关于数字信号处理的问题
Acontinuous-timesignalxa(t)iscomposedofalinearcombinationofsinusoidalsignalsoffrequencies250Hz,600Hz,1.1kHz,2.4kHz,and3.8kHz.Thesignalxa(t)issampledata2.0-kHzrate,andthesampledsequenceispassedthroughanideallowpassfilterwithacutofffrequencyof900Hz,generatingacontinuoustimesignalya(t).Whatarethefre-quencycomponentspresentinthereconstructedsignalya(t)?