8()==+=01+0)+m2sm(一) a,+a, cos(o-o =Ot+o(t)+arcti V(t)sin((t)-0() A+v(t)cos(e(t)(t)) 当A>>V(t)大信噪比时 v(t) y(tt+o(t)+sin(e(t)-(t)) A 解调器的输出电压Vo(t)应与输入信号的瞬时频偏成正比 v0(z)=1ry( 2元dt I rdo(t) + 2n dt 2zc{()sine()-9(t)]} 1818 ( ) ( ) 1 3 t t t  = = + = c + cos( ) sin( ) 1 2 2 1 2 2 1     + − − + a a a arctg t (t) = c + ( )cos( ( ) ( )) ( )sin( ( ) ( )) A V t t t V t t t arctg     + − − + 当 A V(t) 大信噪比时 sin( ( ) ( )) ( ) ( ) ( ) t t A V t t t t   c + +  − 解调器的输出电压V0（t）应与输入信号的瞬时频偏成正比 c f dt d t v t = ]− ( ) [ 2 1 ( ) 0   { ( )sin[ ( ) ( )]} 2 1 ] ( ) [ 2 1 V t t t dt d dt A d t      = + −