局部傅里叶变换(LFT)是一种重要的纹理特征提取方法。
Local Fourier transform (LFT) is an important texture feature extracting method.
采用了短时傅里叶变换方法对仿真信号进行了时频分析，得到了能够较好地反映目标特征的微多普勒图像。
Short time Fourier transform was used to analyze the simulated signal in the time-frequency domain, a micro-Doppler image that can demonstrate the target characteristics was generated.
实践证明：用基于短时傅里叶变换的瀑布图来分析非平稳信号，具有分辨率高、特征提取结果更为精确的特点。
It proved that using the Waterfall based on Short-Time Fourier Transform to analyze non-balanced signal has many advantages such as.
算法利用了信号进行傅里叶变换后功率谱密度中所包含的信号特征在基带完成，并用软件实现。
This algorithm has utilized the signal to carry on the signal characteristic that Fourier includes in the density of the power spectrum after Fourier transform.
说明：本程序的基本功能是对信号进行傅里叶变换，并同时提取出他的时域和频域的特征值。
The basic function of this program is the signal to Fourier transform, and the simultaneous extraction of his time domain and frequency domain characteristic values.
依据离散傅里叶变换性质，推导出离散傅里叶变换的不变特征，并将其用于人脸图像识别。
Then according to the properties of discrete Fourier transform, it deduces the discrete Fourier invariant features that are employed on facial image recognition.
采用傅里叶变换红外光谱表征了聚甲基丙烯酸丁酯（PBMA）共混改性有机硅树脂前后的结构特征；
The molecular structure of the silicone resin pre-and post-blending modification by poly (butyl methacrylate)(PBMA) was characterized by Fourier transform infra-red spectrometry.
试验结果表明，变窗移傅里叶变换算法正确可行，可有效提取旋转机械振动信号转速谱阵的特征信息。
The experimental results show that it is correct and feasible, and can extract characteristic information of the rotating speed spectral map effectively.
提出了一种基于机器视觉与离散傅里叶变换的目标特征识别方法。利用计算机图像技术采集和处理图像信号；
A identifying image methods based on machine vision and DFT are studied, The images are collected and video signal is processed using computer technology.
基于短时傅里叶变换形成的三维谱图，采用数字图像处理的方法提取信号的特征。
A Surface EMG signal identification method based on short time Fourier transform is presented in this paper.
应用快速傅里叶变换算法对靶丸圆周轮廓数据进行分析，获得了靶丸表面外轮廓或内轮廓模数-功率谱特征曲线。
The power spectra curve as a function of the mode number of outer or inner profiles are also calculated by the application of fast Fourier transform to the circumferential profile data.
应用快速傅里叶变换算法对靶丸圆周轮廓数据进行分析，获得了靶丸表面外轮廓或内轮廓模数-功率谱特征曲线。
The power spectra curve as a function of the mode number of outer or inner profiles are also calculated by the application of fast Fourier transform to the circumferential profile data.
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