[802.3ae_Serial] Jitter experiments

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This email is in response to my committment on the 11/27/01 serial PMD con-call. This is still very crude, and I apologize for lack of appropriate thought, but hopefully it can stimulate more discussion.

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A major concern for 10G serial is instrumentation error for doing jitter measurements. Steve's Buchheit's work clearly demonstrates this. Ideally, instrumentation will improve sufficiently to allay this concern, but none of us expect that to occur sufficiently in advance of deployment. So if we are to keep the basic definition and method for jitter measurement, then we require agreed upon means to compensate the instrumentation.

With this in mind, I simply brainstormed 5 categories of test settings and measurements, with the hopes (dreams?) that differences in their results can provide insight into how compensation can be achieved.

1. Measuring instruments

Scope - eye patterns w/ crossing histograms

Error detector - jitter bathtub

2. Configurations (essentially the same used by Steve)

Pattern generator to measuring instrument

Pattern generator through E/O and O/E to measuring instrument

Pattern generator through stress conditioning and E/O and O/E to measuring instrument

Pattern generator through DUT and O/E to measuring instrument

3. Test patterns

At this point, I do not know if there is a path through this that will lead anywhere (this is the apology again...). I hope someone else can determine if there is really any value in here. The 5-dimensional matrix results in a large number of test combinations - too many. A Design of Experiments may be required to reduce the set. Obviously more directed experiments can be defined with some risk of missing key information.