项目名称: 基于相空间挤压策略的空间信号时频分析与参数估计方法研究
项目编号: No.61501366
项目类型: 青年科学基金项目
立项/批准年度: 2016
项目学科: 无线电电子学、电信技术
项目作者: 王平
作者单位: 西安空间无线电技术研究所
项目金额: 23万元
中文摘要: 时频分析和参数估计是空间信号处理和解译中的重要环节,精确的时频表示对于空间信号的噪声压制、信号分离和目标特征提取至关重要。目前常用的时频分析方法,如短时傅里叶变换和小波变换等用于空间信号时频分析时具有局限性,主要体现在由于时频原子的影响,导致信号在时频平面上的能量扩散和时频分辨率的下降。本项目拟将新的时频分析工具——基于相空间挤压策略的变换(SST)用于空间信号分析与处理。该变换通过对变换域系数的重排,获得一个更加聚集的时频表示,时频分辨率大大提高。本项目首先解决SST存在的函数适应性、基函数选取等一系列理论问题。在此基础上,针对空间信号受噪声影响大,给信号分析和参数估计带来的困难,建立基于SST的有效信号能量分布空间的自动划分理论,提出基于SST的参数估计方法。本项目可以为空间信号的时频分析和参数估计提供一种新的途径,为空间信号处理和解译提供有效的方法和技术。
中文关键词: 时频分析;参数估计;小波变换;挤压策略;空间信号
英文摘要: Time-frequency analysis and parameter estimation play important roles in spatial signal processing and interpretation. An accurate time-frequency representation is important for noise suppression, signal separation and feature extraction. The popular methods, like short-time Fourier transform and wavelet analysis have limitations in dealing with spatial signal. Due to the effect of the time-frequency atoms, the energy of signal spread out in transformed domain, which leads to blurred time-frequency representations. We introduce the Synchrosqueezing transform (SST) with application to spatial signal time-frequency analysis. This new transform reallocates the coefficients of transformed domain to get a concentrated time-frequency map with high resolution. We focus on the theoretical issues in SST, such as the choice of the atom and the applicability analysis. As the spatial signal analysis and parameter estimation are sensitive to noise, we propose a method to determine the distribution of the effective signal in the transformed domain. Then, we calculate the parameters using SST. We explore a new approach for time-frequency analysis and parameter estimation of spatial signal and present contributions on spatial signal processing and interpretation.
英文关键词: Time-frequency analysis;Parameter estimation;Wavelet transform;Synchrosqueezing transform;Spatial Signal