d-R(=8(t ●单边指数信号f(t)=Aelu(t)=Ael(t) t=T f()=Ae=0.3684 双边指数信号f()=Aeah=Ae ●复指数信号f(t)=Ae=Ae0 2. s=0 f(0=Ae 3. S=J@ f(t)=Ae/= a(cos ot+jsin ot) 4、s=σ+jiof(1)= allots=Ae( cos ot+ isin a) sin t Sa(t) f(t) Sa(t) 偶函数 lim f(t)=lim ont t→0 3.当t=kz(k=士1±2+3…)时,f()==0 4. lim f(t)= lim sin t 信号的时域分解 1.分解成无穷多个阶跃的连续和( ) ( ) 2 2 t dt d R t =  ⚫ 单边指数信号 ( ) ( ) ( ) 1 f t Ae u t Ae u t t  t  − − = = t f (t) Ae 0.368A 1 1 = = = = −   ⚫ 双边指数信号 t t f t Ae Ae   1 ( ) − − = = ⚫ 复指数信号 st j t f t Ae Ae ( ) ( )  +  = = 1. s = 0 f (t) = A 2. t s f t Ae =  ( ) = 3. s j f (t) Ae A(cos t jsin t) j t     = = = + 4、 ( ) (cos sin ) ( ) s j f t Ae Ae t i t j t t        = + = = + + ⚫ Sa(t) ( ) sin ( ) Sa t t t f t = = 1. 偶函数 2. 1 sin lim ( ) lim 0 0 = = → → t t f t t t 3. 当 t = k (k = 1,2,3) 时， 0 sin ( ) = = t t f t 4. 0 sin lim ( ) = lim = →  →  t t f t t t 5. =    − dt t sin t 二、信号的时域分解 1. 分解成无穷多个阶跃的连续和