tailieunhanh - Lecture Digital communication systems - Lecture 16

The following will be discussed in this chapter: The press, the law, and the courts; protecting news sources; covering the courts; reporters’ access to information; defamation; invasion of privacy; copyright; obscenity and pornography; regulating broadcasting; regulating cable TV; the telecommunications act of 1996; regulating advertising. | ffl 00 00 oo 00 00 00 00 00 00 INTRODUCTION TO EECS II DIGITAL COMMUNICATION SUSTEMS Fall 2012 Lecture 16 DTFT vs DTFS Modulation Demodulation Frequency Division Multiplexing FdM Fall 2012 Lecture 16 Slide 1 Fast Fourier Transform FFT to compute samples of the DTFT for signals of finite duration For an x n that is zero outside of the interval 0 L-1 choose P L with P preferably a power of 2 we ll assume that it s at least a multiple of 2 . even P-1 P 2 -1 X Qk 2 x m e a x n -1 2 X Qk j m 0 P k -P 2 where Qk k 2n P and k ranges from -P 2 to P 2 -1 or over any P successive integers. Simpler notation X Qk Xk Fall 2012 Lecture 16 Slide 2 Where do the Qk live . for P 6 even Fall 2012 Lecture 16 Slide