tǒng)中單向偏振旋轉(zhuǎn)耦合的注入強(qiáng)度和頻率失諧對該系統(tǒng)輸出的六路信號的TDS均有顯著影響;對于分別固定注入強(qiáng)度或頻率失諧的情況,通過調(diào)節(jié)其他系統(tǒng)參量可使各偏振分量輸出信號的TDS峰值均被抑制到0.2以下;通過綜合分析注入強(qiáng)度和頻率失諧聯(lián)合作用對系統(tǒng)輸出信號TDS的影響,確定了能有效抑制各路混沌信號TDS的耦合參數(shù)取值的精確范圍;通過進(jìn)一步優(yōu)化系統(tǒng)參數(shù)范圍,可保證六路輸出信號中僅同一個VCSEL輸出的兩偏振分量之間存在較強(qiáng)的相關(guān)性,而不同VCSELs偏振分量輸出信號之間的相關(guān)性均較弱。因此,該系統(tǒng)能同時輸出六路TDS被有效抑制的混沌信號,且其中三路混沌信號的相關(guān)性較弱。
[Abstract]:In recent years, with the rapid development of information technology, chaotic laser signals generated by semiconductor lasers have become the focus of attention due to their great application prospects in high speed secure communication, chaotic radar and high speed random number generation. Generally, semiconductor lasers can produce chaotic signals under external disturbances such as optical feedback, optical injection and optoelectronic feedback. Among them, the chaotic signal generated by optical feedback will inevitably retain a certain time delay characteristic (TDS), which is not conducive to the application of chaotic laser signal in the field of chaotic secure communication and random number generation. Therefore, it is necessary to effectively suppress the TDS of chaotic signals by appropriate methods. In particular, the vertical cavity surface emitting laser (VCSELs) may have two orthogonal polarization components (X-PC-Y-PC) at the same time under appropriate conditions. Three or more VCSELs are used to form a ring system. In theory, multiple chaotic laser signals can be generated at the same time. If the system is used as a chaotic entropy source, it is possible to produce multiple random bit sequences at the same time. In this paper, a scheme for obtaining high quality chaotic signals from a ring system based on three unidirectional polarization rotation coupling 1550 nm-VCSELs is proposed. Based on the spin inversion model, the nonlinear dynamic characteristics of the output signals of three laser polarization components in the system are studied theoretically. The autocorrelation and mutual information methods are used to analyze the TDS, of each polarization component output time series and the correlation characteristics between the polarization components are discussed by using the cross-correlation function. The results show that the six polarization components of three 1550 nm-VCSELs can exist at the same time by adjusting the injection intensity and frequency detuning between the lasers by polarization rotation coupling, and the output power of each polarization component is equal. In the system, the injection intensity and frequency detuning of the unidirectional polarization rotation coupling have a significant effect on the TDS of the six-channel signal output by the system. In the case of fixed injection intensity or frequency detuning, the TDS peak of each polarization component output signal can be restrained below 0.2 by adjusting other system parameters. By synthetically analyzing the influence of the combination of injection intensity and frequency detuning on the output signal TDS of the system, the precise range of coupling parameters of the TDS which can effectively suppress the chaotic signals is determined. By further optimizing the parameter range of the system, it can be ensured that there is a strong correlation between the two polarization components of only one VCSEL output signal in the six-channel output signal, but the correlation between the output signals of different VCSELs polarization components is weaker. Therefore, the system can output six chaotic signals effectively suppressed by TDS at the same time, and the correlation of three chaotic signals is weak.
【學(xué)位授予單位】：西南大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2017
【分類號】：TN248

【參考文獻(xiàn)】

相關(guān)期刊論文 前7條

1 楊欣;陳建軍;吳正茂;夏光瓊;黃守文;鄧濤;;光電負(fù)反饋下1550nm垂直腔表面發(fā)射激光器的動力學(xué)特性[J];光子學(xué)報;2016年08期

2 魏麗霞;唐曦;吳正茂;夏光瓊;;基于雙光反饋垂直腔面發(fā)射激光器獲取雙路高速物理隨機(jī)數(shù)研究[J];光電子·激光;2015年11期

3 鄭安杰;吳正茂;鄧濤;李小堅;夏光瓊;;偏振保持光反饋下1550 nm垂直腔面發(fā)射激光器的非線性動力學(xué)特性研究[J];物理學(xué)報;2012年23期

4 顏森林;;外部光注入空間耦合半導(dǎo)體激光器高維混沌系統(tǒng)的增頻與控制研究[J];物理學(xué)報;2012年16期

5 王云才;;混沌激光的產(chǎn)生與應(yīng)用[J];激光與光電子學(xué)進(jìn)展;2009年04期

6 李孝峰,潘煒,羅斌,馬冬,趙崢,鄧果;Theoretical study on controlling nonlinear behaviors of a coupled-cavity VCSEL by external optical injection[J];Chinese Optics Letters;2004年05期

7 趙耿,鄭德玲,張亦舜;混沌學(xué)及混沌電子學(xué)的發(fā)展[J];原子能科學(xué)技術(shù);2002年03期

，

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