| 1. | On frequency resolution of the windowed discrete fourier transform
加窗离散傅里叶变换测频分辨率研究 |
| 2. | Dft eiscrete fourier transformation
离散傅里叶变换 |
| 3. | Dft for discrete fourier transform
离散傅里叶变换 |
| 4. | Pulse step return loss from measurement in the frequency domain using the inverse discrete fourier transformation
用反离散傅里叶变换法测定频域中脉冲阶跃回程损耗 |
| 5. | According to the theory of digital signal processing , discrete fourier transform has selectivity to frequency just as spectrum analyzer
根据数字信号处理理论，离散傅里叶变换( dft )算法对频率具有选择性，有相当于频谱仪的功能。 |
| 6. | For the dft - based coriolis mass flowmeter , the key problem that greatly influence its precision is how to realize the integral period signal samples
摘要对基于离散傅里叶变换( dft )信号处理方式的柯氏质量流量计来说，影响其精度的关键问题是如何实现信号的整周期采样。 |
| 7. | With reasonable constraint and the assistant of special - designed pilot sequence for each user , the discrete fourier transform ( dft ) - based uplink channel estimation algorithm can achieve good estimation accuracy without sacrificing much system capacity
在合理约束条件以及为每个用户特殊设计的导频序列辅助下，基于离散傅里叶变换( dft )的上行信道估计算法能够获得较好的估计精度，同时无需牺牲过多的系统容量。 |
| 8. | Wavelet analysis and neural network have been researched . based on bp neural network , analysing the features of the bp neural network ' s activation function and the structure of the bp neural network , wavelets neural network is constructed with wavelet function . fourier transform has a important role on signal processing , so the fourier transform is introduced . a function ' fourier transform is analysed . after introducing the concept of the wavelet analysis , a serval wavelet functions is given out , so the knowledge of wavelet analysis is better understood . the multiresolution analysis has a important role on constructing wavelet function and understanding the wavelet transform
小波分析和神经网络得到了广泛的研究，小波神经网络是在bp神经网络的基础上，考虑和分析了bp神经网络的激励函数的特点，以及bp神经网络的结构，结合了小波分析的知识而构造的。傅里叶变换在信号的处理起重要的作用，所以介绍了傅里叶变换、离散傅里叶变换和加窗傅里叶变换，并对一函数作离散傅里叶变换分析。 |
| 9. | The fundamental theory for digital lensless fourier transform holography and its applications in 3 - d object reconstruction and optical metrology are presented in this dissertation . ( 1 ) analytical foundation for numerical reconstruction of digital lensless fourier transform holography , namely discrete fourier transform theory , is presented . the basic principle and mathematical model for recording and numerical reconstruction of digital lensless fourier transform hologram is elaborated
主要内容包括： ( 1 )讨论了数字无透镜傅里叶变换全息术数值重建的数学基础? ?离散傅里叶变换的基本理论，分析了数字无透镜傅里叶变换全息图记录与再现的基本原理，建立了数字无透镜傅里叶变换全息图记录与再现的数学模型。 |
| 10. | By storing a beacon image in aircraft as reference and regarding actual beacon image as the sum of reference image and additive gaussian white noise , the values of rotation and translation for beacon image were calculated according to phase correlation and dft ( discrete fourier transfer )
该方法的原理是在航天器上存储一幅信标图像作为参考，把实际信标图像看成参考信标图像和附加高斯白噪声和的形式，基于离散傅里叶变换和相位相关技术对信标的旋转因子和平移因子进行计算。 |
