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Re: [STDS-802-3-EPOC] Definition of Exclusion Subband



Ed,

               I think the term "null subcarrier" has also been used a lot, and we probably should consider a definition for it, if we are going to use it also.

               I have seen two usages of the term "null subcarrier" and I am not sure if we can a common understanding


*        A subcarrier configured to be unmodulated and its QAM value set to zero (consistent with Exclusion subband definition)

*        A subcarrier that carries no information (as in bit loading) and can change based on channel conditions.  Checking channel conditions may require sending a non-zero QAM value on this subcarrier (inconsistent with Exclusion subband)

Hope that helps.  Something we can also discuss on the call.

Steve

From: Edwin Mallette [mailto:edwin.mallette@xxxxxxxxx]
Sent: Tuesday, April 23, 2013 6:21 AM
To: Shellhammer, Steve; STDS-802-3-EPOC@xxxxxxxxxxxxxxxxx
Subject: Re: [STDS-802-3-EPOC] Definition of Exclusion Subband

Steve,

So we've talked about the exclusion sub band and we've also talked about "null subcarriers."  Could you put this in context for me, what's the difference ?  Is it simply that a null subcarrier is "modulated" but its QAM values is set to 0 while an exclusion sub band is described as below ?

Exclusion Subband: A set of adjacent subcarriers, [m, m+1, m+2, ... m+k-1], which are configure via MDIO to be unmodulated and have their QAM values set to zero

Thanks!

Ed

From: "Shellhammer, Steve" <sshellha@xxxxxxxxxxxxxxxx<mailto:sshellha@xxxxxxxxxxxxxxxx>>
Reply-To: "Shellhammer, Steve" <sshellha@xxxxxxxxxxxxxxxx<mailto:sshellha@xxxxxxxxxxxxxxxx>>
Date: Tuesday, April 23, 2013 10:51 AM
To: <STDS-802-3-EPOC@xxxxxxxxxxxxxxxxx<mailto:STDS-802-3-EPOC@xxxxxxxxxxxxxxxxx>>
Subject: [STDS-802-3-EPOC] Definition of Exclusion Subband

All,

               I agreed to draft a straw man definition of "Exclusion Subband"

               We can discuss, and modify as needed, this definition later today on the RF Spectrum Ad Hoc call.

Steve


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