Re: Frequency Spectrum
any signal can be represented as weighted sums of sinusoids(shifted if necessary)....
sinusoid is chosen in particular because it has some amazing properties....All linear
operations(addition , multiplication , differentiation , integration ,etc) on a sine function results in another sine function ( shifted or scaled,etc)...so now wat happens is tat
all the complex operations like differentiation ,etc just reduced to addition ,etc..
It even becomes simple when u change sin(w*t)---> Real part of { exp(jwt) }.
So we just need to know wat will happen if a sinusoid of some frequency goes thro a system ..it will get shifted and scaled ..the former called phase and latter called magnitude...