2.1 Properties of signal and Noise Time average operator T/2 =lim T/2 Periodic waveform with period To O(1)=(t+0) for all t(2-3) Time average operator for periodic waveform T/2)+ T/2)+a5 2.1 Properties of signal and Noise • Time average operator     (2 -1) 1 lim / 2 / 2 dt T T T T       • Periodic waveform with period T0 ( ) ( ) for all t (2 - 3) T0  t  t  • Time average operator for periodic waveform     (2 - 4) 1 ( / 2) ( / 2) 0 dt T T a T a       