Page 246 - Anatomy of a Robot

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COMMUNICATIONS 231

Intersymbol Interference
FIGURE 9-3 A poor receive filter enables consecutive pulses to interfere
with each other.

All pulses cross 0 at decision time.
FIGURE 9-4 A good raised cosine receive filter makes consecutive pulses
cooperate.

received pulse signals, even though they have oscillations in their leading and trailing
edge, cross zero just when the samples are taken. That way, adjacent pulses do not inter-
fere with one another (see Figure 9-4).
The following sites discuss the RCF:
www.iowegian.com/rcfilt.htm
www-users.cs.york.ac.uk/ fisher/mkfilter/racos.html
www.ittc.ukans.edu/ rvc/documents/rcdes.pdf
www.nuhertz.com/filter/raised.html

COMMON BASEBAND COMMUNICATION STANDARDS

The following are some relatively common wired baseband communication links that
we all have used. These are communication links that have relatively few wires and are