排序方式: 共有97条查询结果,搜索用时 296 毫秒
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结合外辐射源雷达和天波超视距雷达的体制特点,对短波段可作为辐射源的几种通信信号形式进行了分析,通过仿真和试验验证,给出了外辐射源信号选用依据.首先对短波通信中常用的调幅(AM)、调频(FM)、频移键控(FSK)以及正交频分复用(OFDM)等信号形式进行了仿真分析,给出了信号频谱及模糊函数.试验中根据各信号形式产生相应调制波形,并依靠试验平台进行发射和接收,录取实测数据进行分析.信号分析与评估采用经典线性调频信号为参照信号,探测能力以信噪比和杂噪比为评估依据,根据实测数据给出了各信号形式的评估结果和选用依据. 相似文献
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首先根据天波超视距雷达多功能多任务的需求,结合传输信道电离层和工作频段干扰以及噪声分布等环境特性,介绍了天波超视距雷达任务规划的特点,论述了不同类型目标的探测机理、工作方式和参数设计,并提出了基于环境约束条件的任务规划方法。然后,基于传输损耗、噪声基底和海杂波强度等参量统计结果,以空中目标探测为例,给出了性能评估函数和任务子区规划流程。最后,给出了不同优化准则下的规划结果图,并对结果进行了分析评估。 相似文献
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Fabrizio G. A. Gray D. A. Turley M. D. 《Multidimensional Systems and Signal Processing》2003,14(1-3):241-263
This paper experimentally evaluates the interference cancellation performance of different adaptive beamforming schemes applicable to high frequency (HF) over-the-horizon (OTH) radar systems. Such systems are known to receive multipath and diffusely scattered radio frequency interference produced as a result of reflection from the stratified, dynamic and spatially inhomogeneous ionospheric propagation medium. Apart from quantifying the effectiveness of operational adaptive beamformers in the HF (3–30 MHz) environment, realistic interference models are described and experimentally evaluated in terms of their ability to predict the observed interference cancellation performance which is not well represented by traditional models. Adaptive beamforming algorithms with robustness against jammer motion are also described and their effectiveness is experimentally demonstrated using interference data collected by 32 narrowband receivers of the very wide aperture (2.8 km) Jindalee OTH radar uniform linear array located near Alice Springs in central Australia. 相似文献
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瞬态干扰是天波超视距雷达中一类常见的干扰,会降低雷达目标的可检测性,需要加以抑制。文中分析了雷达接收回波的多普勒频率稀疏性,建立了由潜在回波信号构成的过完备字典,使得雷达接收回波在该字典下有稀疏表示形式,同时提出了基于压缩感知的天波雷达瞬态干扰抑制方法。该方法利用压缩感知重构雷达接收回波,由其代替瞬态干扰位置上的原始信号,从而实现瞬态干扰抑制。实测数据处理证明了该文方法的有效性。 相似文献