This preview shows page 1. Sign up to view the full content.
Unformatted text preview: ncation and delay are required for
physical realization. 4.3 Equalization
For many physical channels, such as telephone lines, not only are they bandlimited, but they also
introduce distortions in their passbands. Such a channel can be modeled by an LTI ﬁlter followed by
an AWGN source as shown in Figure 4.7. This is the dispersive channel model we describe before. In
general, ISI is often introduced. For a communication system system employing a linear modulation,
such as BPSK, through a dispersive channel, the whole system can be described the conceptual model
4.8 Wong & Lok: Theory of Digital Communications HT ( f ) Ik 4. ISI & Equalization HC ( f ) HR ( f ) Impulses Decision
every T AWGN Figure 4.8: Continuous-time communication model over a dispersive channel Á and ÀÌ ´ µ, À ´ µ, in Figure 4.8, in which the sequence of information symbols is denoted by
and ÀÊ ´ µ are the transfer functions of the transmission (pulse-shaping) ﬁlter, the dispersive channel and the receiving ﬁlter3 , respectively. The Nyquist condition for no ISI...
View Full Document
This note was uploaded on 12/13/2012 for the course EEL 6535 taught by Professor Shea during the Spring '08 term at University of Florida.
- Spring '08