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RE: stds-802-16: WirelessHUMAN and 802.11a coexistence

In reference to the coexistence between 802.11a (indoor use) and the FWA
HUMAN(outdoor use) comments by Zion, I will like to add that according to a
liaison from ITU-R WP 3M to WP 4A (Doc 3M/Temp/8)
"Based on the new data, WP 3M is currently of the view that the average
building entry(or exit)loss may be an excess of the 10dB assumed by WP 4A.
While losses of 10dB  and even lower are observed for some combinations of
elevation and azimuth angles , the average measured losses tend to be an
excess of 10 dB. An average loss value of 15 dB seems to be more reasonable
based on the limited measured data. It should be noted that large variations
in measured entry loss were observed depending  on receiver location and
local environment,..." 

Considering also that RLAN devices, such as 802.11a are mobile devices with
omni-directional antennas, and that technology tools also exist for further
mitigation of interference from Wireless HUMAN, (e.g., use of Dynamic
Frequency Selection and antenna directivity) RLANs and FWA can coexist in
the U NII bands (e.g., 5.25-5.35 GHz band), and that limiting the U NII to
RLANs will not be making an effective use of a scarce national resource to
achieve the goals of that the FCC aimed at with its U NII Report and Order.

Dr. Demosthenes J. Kostas
Director, Industry Standards
Adaptive Broadband Corporation

3314 Dartmouth Ave
Dallas, TX 75205  USA

tel: 214 520 8411
fax: 214 520 9802

-----Original Message-----
From: zion [mailto:zionh@runcom.co.il]
Sent: Friday, October 13, 2000 5:06 AM
To: 'Roger B. Marks'; stds-802-16@ieee.org
Subject: RE: stds-802-16: WirelessHUMAN report

Dear Roger
I don't understand the 802.11a group, their reaction looks as
misunderstanding of the following points:
a. If 802.11a wants to have a spectrum just for them then they are taking a
risk, someone may decided to treat the band as licensed band, with all the
money involved around that. Some hypothesis: 1) If 802.11a will have the
UNII band then the FCC will be asked by the industry to allocate another
band for HUMAN and other license exempt systems. 2) The FCC can split the
UNII band to two or more groups as well. 3) The FCC will leave the situation
as is. With all the above scenarios I don't see why 802.11a should act
especially against HUMAN.
b. The chance to have the UNII spectrum just for 802.11a currently is very
low. It is anticipated that more proprietary non-coordinated technologies
will jump to that spectrum. The risk is bigger if other standard
technologies will upgrade their frequencies to that band, assuming they will
fulfill the FCC rules (like upgrade of: 802.16.3 or Hiperlan2, FWA < 11 from
ETSI). This other standard technologies may be sold in high quantities and
will occupy the band without any farther coordination.
c. If the 802.11a will stop HUMAN to develop under IEEE, it will not prevent
other HUMAN like systems to come from outside IEEE (we can see that from the
number of participation in the HUMAN study group, even if it runs in
parallel to 802.16.3). If 802.11a did not developed for environment like the
UNII is defined today then they should modify it.
d. In case where HUMAN standard will develop under the 802's wings, some
coexistent and coordination with 802.11a can be achieved (using the same
spectral shape, bandwidth, center frequency etc).
e. HUMAN made a call that was pushed by Naftali Chayat from 802.11a to
802.11a for help regarding the adaptation of 802.11a. Our technical
decisions have been taken during the meeting on the reaction to that call
and a full consideration of the 802.11a has been taken.
f. Human decided to choose to be close to 802.11a Phy in order to use the
same spectrum mask, power level, etc... for coexistence reasons and time to
g. Human decided to choose to be close to 802.16.1 MAC in order to take the
ACCESS and other advantages, the group has some freedom in the convergence
MAC/PHY that may be developed for the HUMAN specific needs, where farther
coexistence consideration will be taken. After all, The HUMAN group wants to
share the spectrum with 802.11a with minimum mutual interferences.
h. Effort for HUMAN survival in the UNII band in outdoor environment under
the FCC rules will be taken. Human understand the fact that UNII band may
have other non coordinated technologies in that band, HUMAN may incorporate
farther tools for reducing the mutual interference like APC, highly
directional antennas where LOS condition exists, strong or optimize FEC in
order to minimize the usage of ARQ transmissions in order to prevent farther
possible interferences from HUMAN to the other systems, which will lead to
less retransmission on the other systems, etc...
i. Mutual interference consideration:
802.11a was designed for indoor LAN  for short rang (250 m) and most of the
time the terminal need low transmit power in order to be received correctly
by the receiver, this means that the 802.11a has power margin against
interferences in addition to the building power penetration from outside
interference. The HUMAN RF path propagate throw outdoor environment can
transmit the same maximum radiated power but need to go for longer ranges
(~5-10 Km). If one will make the calculations he will fined that the 802.11a
doesn't have to be afraid from HUMAN that used similar RF parameters.

Best Regards,

Zion Hadad

President and CEO
Runcom Technologies LTD.
Broadband Wireless Technologies DVB-RCT, LMDS, MMDS
Tel: 972-3-9528440 ext. 102   Fax: 972-3-9528805
14 Levi Moshe st. 75158, Rishon Lezion, Israel

-----Original Message-----
From: owner-stds-802-16@ieee.org [mailto:owner-stds-802-16@ieee.org] On Beha
lf Of Roger B. Marks
Sent: Wednesday, October 11, 2000 10:54 PM
To: stds-802-16@ieee.org
Subject: stds-802-16: Wireless HUMAN report

Here is a report on the status of and plans for Wireless HUMAN:

*I submitted the PAR:

        <http://ieee802.org/16/human/par.html> or

to the 802 Executive Committee on time. I have also arranged to get
it on the agenda of the IEEE-SA Standards Board for possible approval
on December 7, provided that 802 approves on November 9.

*The PAR has led to some strong reactions from people in 802.11. Some
have voiced strong opposition; others have suggested placing the work
under 802.11. I have collected the comments together and posted them:


*Based on this reaction, we are planning a Monday evening (6
November, 8:00-9:30 pm) discussion on "Implications of the proposed
Wireless HUMAN PAR on the 802 wireless program." The abstract is
below; the full description (with hardly any more detail) is at:


We originally discussed holding this session on Tuesday, but it was
moved to Monday so that it will assist the other Working Groups in
drafting their comments on the PAR (these are due to us by 5 pm on

*Notice that the session is rather ill-defined. I would like to have
some speakers presenting the thoughts from an 802.16 perspective on
the issues in the abstract. If you would like to be one of those
speakers, let Durga <mailto:durga.satapathy@mail.sprint.com> and me
know. We need to have some people doing some serious preparation for
this session. Otherwise, I am afraid the current PAR will be in

*During Session #10, the WirelessHUMAN Study Group needs to focus on
the following:
   -Mon afternoon and up to 8 pm: organizing itself for the evening session
   -Mon 8-9:30 pm: advocating a position and looking for common ground
   -Tue: discussing reactions to the meeting and developing a revised
   -Tue at 5 pm: distributing comments received by other WGs
   -Wed by 4 pm: preparing response to comments of other WGs
   -Wed by 4:30 pm: getting WG to approve revised PAR at WG Midweek Plenary
   -Wed by 5:00 pm: getting revised PAR into boxes of 802 ExCom members
   -Thu before 3 pm: preparing Call For Proposals as described in PAR
   -Thu 3-5 pm: getting plans approved at Closing Plenary
   -Thu night: attending 802 ExCom meeting during WirelessHUMAN motion




"Implications of the proposed WirelessHUMAN PAR on the 802 wireless program"


This meeting, organized with a more interactive format than a
traditional tutorial, covers the implications of 802.16's proposed
Wireless High-Speed Unlicensed Metropolitan Area Network
(WirelessHUMAN) PAR <http://ieee802.org/16/human/par> on 802's
wireless program. The WirelessHUMAN PAR targets operation in the
unlicensed bands between 5 and 6 GHz, where 802.11 already supports a
physical layer and 802.15 may be considering operation. While the
draft PAR proposes a PHY based on 802.11a, the intent is to base the
MAC on 802.16, which the Study Group believes is more suitable.
Questions to be addressed include:

* Can we identify a prescription to ensure that WirelessHUMAN systems, as
described in the draft PAR, can coexist with nearby 802.11a systems?
* If not, should 802 reject the WirelessHUMAN PAR, and what will be the
* Would it be wise to radically transform the WirelessHUMAN PAR?
* Is there a procedural mechanism to ensure that the WirelessHUMAN standard
development accounts for the interests of 802.11 (and possibly 802.15)