To the problem of the unknown underwater target detection, according to the feature that the underwater target radiated noise contains the stable line spectrum, a weighted method based on the main-to-side lobe ratio ...To the problem of the unknown underwater target detection, according to the feature that the underwater target radiated noise contains the stable line spectrum, a weighted method based on the main-to-side lobe ratio （MSLR） is proposed for broadband beam-forming. This weighted method can be implemented by using the following steps. Firstly, optimize the spatial spectrum of each frequency unit by the second-order cone programming （SOCP）, and obtain the optimized spatial spectrum with lower side lobe. Secondly, construct weighting factors based on the MSLR of the optimized spatial spectrums to from weight factors. Lastly, cumulate the spatial spectrum of each frequency unit via the weight statistical method of this paper. This method can restrain the disturbance of background noise, enhance the output signal-to-noise ratio （SNR）, and overcome the difficulty of traditional four-dimensional display. The theoretical analysis and simulation results both verify that this method can well enhance the spatial spectrum of line spectrum units, restrain the spatial spectrum of background noise units, and improve the performance of the broadband beam-forming.展开更多
为了提高高轨电子侦察卫星对雷达信号的侦收灵敏度,增大截获概率,提出了一种基于天线波束偏转的雷达主瓣侦收方法。根据雷达辐射源最大仰角,高轨卫星可以获得雷达信号的主副瓣侦收区域。通过天线波束在短时间内进行特定方向和一定角度...为了提高高轨电子侦察卫星对雷达信号的侦收灵敏度,增大截获概率,提出了一种基于天线波束偏转的雷达主瓣侦收方法。根据雷达辐射源最大仰角,高轨卫星可以获得雷达信号的主副瓣侦收区域。通过天线波束在短时间内进行特定方向和一定角度的偏转,使指向雷达副瓣的天线波束实时对准雷达主瓣侦收区域,实现雷达主瓣侦收。仿真实验结果表明:取雷达主瓣最大仰角为40°、天线波束宽度为2°,通过天线波束偏转7.6°,可完成雷达辐射源主瓣侦收;与副瓣侦收相比,主瓣侦收信号信噪比至少可提高12.24 d B。展开更多
基金supported by the National Natural Science Foundation of China(Grant No.61372180)the National Key Scientific Instrument Equipment Development Project of China(Grant No.2013YQ140431)
文摘To the problem of the unknown underwater target detection, according to the feature that the underwater target radiated noise contains the stable line spectrum, a weighted method based on the main-to-side lobe ratio （MSLR） is proposed for broadband beam-forming. This weighted method can be implemented by using the following steps. Firstly, optimize the spatial spectrum of each frequency unit by the second-order cone programming （SOCP）, and obtain the optimized spatial spectrum with lower side lobe. Secondly, construct weighting factors based on the MSLR of the optimized spatial spectrums to from weight factors. Lastly, cumulate the spatial spectrum of each frequency unit via the weight statistical method of this paper. This method can restrain the disturbance of background noise, enhance the output signal-to-noise ratio （SNR）, and overcome the difficulty of traditional four-dimensional display. The theoretical analysis and simulation results both verify that this method can well enhance the spatial spectrum of line spectrum units, restrain the spatial spectrum of background noise units, and improve the performance of the broadband beam-forming.
文摘为了提高高轨电子侦察卫星对雷达信号的侦收灵敏度,增大截获概率,提出了一种基于天线波束偏转的雷达主瓣侦收方法。根据雷达辐射源最大仰角,高轨卫星可以获得雷达信号的主副瓣侦收区域。通过天线波束在短时间内进行特定方向和一定角度的偏转,使指向雷达副瓣的天线波束实时对准雷达主瓣侦收区域,实现雷达主瓣侦收。仿真实验结果表明:取雷达主瓣最大仰角为40°、天线波束宽度为2°,通过天线波束偏转7.6°,可完成雷达辐射源主瓣侦收;与副瓣侦收相比,主瓣侦收信号信噪比至少可提高12.24 d B。
