利用实时小波降噪的抗电离层闪烁载波跟踪

电离层闪烁影响下的导航信号载波跟踪呈现非平稳、非线性和非高斯特性,这使得传统基于鉴别器和Kalman滤波的载波跟踪改进算法并不能有效减弱电离层闪烁的影响。提出了基于实时小波降噪的抗电离层闪烁载波跟踪算法,其能够更好地刻画闪烁信号的非平稳特性。通过对跟踪环路同相与正交支路的积分结果进行小波降噪,有效滤除了电离层闪烁引入的非高斯噪声,减弱了闪烁对环路鉴别器的不良影响,提高了跟踪环路的精度与稳健性。实验验证了相关分析和小波降噪跟踪算法的有效性。

Carrier Tracking in Presence of Ionosphere Scintillation Using Online Wavelet De-noising

Since carrier tracking in presence of ionospheric scintillation is non-stationary, nonlinear and non-Gaussian, the conventional discriminator or Kalman filter-based methods used to enhance the robustness of tracking loops are less effective. This paper proposes a carrier tracking algorithm for scintillation mitigation based on online wavelet de-noising, which can character the non-stationary scintillation signal much better. By designing a sliding window-based online wavelet de-noising filer after the integration of I and Q channels, the non-Gaussian noise caused by scintillation can be filtered effectively. As a result, the effect of ionospheric scintillation on loop discriminator is mitigated, and the accuracy and robustness of the tracking loop is improved. Experimental results prove the validity of the analysis and the proposed carrier tracking algorithm.