[SI-LIST] Re: frquency limit of a channel
- From: "Zabinski, Patrick" <zabinski.patrick@xxxxxxxx>
- To: <si-list@xxxxxxxxxxxxx>
- Date: Sun, 7 Mar 2010 07:09:46 -0600
Ah, yes, I was being too simplistic. In simulation, it is possible to
create a sawtooth signal that has a 0% to 100% risetime that approaches
a full bit period.
In the lab/field, though, how realistic is this? With edge rate
typically being defined as 10% to 90% (or even more extreme, 20% to
80%), the effective duration of the signal transition is greater than
indicated by the edge rate number alone. In particular, high frequency
attentuation will roll off the "teeth" (corners) of the signals. When
we account for practical channel effects and how the edge rate accounts
for only a portion of the signal, then what happens?
-----Original Message-----
From: si-list-bounce@xxxxxxxxxxxxx [mailto:si-list-bounce@xxxxxxxxxxxxx]
On Behalf Of LD
Sent: Saturday, March 06, 2010 9:35 PM
To: Lakshmi N. Sundararajan - PTU; si-list@xxxxxxxxxxxxx
Subject: [SI-LIST] Re: frquency limit of a channel
Patrick,
That is not true. If the period is 166ps the rise time needs to be less
than this figure and the fall time has to be less that that period. The
signal will generally need to complete a rise or fall time and stay high
or low for a very small fraction of that time. In fact most good
receivers and recover the data if the rise time where to be 166ps and
the fall time was also 166ps or less and there was zero high or low
time.
------------------------------------------------------------------
To unsubscribe from si-list:
si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field
or to administer your membership from a web page, go to:
//www.freelists.org/webpage/si-list
For help:
si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field
List technical documents are available at:
http://www.si-list.net
List archives are viewable at:
//www.freelists.org/archives/si-list
Old (prior to June 6, 2001) list archives are viewable at:
http://www.qsl.net/wb6tpu
Other related posts:
