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961.
Haiyan Chen 《International Journal of Infrared and Millimeter Waves》2005,26(8):1141-1150
This paper addresses in the design of thin film filter for IR broadband integrated photonic amplifiers. A cascaded multilayer medium thin film filter structure is presented. This proposed filter consists of some different filtering unit cells with different central wavelength and bandwidth, and each cell can suppress certain peak gain at a specific wavelength. The intrinsical gain spectrum of amplifier is obtained by solving a set of rate and power propagation equations with finite difference time-domain(FDTD)-based overlapping integral-Runge Kutter(RK) method. The effect of transmittance spectrum of the proposed cascaded multilayer medium thin film filter on flattening gain is discussed. The transmission function of the cascaded multilayer medium thin film filter is obtained. Finally, a real device is fabricated, it is shown that the design is valid. 相似文献
962.
963.
964.
蕴涵格的滤子及同余关系 总被引:2,自引:0,他引:2
在蕴涵格中引和了蕴涵滤子的概念,讨论了蕴涵滤子的一些基本性质,并由此建立了由素蕴涵滤子决定的同余关系及其商蕴涵格,以便为Fuzz推理建立了严格的逻辑基础作些必要的准备。 相似文献
965.
A simple configuration is proposed to perform wavelength switching in actively mode-locked fiber ring lasers, in which a sampled fiber Bragg grating and a tunable optical filter are cascaded in the ring cavity to exactly select the operating wavelength. The switching of four wavelengths with a spacing of 1.6 nm is obtained. The experimental results demonstrate that this technique is reliable and convenient. 相似文献
966.
CONSTRUCTION OF COMPACTLY SUPPORTED BIVARIATE ORTHOGONAL WAVELETS BY UNIVARIATE ORTHOGONAL WAVELETS 总被引:4,自引:0,他引:4
After some permutation of conjugate quadrature filter, new conjugate quadrature filters can be derived. In terms of this permutation, an approach is developed for constructing compactly supported bivariate orthogonal wavelets from univariate orthogonal wavelets. Non-separable orthogonal wavelets can be achieved. To demonstrate this method, an example is given. 相似文献
967.
Ultrafast multi-wavelength routing by an active birefringent fiber loop filter/interleaver is proposed and demonstrated. In
the proposed active filter, the loop part consists of a birefringent optical fiber and a traveling-wave-type phase modulator.
Numerical simulation using Jones matrix analysis shows that the periodic transmission/reflection bands of the filter can be
switched by changing a phase difference between clockwise and counter clockwise components passing through the birefringent
fiber loop. Experimentally, we realize fast switching by controlling the applied voltage to the phase modulator, and 8-GHz
wavelength routing operation is achieved. 相似文献
968.
Wilhelm Stannat 《Applied Mathematics and Optimization》2005,52(1):39-71
Stability of the pathwise filter equation for a time-dependent signal process induced by a
d-dimensional stochastic differential equation and a linear observation is studied, using a
variational approach introduced in [16]. A lower bound for the rate of stability is identified
in terms of the mass-gap of a parabolic ground state transform associated with the generator of the
signal process and the square of the observation. The lower bound can be easily calculated a priori and
provides hints on how precisely to measure the signal in order to reach a certain rate of stability. Ergodicity
of the signal process is not needed. 相似文献
969.
时间尺度域匹配滤波器的设计与实现 总被引:3,自引:0,他引:3
根据地震褶积模型,设计并实现了应用于探地雷达回波信号检测的时间尺度域匹配滤波器,利用小波变换的时间定位性和尺度伸缩性,检测出雷达接收信号中单个反射子波的位置与强弱信息,利用已知的雷达发射子波模型还原回波信号,达到了滤除噪声、最佳接收的目的.通过用传统相关匹配滤波方法和本方法对探地雷达接收数据进行比较试验发现:当信噪比比较低时,传统方法已经不能准确地检测出雷达子波,而本方法仍能准确的检测出90%的雷达子波.这表明,本方法具有更好的子波检测和滤波性能. 相似文献
970.
Horst Herrlich 《Mathematical Logic Quarterly》2003,49(3):323-324
It is shown that in ZF set theory the axiom of choice holds iff every non empty topological space has a maximal closed filter. 相似文献