Because there is strong time and frequency coupling between the interference and useful signal,so twice square transformation is put forward in this paper to separate the interference and useful signal in freque.
考虑到噪声调频干扰和有用信号之间存在着强的时频耦合,文中采用两次平方变换方法以实现干扰和有用信号的频谱分离,然后通过传统滤波方法将有用信号提取出来。
The mexthod of square transformation to obtain the intersection points of two conical sections that are of the common axis of symmetry is discussed.
论述用平方变换的方法求具有公共对称轴线的二圆锥曲线的交点问题。