《信号与系统 Signals and Systems》课程教学资料（英文版）lecture 7 The Eigenfunction Property of Complex

Example #2: Frequency selective Filters Filter out signals outside of the frequency range of interest CT owpass filters IH(jo)I Only show amplitude here Stopband Passband Stopband Note for dt DT IH(ej o) H(eju )=H(ej(w+ low frequency frequency 2π 兀 兀

Example #2: Frequency Selective Filters Lowpass Filters: Only show amplitude here. — Filter out signals outside of the frequency range of interest low frequency low frequency

Highpass Filters CT 0 Remember DT J丌7 T= highest frequency in dt H(ej h frequency frequenc 兀 2π 3π

Highpass Filters Remember: high frequency high frequency