计算十字叉丝的在不同距离的衍射图像,有均匀线阵的CRB曲线，直线阵采用切比学夫加权控制主旁瓣比。- Calculation crosshairs diffraction image at different distances, There ULA CRB curve, Linear array using cut than learning laid upon the right control of the main sidelobe ratio.