The paper, through analyzing the forming of the amplitude spectrum of the echo, proposed a new method using quadratic curve fitting for it.

本文针对这种情况，对连续波雷达回波频谱幅度产生原因进行分析，提出了二次曲线拟合频谱幅度来估计加速度的方法。

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But the quadratic curve can be used only in condition when each X-coordinate of the points sequence mapping to only one Y-coordinate, so it can't be used in fitting closing curve.

但二次多项式只能拟合x坐标与Y坐标之间成函数关系的点序列，无法拟合闭合曲线。

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