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Hi
Hongemi,
In
tables 308b/c/d there is a mistake in the description, it should have been as in
table
308 in the 802.16d: "
Number of data subcarriers in each symbol per subchannel" which has no ambiguity.
48 subcarriers in a sunchannel, but for PUSC there are
24 subcarriers allocated per OFDMA
symbol
(over 2 symbols gives you
48).
Regards,
Yossi
From: owner-stds-802-16@listserv.ieee.org [mailto:owner-stds-802-16@listserv.ieee.org] On Behalf Of Sun, Hongmei Sent: Thursday, November 04, 2004 11:43 AM To: STDS-802-16@listserv.ieee.org Subject: Re: [STDS-802-16] Regarding Band AMC--Mapping Dear Panyuh Joo:
Thank you so much for you reply.
For AMC, I think I'm quite clear now.
For
DL PUSC, I think I can understand your meaning, but I do think
description of Spec is confusing.
For
example, in Table 308b, Table 308c and Table 308d of 802.16e/D4 (page 145~146),
there is one row: "Number of
carriers per subchannel: 24 "
So
doesn't that mean in DL PUSC, the each subchannel is composed of 24
subcarrier ?
But
in the other hand, in DL PUSC, 2 cluster makes 1 subchannel, but 1 cluster=12
subcarrier X 2 sym, right,
so
from this point, 1 subchannel has 48 subcarrier totally.
No
matter what this makes reader confusing at its first reading.
I
think the spec doesn't not explicitly seperate these 2 cases, whether the
subcarrier is counted focusing on freq. domain only, or countered by
taking both time domain and freq. domain altogether.
Hongmei SUN
From: owner-stds-802-16@listserv.ieee.org [mailto:owner-stds-802-16@listserv.ieee.org] On Behalf Of Panyuh Joo Sent: Wednesday, November 03, 2004 4:15 PM To: STDS-802-16@listserv.ieee.org Subject: Re: [STDS-802-16] Regarding Band AMC--Mapping Dear Hongmei
Sun, The reason of the following description exist is for
easier understanding the concept to the band. “AMC subchannel consists of 6 contiguous
bins in a same band." And because the statement does not restrict the use of 6
contiguous bins within one symbol, one may use 4 bin in
first symbol and the other 2 bin in the second symbol. If someone uses the
abbreviation on this structure as “ Maybe the word “contiguous” give some wrong sense of
instincts. If just forget the nuance of the word “contiguous” as continuous in
frequency domain, just read it as Contiguous bin in Band. Then we may bend the
thoughts as well as the words. And also please just do not confuse by the concept of
the Band. It just gives you the concept of the AMC subchannelization. And it is not used for BAND AMC MAPPIING
procedure by itself. The mapping of the data PDU is aligned only with definition
of subchannel. I still do not see any mis-description in the original statement in the
specs. And regarding to the DL PUSC, I think there are some
mis-understanding when you read the spec., it would be
appreciated if you can revisit the spec and read it carefully. I will do it too.
If I found the same problems, I will comeback with the answer. But currently, I
do not found any fault in the spec. Hope this may help U. Panyuh Joo From:
owner-stds-802-16@listserv.ieee.org [mailto:owner-stds-802-16@listserv.ieee.org]
On Behalf Of Sun,
Hongmei Panyuh, sorry, but I'm still
confused about this even after your
explanation. As you said, 4 Bins
make one Band, and 6 Bins make one subchannel. So doesn't this hint
that each AMC subchannel must exist across Band? (My understanding is:
for each subchannel: 4 bins are from 1st Band, the other 2 bins are from
2nd Band. Of course, these 6 bins are contiguous.) In addition,from my
understanding, maybe PUSC DL permutation scheme is an exception case in
aspect of subchannel size, where each subchannel has 24 tones but not 48
tones. Pls feel free to
revise me if my understanding is not right. Hongmei
SUN CTL,
Intel From:
owner-stds-802-16@listserv.ieee.org [mailto:owner-stds-802-16@listserv.ieee.org]
On Behalf Of Panyuh
Joo Hi, Varma and
All, Because one
Band only got 4bins and 4 Bin only can make 32 data subcarriers + 4 pilot
subcarriers. Any subchannel shoud have at least 48 tones(subcarriers), if
we do not restrict the definition of AMC subchannel into one band.
than any AMC subchannel can be exist accross the Band.
So, the
meaning of "AMC subchannel consists
of 6 contiguous bins in a same band" ==>
one AMC subchannel should be confined with in the same band. This definition
would help the system exploits the Multi user diversity.
I hope this explanation would help you.
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