查询词典 anti-aliasing

First,this dissertation presents a new method of cyclic spectra estimation which uses time aliasing method and sidelobe eliminated ssinc window which were presented by Smith in 1994 in it.

首先，本文将1994年Smith提出的时间重叠法和具有旁瓣抑制能力的ssinc窗应用于循环谱估计中，提出了TA循环谱估计方法。

In certain wireless channel, the Doppler frequency shift will be caused by wireless channel output signal aliasing.

在某些无线信道中，多普勒频移会引起无线信道输出信号的混叠。

In order to overcome the aliasing phenomenon commonly existing in real contourlet transform image denoising, some characters of complex contourlet transform whose structure is a cascading of dual tree complex wavelet and directional filter banks are discussed. It is proved that the transform performs well at division and restraining ability under white Gaussian noise condition. Then, an image denoising algorithm was proposed based on the transform.

为了克服实轮廓波图像消噪后广泛存在的混叠现象，研究了基于双树复小波级联方向滤波器架构的复轮廓波变换图像消噪的若干性质，证明了对于高斯白噪声图像，该变换具有更好的分割能力和抑制能力，并在此基础上提出了一种基于该变换的图像消噪算法。

In this dissertation, digital lock-in detection techniques under integer period sampling and non-integer period sampling are separately investigated (1) Under integer period sampling, digital signal sequence is acquired through sampling the measured signal, but digital reference sequence is acquired through mathematical operation, then digital lock-in detection can be realized by calculating crosscorrelation function of digital signal sequence and digital reference sequence Harmonic measure is also analyzed, and a method of measuring harmonic of a periodic signal under aliasing is put forward.

本文对使用采样ADC把模拟信号转换为数字信号并通过计算数字信号的相关函数来实现锁定检测的技术进行了研究，在此基础上设计了一个多功能的数字LIA并在一些科学实验中进行了应用。本文对整周期采样和非整周期采样时的数字锁定检测技术分别进行了研究。(1)在整周期采样时，对被测信号进行采样得到信号序列，而参考序列由数学运算得到，通过计算信号序列和参考序列的互相关函数就可实现锁定检测。

In chapter 4, the Newlands harmonic wavelet is improved and a new type of wavelet with better time-frequency characteristic is constructed. Frequency band of signal can be divided arbitrary with the improved harmonic wavelet so that the phenomena of aliasing are reduced. Several typical fault signals in Electromechanical System are analyzed with it. In addition to the improved harmonic wavelet in chapter 4, a new half-complex wavelet is presented to improve the complex wavelet, which is given by Chaari.O. A unilateral recursive algorithm is derived to improve the real-time characteristic. A parameter n is imported to make the time-frequency and filtering characteristics of it better and its ability of extracting fault feature is enhanced.

第四章通过对Newland谐波小波的改进构造频域紧支撑、时域性能良好的新型小波函数，可实现信号频带的任意划分，从而减少频带混叠现象，采用改进的谐波小波对多种典型的机电系统故障信号进行了分析；以Chaari.O复小波为基础构造了一个半复小波，从提高复小波算法的实时性出发，推导了半复小波单向递推算法，通过给原小波设置可调参数的方法，实现了一种能满足小波基本条件的复值小波，可以通过参数的调整调节小波滤波器在Hilbert空间的时频特性和相应的滤波性能，以加强半复小波对故障特征的提取能力。

First, by the style of convolution and deconvolution operator in frequency domain, the aliasing problem in parabolic Radon transform is researched, and the critical sample of the parameter q and x is formulated.

首先通过频率域中褶积和反褶积算子的形式，对抛物线Radon变换中的假频问题进行了研究，得出了变量q和x的临界采样率的定量公式。

Phase theory analysis of spatial integral sampling provide theoretical basis for under sampling aliasing reduction.

空间积分抽样相位理论分析为消减欠采样产生的折叠混淆效应提供了理论依据。

Trace interpolation plays an important role in seismic data processing. Spatial aliasing is a principal troublesome problem in seismic trace interpolation.

道间插值方法在地震资料处理中具有十分重要的作用，而地震道空间内插所面临的主要问题是空间假频。

With the development of computer and graphics technology, the advanced dashboard of an aircraft has brought about a great challenge to the quality of the graphics.Based on the cause of the aliasing, the thesis below puts forward a new method using Gaussian Integration to get rid of it and offers detailed mathematical deduction as well. Furthermore, the practical generation of rhumb lines has proved the effectiveness of the new method

随着计算机及图形学技术的发展，座舱仪表对图形显示的质量提出了更高的要求，本文主要从图形走样产生的根本原因出发，提出利用高斯积分法来消除走样现象，且给出了较详细的数学推导，并将此算法应用于罗盘刻度线的生成，效果比较明显。

Also,it can overcome frequency aliasing effect in general subband coding,and is more flexible than the resolution-layered coding which uses temporal subsampling and spacial filter.

另外，它比采用时间方向亚抽样和空间滤波器的分辨率分层方法更灵活，并克服了频率混叠现象。

You can do some assertiveness training.

你可以进行一些自信训练。

We were well on the path to making a rear-wheel-drive global platform," says Mays."

我们正致力于建立一个后轮驱动的平台，"Mays这样说道。"