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1.
商朋见 《计算物理》1997,14(1):54-62
研究了关于自仿集上电荷分布的势论及有关分析性质。指出电荷分布、势及其Fourier变换的构造性质;明确给出了三分Cantor集上二项分布及其矩、Fourier变换、势的具体表达式;并给出一些数值结果。  相似文献   

2.
自由空间光学Comega多级互连网络特性研究   总被引:2,自引:2,他引:0  
李源  曹明翠 《光学学报》1996,16(11):585-1590
光学Comega网络是一种新颖的易于光学实现的多级光互连网络。本文对该网络结构及特性进行了详细分析,和到了网络的互连函数,并给出了它与Staran,Crossover,Omega,Banyan及基准等常见网络的拓扑等价证明。  相似文献   

3.
徐文兰 《物理》1992,21(2):85-88
木本简单介绍了准晶的概念和一维Fibonacci准晶的结构,研究了一维准昂链所特有的Cantor-like积分振动态密度.在准晶的振动本征态中,除了低频区的扩展态和禁带中的局域态外,还有一种以在周期及无序结构中都没有的临界态.文章还讨论了在准晶中引入掺杂和错位等无序后对准晶原子链振动的影响.以上的研究为一种人工准晶体─—准晶超晶格的振动研究提供了理想的模型.  相似文献   

4.
彩色、黑白CCD摄像机产品报道台湾敏通公司为了广泛推广CCD应用技术,加强海峡两岸的学术交流,该公司在拓展CCD摄像机业务的同时,于1992年10月1日在北京创刊由该公司主办的《敏通科技》杂志,并在海峡两岸同步发送(截止到目前为止已出版发行了9期),...  相似文献   

5.
提出了一种新型光电混合循环排序网络。排序网的互连级采用自由空间光学反-逆混洗(Comega)互连,比较交换节点列阵采用硅互补金属-氧化物-半导体-自由光效应器件(CMOS-SEED)光电混合集成电路来实现。由于反-逆混洗多级网络各互连级完全相同,该排序网络通过采用循环结构大大地简化系统所需的硬件。通过采用并行比较交换节点进一步提高了排序网络中比较操作的速度。  相似文献   

6.
一种使用线阵型CCD实现高精度二维位置测量的方法   总被引:12,自引:2,他引:10  
介绍了一种使用CCD测量位置的方法。与其它CCD位置测量系统不同,通过设计一个特殊的光学系统,实现了使用两个线阵型CCD进行高精度二维位置坐标测量。文中对该光学系统进行了误差分析,证实该方法具有很高的测量精度。该二维位置测量方法具有一些突出的优点:系统响应速度快,可以对动态目标进行测量;测量精度高;制造成本低。上述特点使它在工业制造领域内有着广阔的应用前景。  相似文献   

7.
王大勇  李育林 《光学学报》1994,14(12):312-1315
描述了一种基于电寻址空间调制器的二值化联合变换相关器,该系统主要包括阴极射线管耦合液晶光阀(CRT-LCLV)、CCD摄象机和COMPAQ386计算机,文中在理论分析的基础上给出了计算机模拟和初步的实验结果,表明该相关器具有良好的识别性能。  相似文献   

8.
CCD在光谱分析系统中的应用研究   总被引:15,自引:3,他引:12  
本文对利用CCD作传感器件进行光谱分析的方法进行了理论和实验研究。通过分析CCD的结构特点和光电特性,从理论上证明了利用CCD进行光谱分析的可行性,设计了一套适合线阵CCD的高速图像采集卡,建立了一套智能化光谱数据采集分析系统。该系统主要由光栅、CCD传感器及数据采集卡、计算机等部分组成。我们用高压汞灯作为标准光谱进行定标,得到了一个非常简单的计算光谱的数学公式。实验表明该系统具有较高的测量精度,特别适用于瞬态过程的光谱分析。  相似文献   

9.
CC榕树网络及其光学实现   总被引:1,自引:0,他引:1  
彭海峰  刘立人 《光学学报》1996,16(6):89-892
利用偏振分光棱镜及一维位相型空间光调制器,作者成功地实现了光学CC榕树网络,并给出任意输入输出对间的连接控制方式,它具肥能量损耗低,串扰小,结构紧凑及高通道密度等优点。  相似文献   

10.
一种频域基频提取新方法   总被引:3,自引:0,他引:3  
提出了一种基于二值侧抑制网络的频域基频提取方法。即利用二值侧抑制网络对语音的短时谱进行峰值提取,得到包括语音基频及其谐波的线谱,根据谐波间的距离平均值估算出基频.该算法在COSDIC数据库上进行了测试,并与自相关基频提取法和倒谱基频提取法进行了比较.实验数据表明,本算法具有更高的精度和更强的抗噪声性能.  相似文献   

11.
CompactOpticalOmegaNetwork¥WANGNing;YINYaoal;QIANJiajun;LIULiren(ShanghaiInstituteofOpticsandFineMechanics,AcademiaSinica,P.O...  相似文献   

12.
赖俊森  杨爱英  孙雨南 《光学学报》2012,32(11):1106004
基于异步延迟采样和人工神经网络统计学习提出了一种光通信性能监测方法。通过对高速光信号进行异步延迟采样,获得信号二维幅度直方图,然后提取其中特征参数并对人工神经网络进行训练,最后以人工神经网络的预测输出实现对光信号损伤的监测。构建10 Gb/s非归零码开关键控,40 Gb/s光学双二进制码和归零码差分移相键控光通信仿真系统,并对光信噪比、色散和偏振模色散损伤进行监测。仿真结果表明,所提方法对被监测光信号的速率、码型调制格式透明,可同时准确监测多种并存的传输损伤,损伤参数监测误差小于5%。该方法具有电域处理带宽要求低、采样机制简单的特点,适用于分布式在线光性能监测。  相似文献   

13.
Chen H  Chen M  Xie S  Zhou B 《Optics letters》2006,31(9):1187-1189
We propose and experimentally demonstrate a polarization shift keying label and a vestigial sideband carrier-suppressed return-to-zero payload scheme for a 43 Gbit/s all-optical label switching network. This scheme has a narrow channel bandwidth and a low penalty due to polarization mode dispersion impairments, which confirm it as a candidate technique for the next generation of optical networks.  相似文献   

14.
Abstract

A novel full duplex fiber wireless link providing alternative wired and 60-GHz wireless access is proposed based on a polarization orthogonal dual-tone optical millimeter-wave signal. In a hybrid optical network unit, the downlink optical signal can be decomposed as a single-sideband optical millimeter-wave signal (baseband optical signal) for wireless (wired) access by a polarization controller and polarization beam splitter. The uplink optical carrier abstracted from the downlink optical signal makes the hybrid optical network unit free from the optical source. The simulation results show that both downlinks and uplinks for either wired or wireless access can maintain quite good performance over 60 km of fiber.  相似文献   

15.
Complex sub-Doppler spectra can be simplified by the application of microwave modulated polarization spectroscopy (MMPS). This new laser spectroscopy technique is based on a combination of Doppler free laser polarization spectroscopy with microwave optical polarization spectroscopy (MOPS). The method has been used to label particular optical lines in the B2σ-X2σ spectrum of SrF.  相似文献   

16.
王斌泉  刘立人  王宁  彭海峰 《光学学报》1996,16(12):1757-1761
在光学多级互连网络的实现中,光学2×2开关的构造是至关重要的。本文介绍一种构成光寻址2×2光学开关的方法,该方法是在方解石晶体的双折射性质的基础上,利用普克尔斯只读光调制器(PROM)来控制入射光的偏振态,从而实现光寻址2×2光学开关,这种开关具有许多优点,并且可以在3-D方向堆栈集成。利用该开关可以很方便地实现3-D集成的蝶形互连网络  相似文献   

17.
4×4自由空间光开关结构及其矩阵分析   总被引:10,自引:5,他引:5  
罗风光  曹明翠  谢胡  周新军  罗志祥  徐军 《光学学报》2004,24(12):1677-1680
光开关是全光通信网络中的一种重要的光无源器件。提出了一种4×4自由空间光开关的结构设计方法,并进行了矩阵理论分析。该4×4光开关具有新颖的光模块化结构,该光开关结构仅由偏振分束组合棱镜,λ/4波片,λ/2波片,直角棱镜,全反镜和偏振光调制器组成,对光开关的控制与输入光束的偏振态无关。所有的输出端口可以和输入端口无阻塞地互连交换。这种新型的光开关结构具有光学元件少,结构紧凑,模块化,与偏振无关的特点。基于4×4光开关的矩阵分析得到了路由控制表,为4×4光开关从任意输人端口到任意输出端口的路由控制状态提供了理论分析手段,从而可以方便地实现无阻塞地光交换开关矩阵的路由控制功能。  相似文献   

18.
Cameron J  Chen L  Bao X 《Optics letters》2000,25(12):884-886
We present analytical and experimental results to demonstrate the narrowing of pulses transmitted through optical fibers, with polarization mode dispersion compensated for to first order in frequency. The compensation technique splits the optical signal at the fiber output into polarization components that are aligned with the output principal states of polarization, and only one of the two components is subsequently detected. It is shown that it is possible with this compensation technique to have output pulses that are narrower than the input pulses. Pulse narrowing can also be found when the optical signal is split into orthogonal polarization components that are not principal states of polarization.  相似文献   

19.
An integrated optical coherent receiver with continuous state of polarization control is proposed and analyzed. The receiver consists of an integrated optical polarization rotator, a state of polarization detector and a balanced mixer receiver. Continuous state of polarization control can be achieved by using two polarization rotators in series and feeding the polarization rotator outputs into the state of polarization detector whose subsequent output is used to control the voltage settings on the polarization rotator. For the general case, the polarization rotator is comprised of two phase shifters and a TE - TM mode converter. The state of polarization detector stage consists of a δβ directional coupler mode splitter. A novel fabrication technique for achieving efficient polarization splitting is discussed. A balanced mixer receiver is implemented using a passive directional coupler with 50/50 power splitting. The need for a passive device is demonstrated and a method for achieving accurate power splitting ratios using the proton exchange fabrication technique is discussed and experimentally demonstrated. An analysis of the performance of such a system including the balanced mixer receiver is carried out to identify the critical areas of fabrication. Discussion is also given to the function and characteristics of the electronic control loop.  相似文献   

20.
CC-Banyan network plays an important role in the optical interconnection network. Based on previous reports of (2, 2, 3) the CC-Banyan network, another rectangular-Banyan network, i.e. (3, 3, 2) rectangular CC-Banyan network, has been discussed. First, according to its construction principle, the topological graph and the routing rule of (3, 3, 2) rectangular CC-Banyan network have been proposed. Then, the optically experimental setup of (3, 3, 2) rectangular CC-Banyan network has been designed and achieved. Each stage of node switch consists of phase spatial light modulator (PSLM) and polarizing beam-splitter (PBS), and fiber has been used to perform connection between adjacent stages. PBS features that s-component (perpendicular to the incident plane) of the incident light beam is reflected, and p-component (parallel to the incident plane) passes through it. According to switching logic, under the control of external electrical signals, PSLM functions to control routing paths of the signal beams, i.e. the polarization of each optical signal is rotated or not rotated 90° by a programmable PSLM. Finally, the discussion and analysis show that the experimental setup designed here can realize many functions such as optical signal switch and permutation. It has advantages of large number of input/output-ports, compact in structure, and low energy loss. Hence, the experimental setup can be used in optical communication and optical information processing.  相似文献   

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