RE: OMA vs. OMA/2 poll
All -
I prefer "a" (OMA) for the reasons I cited earlier. They are more or less
repeated below.
Tom Lindsay
Stratos
1. OMA has already been established and is well understood in Fibre channel
and HIPPI. (OMA/2 is not used).
2. OMA represents the contrast between logic 0 and 1, which is directly what
matters.
3. OMA is simpler to explain, visualize, and implement (such as on a scope.
Finding toplines and baselines are easier than finding a waveform midpoint).
4. Some may think they can relate and therefore measure OMA/2 with average
power on a power meter. Because of the loose control on extinction ratio,
the two values can be quite different. We should not encourage any attempts
at such a relationship.
5. We must be consistent throughout the optical link. That is, use the same
definitions and units at the transmitter as we use at the receiver, etc.
-----Original Message-----
From: David Kabal
To: stds-802-3-hssg-serialpmd@xxxxxxxx
Sent: 4/20/2001 2:09 PM
Subject: OMA vs. OMA/2 poll
Serial PMDers:
I volunteered to set up an informal poll (based on the lack of
participation
at the last Serial PMD conference call: we lacked quorum) on whether to
specify in Clause 52, for example, Receive Sensitivity for each of the
PMDs,
in OMA or OMA/2.
Background:
Originally, all values in the tables and receive sensitivity were OMA/2.
As
of D3.0, we voted to change everything to OMA, but the triple trade off
tables still have both OMA and OMA/2 values listed.
Discussion:
There has been some discussion on this on the reflector, see thread:
http://www.ieee802.org/3/10G_study/public/serial_adhoc/email/msg00228.ht
ml
I propose that we have a single solution for all instances in Clause 52.
a) specify everything in OMA
b) specifiy everything in OMA/2
c) specify everything in both (very difficult to read)
Please post your comments and input to the reflector.
Cheers,
Dave
------
David Kabal
Picolight
Phone: 303-530-3189 ext. 272
Fax: 303-527-4968