Re: [802.15_GENERAL] TGn Letter Ballot Support
At 11:01 AM 5/27/2008 -0400, Steve Whitesell
wrote:
Hi Steve S
I don't believe I am still on the 802.19 reflector since I had to drop
out
of 802 participation last year, but I appreciate your including me on
the
cc list. I have read and generally agree with the comments form
Ivan Reede
and Carl Stevenson, among others, who oppose allowing 802.11n devices
to
operate with 40 MHz bandwith in the 2.4 GHz ISM band. They
correctly point
out that the provision of a magic "Intollerance Bit" in the
802.11 protocol
is virtually useless for legacy 802.11 devices, other 802 devices that
use
different protocols and/or lower power, and other users of the band such
as
cordless telephones.
While the Part 15 usage of the 2.4 GHz band is on a "must
tolerate
interference received" basis, the FCC has previously shown concern
about
any one device or class of devices becoming a resource hog in the
band.
The 15.247(h) rules for frequency hoppers, for example, prohibits
the
coordination of hop sets among multiple transmitters for the
express
purpose of avoiding simulataneous use of a given hop frequency
while
effectively blanketing the band. That is, one cannot have
multiple
transmitters each using the same pseudo-random hop sequence but starting
on
a different hop frequency in a manner analagous to a "shotgun
start" in
golf wherein 18 foursomes tee-off at the same time, each on a
different
hole. The FCC was aware that such coordination could result in a
class of
products hogging use of the band and prohibited it.
I think the same principle applies to 802.11n devices that would use 40
MHz
in the 2.4 GHz band. They should not be allowed to become a
resource hog
in the band, thereby severely disadvantaging other users. I support
a
modification to the 802.11n standard prohibiting 40 MHz operation
in the
2.4 Ghz band. Lacking that, then I would like to see the FCC take
action.
Regards,
Steve W
"Shellhammer,
Steve"
To: <stds-802-19@ieee.org>,
<bkraemer@marvell.com>,
<sshellha@qualcom
<carl.stevenson@ieee.org>,
<david.cypher@nist.gov>,
m.com>
<eldad.perahia@intel.com>,
<I_reede@amerisys.com>,
<john.barr@motorola.com>,
<Joseph.Levy@InterDigital.com>,
05/25/2008 02:38
<Mark.austin@ofcom.org.uk>,
<mjlynch@nortel.com>,
PM
<nada.golmie@nist.gov>,
<ppiggin@nextwave.com>,
<bheile@ieee.org>, "Shellhammer, Steve"
<sshellha@qualcomm.com>,
<sli@sibeam.com>,
<swhitesell@vtech.ca>,
<vivek.g.gupta@intel.com>
cc: "Paul Nikolich"
<paul.nikolich@att.net>
Subject: RE: [802.15_GENERAL] TGn Letter Ballot
Support
IEEE 802.19 TAG,
Paul
Nikolich would like the opinion of the 802.19 members
on the 40 MHz 802.11n discussion.
If you
have an opinion to share please "reply-all" so that
everyone can hear your opinion.
Regards,
Steve
________________________________
From: Paul Nikolich
[mailto:paul.nikolich@att.net]
Sent: Saturday, May 24, 2008 7:06 AM
To: Shellhammer, Steve
Subject: Fw: [802.15_GENERAL] TGn Letter Ballot Support
Steve,
What is dot19's opinion on the below debate?
--Paul
----- Original Message -----
From: Matthew Fischer
<mailto:mfischer@BROADCOM.COM>
To: STDS-802-WPAN@LISTSERV.IEEE.ORG
Sent: Friday, May 23, 2008 10:29 PM
Subject: Re: [802.15_GENERAL] TGn Letter Ballot Support
I will be voting YES on TGn LB129, and I would urge others who are
interested in defending 802.15.x devices' access to the ISMii band
to
vote YES as well.
The current draft of the 802.11 TGn amendment contains normative
language describing a mechanism (i.e. the 40 MHz Intolerant bit)
that
allows non-related devices to signal to the 40 MHz TGn devices that
they
cannot send 40 MHz transmissions, effectively allowing other users
of
the ISMii band to restrict the use of 40 MHz transmissions by TGn
devices. 40 MHz 802.11 TGn devices are required to obey this
signaling
whenever it occurs.
If 40 MHz operation is forbidden in ISMii by 802.11 TGn, then 40
MHz
operation will be implemented as a set of vendor-specific
non-standardized modes with variable degrees of good citizenship
regarding spectrum sharing and with little or no opportunity for
such
devices to be controled by other users of the ISMii band.
For these reasons, it is in the best interest of 802.15.x
technology
providers and other users of the ISMii band to vote YES on the
TGn-standardized mode of 40 MHz operation that includes specific
requirements to force TGn devices to cease 40 MHz operation when
requested.
Matthew Fischer
Nice Guy
+1 408 543 3370 office
+1 650 796 9206 mobile
mfischer@broadcom.com
<mailto:mfischer@broadcom.com>
________________________________
From: John Barr
[mailto:john.barr@MOTOROLA.COM]
Sent: Friday, May 23, 2008 8:36 AM
To: STDS-802-WPAN@LISTSERV.IEEE.ORG
Subject: [802.15_GENERAL] TGn Letter
Ballot Support
As mentioned in Jacksonville, the current
draft of TGn includes
use of 40 MHz channels in 2.4 GHz spectrum. This will significantly
impair ability of other IEEE standards using 2.4 GHz spectrum to
coexist
with TGn devices running at 40 MHz. Even though the rejection of my
comment number 6069 states that there is provision for coexistence
with
other radio systems using 2.4 GHz spectrum, the actual text for this
is
informative and does not actually include tests for IEEE 802.15.1
nor
IEEE 802.15.4 devices. See attached note to TGn I sent during the
Jacksonville meeting. At the one session where there was any
discussion
on my comment, I spoke against the resolution and no one spoke for
the
resolution rejecting my suggested change (not to allow any use of 40
MHz
channels in 2.4 GHz spectrum). (See attached)
As it current stands there is no clear
method to prevent use of
40 MHz channels in 2.4 GHz when IEEE 802.15.1 and 802.15.4 devices
are
operating in the same spectrum.
You can vote against the current TGn
letter ballot by
referencing my comment (6069) that is unresolved (not accepted by
the
submitter) and requesting the same resolution: In 20.3.15 change
"When
using 40 MHz channels, it can operate in the channels defined in
20.3.15.1 and 20.3.15.2." to "When using 40 MHz channels, it
can only
operate in the channels defined in 20.3.15.2."
James Gilb may be able to clarify just how
to vote on this.
Voters who previously approved the original LB can change their vote
to
disapprove based on this comment.
Thank you for your support.
Regards, John
--
John R. Barr
(John.Barr@Motorola.com)
Director, Standards Realization -
<http://www.motorola.com>
<http://www.motorola.com>
Vice Chairman of the Board, Bluetooth SIG
-
<http://www.bluetooth.org>
<http://www.bluetooth.org>
(847) 576-8706 (office) +1-847-962-5407
(mobile) (847) 576-6758
(FAX)
(See attached file: C.htm)
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Bob Heile, Ph.D
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Chair, IEEE 802.15 Working Group on Wireless Personal Area Networks
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