哈工大信息光学Chapter2-4.pdf

幻 灯 片 Chapter 2 1 Analysis of Two-Dimensional Signals and Systems Yancheng Zhao College of Science Harbin Engineering University 幻 Sketch map: 略图、示意图 灯 Sample 1 片 1 n Determine the 1 2 Fourier transform of 0.5 the function E ( x) 0 E0 sin(2pf p x ) x L E(x ) 0 x L 0.5 1 1 n Make a sketch map 2 1 0 1 2 2 x 2 of F{E(x )}. 幻 灯 n Solution: 片 L F {E (x )} E (x )ei2 pfx dx E 0 sin(2pf p x )e i2pfx dx 3 L E 0 L i 2pf p x i2pf p x i2pfx (e e )e dx 2i L E 0 L i 2p ( f f p ) x i 2p ( f f p ) x [e e ]dx 2i L i 2p ( f f ) L i2p (f f )L i2p (f f )L i2p (f f ) L E 0 e p e p e p e p [ ] 2i i2p (f f ) i 2p (f f )