分数阶回波ambiguity函数

Fractional ambiguity function

本文通过分数阶Fourier变换定义了分数阶(互)模糊函数,并探讨了它的性质.作者首先说明当回波时延为!0,频偏为"0时,回波的分数阶模糊函数模的峰值点在(!,u)平面内移动了(!0,"0sin#+!0cos#).但是要注意的是,(0,0)并不一定是分数阶模糊函数模的极大值点.然后作者进一步说明当参考信号为二次调频信号时,分数阶模糊函数有一个冲激,具有类似图钉形的良好性质,因此在雷达动目标检测中有良好的应用前景.

The fractional cross ambiguity function is defined by fractional Fourier transform. Its proper- ties are investigated. When the delay and Doppler of moving target signal are τ0 and ξ0 respectively, the peak point of the fractional ambiguity function has shifted （τ0,ξ0sinaα＋τ0cosα） in the （τ, u） plane. It should be noted that （0, 0） is not always the peak point of fractional ambiguity function. We also point out that when the reference signal is quadratic frequency-modulated signal, the fractional ambiguity function has narrow peak and low sidelobes.