针对雷达运动平台速度未知的情况下,二维目标检测算法会出现虚警现象导致雷达无法正常工作的问题,提出了一种基于杂波频谱统计的非平稳平台雷达与目标速度估计的方法,即线性调频连续波(Linear Frequency Modulated Continuous Wave,LFM...针对雷达运动平台速度未知的情况下,二维目标检测算法会出现虚警现象导致雷达无法正常工作的问题,提出了一种基于杂波频谱统计的非平稳平台雷达与目标速度估计的方法,即线性调频连续波(Linear Frequency Modulated Continuous Wave,LFMCW)毫米波雷达在非平稳运动平台下,通过恒虚警(Constant False Alarm Rate,CFAR)来提高目标检测性能的同时,对杂波频谱数据的特点进行分析、统计得到雷达运动平台和目标的速度,实验结果通过均方根误差(Root Mean Square Error,RMSE)来验证准确性,实验结果表明,上述算法在四种杂波背景复杂的场景下,对雷达运动平台速度估计的均方根误差平均为0.056m/s,对目标速度估计的均方根误差平均为0.073m/s,实验结果的准确性较高。展开更多
The response of dynamic wave pressures on structures would be more complicated and bring about new phenomena under the dynamic interaction between soil and structure. In order to better understand the response charact...The response of dynamic wave pressures on structures would be more complicated and bring about new phenomena under the dynamic interaction between soil and structure. In order to better understand the response characteristics on deeply embedded large cylindrical structures under random waves, and accordingly to offer valuable findings for engineering, the authors designed wave flume experiments to investigate comparatively dynamic wave pressures on a single and on continuous cylinders with two different embedment depths in response to two wave spectra.The time histories of the water surface elevation and the corresponding dynamic wave pressures exerted on the cylinder were analyzed in the frequency domain. By calculating the transfer function and spectral density for dynamic wave pressures along the height and around the circumference of the cylinder, experimental results of the single cylinder were compared with the theoretical results based on the linear diffraction theory, and detailed comparisons were also carried out between the single and continuous cylinders. Some new findings and the corresponding analysis are reported in present paper. The investigation on continuous cylinders will be used in particular for reference in engineering applications because information is scarce on studying such kind of problem both analytically and experimentally.展开更多
文摘The response of dynamic wave pressures on structures would be more complicated and bring about new phenomena under the dynamic interaction between soil and structure. In order to better understand the response characteristics on deeply embedded large cylindrical structures under random waves, and accordingly to offer valuable findings for engineering, the authors designed wave flume experiments to investigate comparatively dynamic wave pressures on a single and on continuous cylinders with two different embedment depths in response to two wave spectra.The time histories of the water surface elevation and the corresponding dynamic wave pressures exerted on the cylinder were analyzed in the frequency domain. By calculating the transfer function and spectral density for dynamic wave pressures along the height and around the circumference of the cylinder, experimental results of the single cylinder were compared with the theoretical results based on the linear diffraction theory, and detailed comparisons were also carried out between the single and continuous cylinders. Some new findings and the corresponding analysis are reported in present paper. The investigation on continuous cylinders will be used in particular for reference in engineering applications because information is scarce on studying such kind of problem both analytically and experimentally.