| 1. | In this paper , a pulsar de - dispersion algorithm based on the short time fourier transform ( stft ) is presented
摘要叙述了一种基于短时傅立叶变换的脉冲星消色散算法。 |
| 2. | Secondly the short time fourier transform ( stft ) algorithm is also introduced and a de - dispersion algorihm is proposed based on it
接着介绍了短时傅立叶变换，并在此基础上提出了一种基于短时傅立叶变换的消色散算法。 |
| 3. | In the past , we used to analyze speech signal and filter the noise by short - time fourier transform in the frequent domain . however , this method is not effective to the white noise
在过去，我们一般使用短时傅立叶变换( sfft )在频域内对语音信号进行分析降噪，但是对于白噪音，这种方法的效果往往不尽人意。 |
| 4. | A rational analysis is needed . there are many methods in harmonic analysis , such as traditional fast fourier transform , short time fourier transform and wavelet transform . they have different analytical emphasis
谐波分析方法众多，主要有传统的快速傅立叶变换、短时傅立叶变换和小波变换，它们分析的侧重点有很大不同。 |
| 5. | The computer simulations show the validity of the models . 3 . joint estimation of the time delay and doppler frequency based on short - time fourier transform ( stft ) and time - frequency analysis are studied to estimate the parameters of the underwater target echo
针对主动回波信号参量的估计问题，重点研究了利用短时傅立叶变换、时频分析进行时延和多普勒频移联合估计，进而进行目标距离和速度参数的估计。 |
| 6. | Based on the different work states of engine , the engine vibration signal collected in it ' s steady work conditions is analysed by the technique of confrequency spectrum ; the signal related to the fast run - up state is processed by stft and wavelet analysis
根据发动机的工作特点，将振动信号分为稳态振动信号和过渡态振动信号。稳态信号采用传统的傅立叶分析方法，过渡态信号采用了短时傅立叶变换和小波方法。 |
| 7. | 2 . discuss the discrete form of time - frequency analysis ; give the simulations of wigner - ville distribution and short time fourier transform under different snr . at same time , to overcome the cross - term of wvd , choi - williams distribution and b - distribution are introduced
以wvd为研究重点，对时频分析的概念、性质做系统的介绍；给出常用的时频分析形式，例如短时傅立叶变换、 wigner ? ville分布；最后给出时频分析的一般定义。 |
| 8. | In this thesis , the necessity of exerting the condition monitoring of the high voltage circuit breaker is discoursed , and the vibrant condition monitoring is researched and discussed . stft ( short - time fourier transform ) method is utilized to analyze the vibrant signal comparing with other analysis methods
本文论述了实施高压断路器状态监测的必要性，对断路器振动状态监测做了探讨和研究，通过分析比较，选用短时傅立叶变换作为振动信号的分析方法。 |
| 9. | The other research purpose is to discover characteristic information and reliable methods of reflecting spinal cord damage . due to typical damage indicators , amplitude and latent period , have bugs such as limited information and weak stabilities , this project recommends applying time - frequency analysis to monitoring spinal cord function . through analysing and comparing typical signal with stft and cwt , it is proved indicators under time - frequency distribution can be better in reflecting signal changes , espcially the wavelet transformation
针对目前ep监测中判定脊髓损伤的指标（波幅和潜伏期）存在信息量相对较小、稳定性较差的缺陷，本课题提出利用时频分析技术对术中脊髓功能监护进行研究，通过短时傅立叶变换和小波变换分析和比较典型信号的时频分布，证明时频特征参数能更有效的提取信号的变化信息。 |
