基于Daubechies小波的X射线脉冲星信号降噪研究

针对X射线脉冲星弱信号埋没在强噪声中，在短时间内周期叠加的脉冲轮廓的信噪比低，影响脉冲到达时间的估计精度和效率，提出基于Daubechies小波的X射线脉冲星信号降噪的算法。在对RXTE观测数据预降噪处理和周期叠加的基础上，采用Daubechies小波算法做降噪处理，使得较短的时间内仍能获得高信噪比的脉冲轮廓。利用RXTE观测数据进行验证仿真，结果表明，该算法能有效滤除X射线脉冲星信号所包含的设备及空间环境的噪声，在保证脉冲到达时间精度的情况下，缩短了观测时间，提高X射线脉冲星导航的效率。 

Daubechies Wavelet Based Denoising Method for X ray Pulsar Signal #br#

The X ray pulsar with weak signal buried in strong noise leads to the low signal to noise ratio of folded pulse profiles in short time, both estimation accuracy and efficiency are affected. A denoising method for X ray pulsar is proposed in the paper. By preprocessing and folding the pulse profiles, and the measured data are employed for Daubechies wavelet, the SNR of pulse profile is improved. The RXTE data are used for verification and the simulation results show the method proposed can eliminate the noise from equipments and space environment, thus shorting the observing time and improving the efficiency of X ray pulsar navigation without reducing the accuracy of TOA.