Discrete-Time Signals. Time-Domain Representation Unit of sampling frequency is cycles per second, or Hertz(hz), if T is in seconds Whether or not the sequence xn has been obtained by sampling, the quantity xn] is called the n-th sample of the sequence Cin] is a real sequence, if the n-th sample xn is real for all values of n Otherwise, x[n is a complex sequence Copyright C 2001, S K Mitra7 Copyright © 2001, S. K. Mitra Discrete-Time Signals: Time-Domain Representation • Unit of sampling frequency is cycles per second, or Hertz (Hz), if T is in seconds • Whether or not the sequence {x[n]} has been obtained by sampling, the quantity x[n] is called the n-th sample of the sequence • {x[n]} is a real sequence, if the n-th sample x[n] is real for all values of n • Otherwise, {x[n]} is a complex sequence