FRFT Source Code and LFM Signal Detection Implementation

This package contains two key programs: the first is the fundamental FRFT source code implementation, and the second applies FRFT for linear frequency modulation (LFM) signal detection. The underlying principle involves performing fractional Fourier transforms on observed signals using different transformation orders (various fractional domains) as variables, generating a two-dimensional distribution of signal energy across the time-frequency plane. The implementation typically utilizes discrete FRFT algorithms with order sampling to create this distribution matrix. On this plane, we conduct two-dimensional peak search by applying amplitude thresholds - typically implemented through matrix peak detection algorithms like findpeaks() in MATLAB. This process enables effective LFM signal detection and parameter estimation (including center frequency and chirp rate) through peak coordinate analysis. The method significantly enhances detection accuracy and reliability by leveraging the signal concentration properties in optimal fractional domains.