柱透镜的位相变换作用

基于薄透镜假定和傍轴近似,给出了包含标准圆柱透镜、椭圆柱透镜、抛物柱透镜、双曲柱透镜等二次柱面透镜的位相变换因子,说明柱透镜这类位相物体在衍射光场中的单向调制作用,同时结合菲涅耳衍射实例体现了这类单柱透镜在实现组合变形分数傅里叶系统中的基元特性、灵活性及实用性.

用位相变换函数导出傍轴条件下透镜的物像距公式和横向放大率公式

现代变换光学用空间频谱变换描述光学现象,而透镜等光学器件在光学系统中,起到位相变换作用。本文用透镜的位相变换函数导出了傍轴条件下透镜的物像距公式和横向放大率公式。

用透镜的位相变换函数推导组合透镜的基点

本文运用现代光学中的相因子判断法,用透镜的位相变换函数推导出组合透镜的主点、焦点。这对于将几何光学的教学溶于波动光学中有一定的启发。

傅里叶变换条纹位相分析技术中移频消去载频法对位相分析的影响

在理论上分析了傅里叶变换位相分析技术中的移频消去载频法,由于采样的离散化,不同的条纹周期对位相分析将产生不同的影响。利用计算机仿真,模拟了不同周期的条纹图以及形变条纹图,根据傅里叶变换频移法,获得了不同周期条纹图的位相分布及误差,同时与"减基准条纹法"获得的位相分布及误差进行比较,验证了不同条纹周期对位相分析产生的影响。以花瓶为目标物体,在实验中进一步验证了采样的离散化对位相分析带来的误差和影响。并且讨论了两种减弱这种误差的方法。

正交柱透镜的分数傅里叶变换特性

根据正交柱透镜满足的几何关系,计算得到了正交柱透镜的透过率函数。之后根据菲涅耳衍射公式和已推导得到的透过率函数,导出了单正交柱透镜对称系统和双正交柱透镜系统输出面的光场复振幅分布,并与分数傅里叶变换定义式比较,得到了实现分数傅里叶变换的系统结构参量;正交柱透镜具有的不同维度实现不同级次分数傅里叶变换的性态,在雷达、通信的信号传递,图像加密和生物医学等应用领域具有实用价值。

无衍射光束概念及在强激光技术中潜在应用的分析

对近年来引起广泛研究兴趣和热烈争议的无衍射光束和相关的物理概念、产生方法和传输特性，以及在强激光技术中应用的可能性等问题，作了详细的物理分析，以期引起讨论。

菲涅耳双棱镜实验的相因子分析

根据波前相因子判断法,推导出缝光源在不同位置经双棱镜所成的像。得出缝与双棱镜的棱脊严格平行时,两相干光源振幅相同,形成清晰干涉图样;当缝与棱脊不平行但位于同一平面时,缝像平行于缝,但两像振幅不同,一定条件下可形成不清晰的干涉图样;当缝不在同一平面内时,缝像仍平行于缝,但不能形成干涉。

Amplitude spectrum compensation and phase spectrum correction of seismic data based on the generalized S transform

We propose a method for the compensation and phase correction of the amplitude spectrum based on the generalized S transform. The compensation of the amplitude spectrum within a reliable frequency range of the seismic record is performed in the S domain to restore the amplitude spectrum of reflection. We use spectral simulation methods to fit the time-dependent amplitude spectrum and compensate for the amplitude attenuation owing to absorption. We use phase scanning to select the time-, space-, and frequencydependent phases correction based on the parsimony criterion and eliminate the residual phase effect of the wavelet in the S domain. The method does not directly calculate the Q value; thus, it can be applied to the case of variable Q. The comparison of the theory model and field data verify that the proposed method can recover the amplitude spectrum of the strata reflectivity, while eliminating the effect of the residual phase of the wavelet. Thus, the wavelet approaches the zero-phase wavelet and, the seismic resolution is improved.

左手性媒质的等效电路

具有介电常数和负电导率的左手材料引起人们的广泛注意.负折射媒质有许多特殊的性质.等效的负折射媒质电路可以有效减小器件的尺寸,拓宽频带,改善器件的性能.本文从理论上讨论了微波电路中的三种负折射等效电路实现负折射的原理,对其相移常数进行了比较,并从相位和能量的角度对等效负折射电路的条件进行了分析.

透镜性质的探索

本文考虑到透镜对入射光波位相的影响,并通过计算得到球面波通过透镜后在紧接透镜的平面上的复振幅分布公式。

Comparison of signal reconstruction under different transforms

A newalgorithm, called Magnitude Cut, to recover a signal from its phase in the transform domain, is proposed.First, the recovery problem is converted to an equivalent convex optimization problem, and then it is solved by the block coordinate descent（ BCD） algorithm and the interior point algorithm. Finally, the one-dimensional and twodimensional signal reconstructions are implemented and the reconstruction results under the Fourier transform with a Gaussian random mask（ FTGM）, the Cauchy wavelets transform（ CWT）, the Fourier transform with a binary random mask（ FTBM） and the Gaussian random transform（ GRT） are also comparatively analyzed. The analysis results reveal that the M agnitude Cut method can reconstruct the original signal with the phase information of different transforms; and it needs less phase information to recover the signal from the phase of the FTGM or GRT than that of FTBM or CWT under the same reconstruction error.

Quantum Fourier Transform and Phase Estimation in Qudit System

The quantum Fourier transform and quantum phase estimation are the key components for many quantum algorithms, such as order-finding, factoring, and etc. In this article, the general procedure of quantum Fourier transform and phase estimation are investigated for high dimensional case run in a qudit quantum computer, and the quantum circuits are They can be seen as subroutines in a main program given.

Spatially Periodic System with Infinite Globally Coupled Oscillators Driven by Temporal-Spatial Noise

In this paper, we study spatially periodic system with infinite globally coupled oscillators driven by temporal-spatial noise and subject to a constant force. The results show that the system exhibits the phenomena of the non-equilibrium phase transition, transport of particles, and the anomalous hysteresis cycle for the mean field and the probability current.

MP-WFRFT and Constellation Scrambling Based Physical Layer Security System

In this paper, a multiple parameters weighted fractional Fourier transform(MPWFRFT) and constellation scrambling(CS) method based physical layer(PHY) security system is proposed. The proposed scheme is executed by two steps. In the first step, MPWFRFT, implemented as the constellation beguiling(CB) method, is applied to change the signal's identity. In the second step the additional pseudo random phase information, regarded as the encryption key, is attached to the original signal to enhance the security. Typically, the pseudo random phase information can be removed effectively by the legitimate receiver. In contrast to the cryptography based encryption algorithms and the conventional PHY secrecy techniques, the main contribution of the proposed scheme is concentrated on the variation in signal's characteristics. Simulation results show that the proposed scheme can prevent the exchanging signal from eavesdroppers' classifi cation or inception. Moreover, the proposed scheme can guarantee the BER performance at a tolerate increasing in computational complexity for the legitimate receivers.

High-precision inductance measurement system based on double-excitation auto-balancing bridge

In order to achieve high precision measurement of inductance in a wide frequency range,a method of inductance measurement based on double-excitation auto-balancing bridge is proposed.In this method,the direct digital synthesizer(DDS)as signal generator is used as the bridge excitation source,and the bridge is automatically balanced by adjusting and measuring the voltage ratio.Using standard resistors,the system can achieve high precision measurement of four-terminal pair inductors in the frequency range of 100Hz-100kHz.Aiming at the low efficiency of bridge balancing,an iterative balancing algorithm based on the steepest descent method is proposed.In order to suppress the interference caused by the initial phase change and non-integer periodic sampling,the high-precision measurement of the complex impedance of inductance is realized based on the all-phase fast Fourier transform(apFFT).Finally,the corresponding measurement system is built and the inductance measurement experiment is carried out.The experimental results show that the relative error of the system for inductance measurement can be as low as 0.009%,and the optimal relative measurement uncertainty of the system can reach 9.89×10^(-4)compared with 5×10^(-5)of commercial impedance analyzer.

A Method of Image Symmetry Detection Based on Phase Information

Traditional methods for detecting symmetry in image suffer greatly from the contrast of image and noise, and they all require some preprocessing. This paper presents a new method of image symmetry detection. This method detects symmetry with phase information utilizing IogGabor wavelets,because phase information is stable and significant, while symmetric points produce patterns easy to be recognised and confirmable in local phase. Phase method does not require any preprocessing, and its result is accurate or invariant to contrast, rotation and illumination conditions. This method can detect mirror symmetry, rotating symmetry and curve symmetry at one time. Results of experiment show that, compared with pivotal element algorithm based on intensity information, phase method is more accurate and robust.

MODELING SOCCER BY MEANS OF RELATIVE PHASE

Soccer is a complex system.Therefore,appropriate(nontrivial) models have to be applied to be able to analyze the behavior of the teams on the pitch.This study analyzed the World Cup Final 2006 between France and Italy by means of relative phase.Mean longitudinal and lateral positions of all 20 outfield players were used to calculate relative phase by Hilbert transformation.Whole team-,group-,and attacker-fullbacks couplings showed that soccer is clearly an in-phase game.Perturbations of the relative phase structure helped to identify scoring opportunities of the attacking team.Moreover,analyses of the relative phase structure can help to understand the complexity of soccer.

Integrated phase unwrapping algorithm for the measurement of 3D shapes by Fourier transform profilometry

An integrated and reliable phase unwrapping algorithm is proposed based on residues and blocking-lines detection, closed contour extraction and quality map ordering for the measurement of 3D shapes by Fourier-transform profilometry (FTP). The proposed algorithm first detects the residues on the wrapped phase image, applies wavelet analysis to generate the blocking-lines that can just connect the residues of opposite polarity, then carries out the morphology operation to extract the closed contour of the shape, and finally uses the modulation intensity information and the Laplacian of Gaussian operation of the wrapped phase image as the quality map. The unwrapping process is completed from a region of high reliability to that of low reliability and the blocking-lines can prevent the phase error propagation effectively. Furthermore, by using the extracted closed contour to exclude the invalid areas from the phase unwrapping process, the algorithm becomes more efficient. The experiment shows the effec-tiveness of the new algorithm.

Generation of Airy beams using a phase-only Fresnel holographic lens

A method to generate Airy beam by combining the Fresnel holographic lens and the cubic phase of Airy beam is proposed. The detailed theoretical derivation to express the optical transform principle of the proposed method is presented. And excellent experimental results are demonstrated. It is shown that this approach works well and simplifies the experimental facility effectively, especially reducing the optical system length to half of that of the conventional method. In addition, the proposed method can realize the beam propagation trajectory control of Airy beam and generate Airy beam array.