双基地高频地波雷达系统矢量流速探测精度分析

Analysis of the Vector Current Velocity Detecting Precision of Bistatic High-frequency Ground Wave Radar System

随着高频地波雷达海流探测技术的日益成熟,海流测量精度得到了海洋学者的高度关注。该文旨在分析T/Rm-Rb双基地雷达系统的矢量流速探测精度,得到该系统进行矢量流速探测的最佳工作区域。文章首次从矢量流速度的均方误差角度进行分析。首先将T/Rm单基地雷达测得的径向流速度和T-Rb双基地雷达测得的双曲流速度进行组合得到矢量流速度;然后通过全微分得到矢量流速度的误差,并分成I型误差(测量多普勒速度的有限分辨率引起的误差)和II型误差(观察散射角时的误差)来讨论其均方误差;最后绘制均方误差的水平分布图,确定矢量流速探测的最佳工作区域,即:T/Rm-Rb双基地雷达系统在提取矢量流速时,应尽量避免基线和双基地接收机Rb附近的区域。

With the maturity of current detecting technology based on high-frequency ground wave radar, current detecting precision has gained increasing attention. This paper aims at discussing the vector current velocity detecting precision of T/Rm-Rb system from the mean square error, and obtaining the optimal operating region of current velocity detecting. Firstly, the vector current velocity is obtained from the radial current velocity measured by T/Rm monostatic radar system and the hyperbolic current velocity measured by T/Rb bistatic radar system. Then the vector current velocity error is calculated from total differential and divided into I type error and II type error to discuss the mean square error. I type error means the error resulted from the limited Doppler velocity resolution and II type error means the error resulted from the scattering angle observing. Finally, the geometrical dilution of position is drawn and the optimal operating region of current velocity detecting is obtained. That is： the region near the baseline and the bistatic receiver Rb should be avoided for vector current velocity detection of T/Pm-Rb system.