ID 原文 译文
20845 在逆合成孔径雷达(ISAR)成像中，由距离多普勒或时频分析方法得到的ISAR图像方位向仅是目标的多普勒频率分布，不能反映目标的真实形状，需对ISAR图像进行方位定标。 For the Inverse Synthetic Aperture Radar (ISAR) imaging, the ISAR image obtained by the Range-Doppler (RD) or time-frequency analysis methods can not display the target's real shape due to its azimuth relating to the target Doppler frequency, thus the cross-range scaling is required for ISAR image.
20846 该文提出一种快速的ISAR方位定标方法来估计目标的旋转角速度(RAV)。 In this paper,a fast cross-range scaling method for ISAR is proposed to estimate the Rotational Angular Velocity (RAV).
20847 首先，该方法利用高效的伪逆极坐标快速傅里叶变换把两幅不同时刻ISAR图像的旋转运动转化为沿极角的平移运动。 Firstly, the proposed method utilizes efficient Pseudo Polar Fast Fourier Transform (PPFFT) to transform therotational motion of two ISAR images from two different instant time into translation in the polar angledirection.
20848 然后，在极坐标域定义了一种新的积分相关代价函数来粗估目标的RAV。 Then, a new cost function called integrated correction is defined to obtain the RAV coarseestimation.
20849 最后，通过采用二分法估计得到最优的RAV，进而实现ISAR方位定标。 Finally, the optimal RAV can be estimated using the Bisection method to realize the cross-range scaling.
20850 相比于现有方位定标算法，所提方法避免了插值操作带来的精度损失和高计算复杂度问题。 Compared with the available algorithms, the proposed method avoids the problems of precision loss and high computational complexity caused by interpolation operation.
20851 计算机仿真和实测数据实验结果证明了所提方法的有效性。 The results of computer simulation and realdata experiments are provided to demonstrate the validity of the proposed method.
20852 星历误差是导致同步三星时差定位系统定位误差的主要因素，该文针对传统差分校正算法在远离参考站区域对星历误差校正精度差的问题，提出一种基于虚拟参考站(VRS)的广域差分校正算法。 A wide area difference calibration algorithm based on Virtual Reference Station (VRS) for tri-satellite Time Difference Of Arrival (TDOA) geolocation system is proposed to solve the problem that traditional difference calibration algorithm can not eliminate the location error caused by ephemeris error completely, especially when the emitter source is far away from the calibration station.
20853 首先证明两参考信号时差的差分残差近似为两参考站连线方向的线性函数； Firstly, TDOA measurements of theVRS, which is in the vicinity of emitter source, is estimated by using TDOA measurements of reference station.
20854 然后利用已有参考站的位置信息和参考信号的时差观测值，在目标辐射源位置处通过线性拟合构造一个VRS； Then, in order to remove the effect of ephemeris error and synchronization error on location error, TDOAmeasurements of the VRS is subtracted from that of emitter source.