Since the dsss signal is always transmitted in seriously noisy environment , the dsss signal detection with low signal - to - noise ratio is an important content of dsss electronic countermeasures 由于dsss信号通常淹没在背景强噪声中传播,因此,在低信噪比下对dsss信号的检测是直扩电子对抗的重要内容。
By analyzing the basic model in the theory , we can come to the conclusion that the mod . external model can be used when high snr , while the seds + ecc mode can be used when low snr 通过对基本模型的理论分析,得出在高信噪比时应采用纠错码外部反馈改进型,而在低信噪比时应采用纠错码级联改进型的结论。
Wide doppler range . varied code length , varied code rate , which have more difficulties . little acquisition time and high acquisition probability are required during the capturing process of spread spectrum signals 对高动态、高码率、低信噪比、大多普勒及变化的码长和码率的扩频信号的快捕是本文的难点。
With the combination of noise estimation and the speech enhancement algorithms , this thesis did lots of experiments at low snr environment and analyzed the simulation results 在此基础上,结合前面的改进噪声参数估计方法,对各种语音增强算法及其改进方法进行了低信噪比环境下的系统仿真,并对实验结果进行了比较和分析。
With complicated surface and underground geologic conditions , several problem that qaidam basin has been facing with includes not - ideal static correction and low signal - to - noise while seismic data processing 摘要柴达木盆地复杂的地表地质条件和地下地质条件，使其在地震资料处理中存在着严重的静校正和低信噪比问题。
Objective to find a useful index for real - time detecting of speech endpoint and improving the performance of speech processing under low snr by analyzing fluctuation complexity of speech signals 摘要目的研究基于涨落复杂性测度的语音特征提取，提高低信噪比语音端点检测的正确率和鲁棒性，从而改善语音处理和分析的性能。
Many new uwb radar signal parameter estimation algorithms based on sub - nyquist sampling have been deeply and widely studied in this dissertation . linear frequency modulated ( lfm ) signal is concerned here 本论文针对超宽带雷达信号中主要的信号形式?线性调频信号在低信噪比和欠采样的条件下的参数估计进行了分析、仿真和探讨。
Numerical results show that for the data with either high or low signal to noise ratio ( snr ) , inversion solution depends weakly on regularization operators , while strongly upon regularization parameter 模拟表明，无论是高信噪比数据，还是低信噪比数据，反演的含水量在小正则化参数时，对模型约束的依赖性不大，主要受正则化参数影响。
This article works over a mathod named large step fast acquisition to capture the pn code in the receiver , which was originally put forward for the acquisition and synchronization of long pn code under the condition of low signal to noise ratio ( s / n ) 本文主要研究了大步进快速捕获法，该方法是针对低信噪比下长扩频码的捕获和同步问题提出的。
This dissertation makes a deeply research on weak signals detection using different chaos oscillators such as duffing systems and lorenz systems , getting hold of the effective detection methods in low snr 本文全面深入研究了混沌振子在微弱信号检测中的应用问题,研究了利用非线性振动系统对不同信号的检测,得到了低信噪比条件下信号检测的有效方法。
