Thread Links Date Links
Thread Prev Thread Next Thread Index Date Prev Date Next Date Index

[802.3ae] Clause 52 - receiver bandwidth measurement




Dear 802.3ae,

In draft 3.2, Table 52.9, page 438, titled "10GBASE-S" receive
characteristics, it lists Receive electrical 3 dB upper cutoff frequency
(max) = 12.3 Ghz.  I can measure this parameter easily when there is no
clock and data recovery.   Does anyone have an idea how to measure this
parameter given that most of these transceivers have clock and data
recovery and will not run much above or below 10.3125 Gb/s?

The same goes for Table 52.14, page 440, titled "10GBASE-L receive
characteristics".

This spec should be required, as laser relaxation oscillation in a direct
modulated laser and could have 100% overshoot for instance with the
frequency of oscillation > 12 Ghz.  You want the receiver to act as a
filter and this has to be normative.  Are you implying we should just
guarantee this by design even though we can not test it at the module
level?

Kevin Demsky
Integration Team Lead
IBM Corp.
3605 Hwy 52 N
Dept. QXS Bldg. 040-2
Rochester, MN  55901

E-mail:  kdemsky@us.ibm.com

Phone:  507-253-5799
Fax:  507-253-1438