频变换 meaning in Chinese
frequency translation
Examples
- The fractional fourier transform is linear time - frequency transform , and it doesn ’ t have disadvantages of wigner - ville distribution . moreover , the precision of this method is higher , and the performance of antinoise is better
而分数阶傅立叶变换是线性时频变换,所以它不受交叉项的干扰,没有不模糊区间减半的缺点,而且它的估计精度高、抗噪性能好。 - As the targets flying in groups may spread over several range of cells and their doppler frequencies are time * . varying , a scheme of target number detection in groups on a conventional low * . resolution radar is proposed based on a time * . range * . doppler image cube which is constructed by substituting a time * . frequency transform for the fourier transform in the conventional range * . doppler imaging
针对实际编队目标在距离上的分布特性和目标多普勒频率的变化规律，利用联合时频变换代替传统傅立叶变换，建立目标时间-距离-多普勒立体像，提出一种基于立体像的目标架次检测方法。 - Some valuable conclusions are summarized by theoretical analysis and simulation experiments : from the side of signal processing , pulse jamming can be deleted by the method of time - domain sliding window accumulation and can be restored by interpolative prediction . ; gauss white nose can be attenuated while jamming disperse point - target by the method of time - frequency analysis in time - frequency domain . ; radio frequency noise jamming can be deleted by the method of average range frequency spectrum and notching in frequency domain
通过大量的理论分析和仿真实验，得到了一批具有一定价值的结论：从信号处理的角度出发，对于脉冲式干扰，能够运用时域滑动窗口积累的方法去掉，并且通过预测插值得到较好的恢复；对于高斯白噪声干扰，在时频变换域内应用时频分析方法可减小其对分散点目标的干扰；对于射频噪声，通过平均距离频频法和频域陷波的方法可以去掉；从改变合成孔径雷达系统角度出发，类似双基地雷达能够避免各种干扰，对发射信号进行调幅，调相以及改变调频斜率都是较好的抗干扰方法。