[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: stds-80220-coexistence: RE: Coexistence CG Kick-off

Reza, attached are some of my comments to your original message.


Jim Tomcik

At 06:20 PM 8/1/2003 -0400, Reza Arefi wrote:
Resubmission of the previous message so that it gets into the archives.
-----Original Message-----
From: owner-stds-80220-coexistence@majordomo.ieee.org [mailto:owner-stds-80220-coexistence@majordomo.ieee.org]On Behalf Of Reza Arefi
Sent: Thursday, July 31, 2003 2:22 AM
To: 802. 20 Coex CG (E-mail)
Subject: Coexistence CG Kick-off

Dear Coexistence CG participants,
In its July meeting, 802.20 WG chose to form a Coexistence Correspondence Group to "study and create a consensus recommendation on how to address the issues of coexistence of future 802.20 systems with other wireless technologies deployed in the licensed bands below 3.5 GHz."
There were two contributions on the issue of coexistence presented to the WG.
-         C802.20-03/72, by Reza Arefi
-         C802.20-03/61r1, by Jim Tomcik, Ayman Naguib, and Arak Sutivong
The above two contributions, while consistent on acknowledging the challenges of the task, presented different views on how to address the issue within 802.20. While document 72 asked for a Coexistence Task Group within 802.20 to deal exclusively with the issue in parallel to the air interface work, document 61r1 suggested that the matter should be studied by the entire body in series prior to the air interface work.

Reza, I believe the above statement is somewhat in error.  Document 61r1 suggests that the matter of coexistence should be incorporated into the standards development process, not necessarily "studied in series prior to the air interface work."  This could be accomplished through suitable requirements, or evaluation criteria, so that we have some idea how different technical proposals "stack up" when deployed (for example) adjacent to current systems.
The goal of the CG is to come up with a recommendation on the best way to address coexistence within the WG. The coexistence analyses themselves are outside the scope of the CG and are left to a Coexistence document that 802.20 is likely to produce. Therefore, I see the output of this CG as a concise document (probably one page) that includes a clear recommendation to the WG and the rationale behind that recommendation.

Yes, I think this is what we agreed to do.  The document may as you note be 1 page.
The way I propose to go forward is to have open discussions on the reflector for a while so that we get a sense of the range of opinions and the amount of interest in the subject. I will submit to the group a compilation of all views prior to our first conference call on August 15. I propose the following four specific topics for discussion on the reflector so that we stay focused on what we are chartered to do. Please feel free to choose from the list or suggest other related topics I might have missed.

I may not be able to make the conference call on August 15 due to other commitments.  I will try to get one of our other 802.20 members to attend.
  1. Given the fact that 802.20 will be deployed in licensed bands, does 802.20 WG need to address coexistence or should the matter be left to the regulatory regime in each country?
I don't believe this is a strictly regulatory question - we need to address the effects of a new technology deployed in bands that are currently being used by other technologies.  A good start would be to scope the problem by defining the targetted bands of operation and mode of operation anticipated as of this date.
  1. In case the WG chooses to take up the task, should it create a "Recommended Practice" (one containing the word "should") or a "Guideline" (one containing the word "may")?
I don't believe a separate document is what's needed for coexistence.  Rather we need to define either requirements or evaluation criteria so that coexistence is properly considered as 802.20 considers technology alternatives in building an air interface standard.
  1. What are coexistence related issues that need to be resolved before the work on the air interface could begin?
Some issues to be considered (again, as we develop an air interface) are the impacts of 802.20 technology deployed adjacent to (in frequency) each likely existing technology (I'm thinking primarily mobile wireless, satellite, and GPS).  Co-channel interference impacts remains an open issue.

If FDD and TDD operational bands remain undefined, the work should also take into effect the impacts of TDD in FDD bands, and Vice Versa.

There may be other issues, but these are the initial ones I see.
  1. Should the coexistence work focus on the coexistence of 802.20 TDD and FDD variants as the primary source of interference problems? Or should it focus on coexistence with other systems?
Could you elaborate this a little bit?  I think 802.20 TDD and FDD should be considered as interferers, certainly to other systems.  In addition, the opposite effect - existing systems in adjacent channels impacting 802.20 TDD or FDD is of interest.


Looking forward to your participation.



                James D. Tomcik
                QUALCOMM, Incorporated
                (858) 658-3231 (Voice)
                (619) 890-9537 (Cellular)
                From:  San Diego, CA
                PGP: 5D0F 93A6 E99D 39D8 B024  0A9B 6361 ACE9 202C C780