摘要
论述了X射线脉冲星辐射光子探测与累积脉冲轮廓构造模型,分析了通过光子计数获取的累积脉冲轮廓的噪声特点,提出了基于非归一化Haar小波的消噪算法,推导了基于Haar小波消噪的阈值函数的最佳参数计算公式。在X射线脉冲星导航地面模拟系统上进行了实验研究,结果表明,消噪后的累积脉冲轮廓峰值信噪比提高2dB以上。通过蒙特卡罗模拟分析,证实消噪后的累积脉冲轮廓有助于提高脉冲到达时间的测量精度。
The photon detection model of X-ray pulsar and the construction of pulsar integrated pulse profile are discussed. The characteristics of pulse profile which is reconstructed by the way of photon counting are analyzed. A de-noising algorithm based on non-normalized Haar wavelet is proposed, and the optimal parameters for wavelet threshold function are derived based on Haar wavelet. The experimental study is done in the ground simulated experimental system for X-ray pulsar navigation. Experimental results show that the peak signal-to-noise ratio can be improved by at least 2 dB, and the accuracy of time-of-arrival （TOA） measurement is also improved, which is proved by Monte Carlo simulation.
出处
《光学学报》
EI
CAS
CSCD
北大核心
2011年第8期13-19,共7页
Acta Optica Sinica
关键词
测量
脉冲星导航
脉冲轮廓
泊松分布
峰值信噪比
HAAR小波
measurement
pulsar navigation
pulse profile
Poisson distribution
peak signal-to-noise ratio
Haarwavelet
