解析信号 fa(t)=f(t)+f(t) F(O=F(O)+il-jsgn F(@=Fo 1+sgn a) 2F(Oo)0>0 f(t)=cos oot 0..0<0 冰 cOS Oot 0 fa(t)=cos ot+jsin ot=e/oo FOot <>2兀o(0-0 0 斛析性 单边性*.解析信号 ^ f (t) f (t) f (t) a = + F () = F() + j[− jsgn]F() = F()(1+ sgn) a = 0...... 0 2 ( )... 0    F   t t f t f t t 0 ^ 0 cos 1 ( ) ( ) cos    =  = 2 ( ) ( ) cos sin 0 0 0 0 0          − = + = j t j t a e f t t j t e 解析性 单边性