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Re: [STDS-802-16] Clarification on OFDMA subcarriers allocation and BTC in RevD4



[This email was intended for the reflector, but it bounced because it
was addressed to <owner-stds-802-16@LISTSERV.IEEE.ORG>. Please stick
with <stds-802-16@ieee.org>.   -Roger]

Hi, Yossi,

Thanks a lot for your rapid response, especially in the weekend.

But I have a few more questions:
1. In the 4th paragraph of 8.4.4.2, there is a sentense "In PUSC, the FCH is
transmitted using QPSK rate 1/2 with two repetitions using the mandatory
coding scheme"; In the first paragraph of 8.4.4.5, the modulation of FCH
seems to be changed as "QPSK with coding rate 1/2 and repetition coding of
4".  Which is true?
2. I can't find the modulation scheme for DL MAP and UL MAP in the RevD4. Is
it mandatory scheme? Does the std. need to specify it clearly?
3. In the 8.4.5.4.8 about FAST_FEEDBACK channels, there are totally 96 bits
to transmit, why "A fast feedback slot uses QPSK modulation on the 96
sub-carriers it contains"? Are 48 subcarriers not enough?

Thanks again in advance
Jun Wu
ZTE San Diego

-----Original Message-----
From: Yossi Segal [mailto:yossis@runcom.co.il]
Sent: 2004ŸÍ4'¬10»' 17:41
To: 'Jun Wu'
Cc: owner-stds-802-16@listserv.ieee.org
Subject: RE: [STDS-802-16] Clarification on OFDMA subcarriers allocation
and BTC in RevD4


Hi Jun,

1. Number of data subcarriers is 48 (I shall fix the error in the table)
2. This is a mistake number of clusters are doubled to get 120 (I shall fix
this too)
3. Coding rates in the table does not compute to exactly 1/2, but are used
when 1/2 code rate should be used. The data amount transferred was derived
from a good performing code (which does not compute nicely to rate 1/2).

Thank you for pointing these out.

Regards,

Yossi

-----Original Message-----
From: owner-stds-802-16@listserv.ieee.org
[mailto:owner-stds-802-16@listserv.ieee.org]On Behalf Of Jun Wu
Sent: Saturday, April 10, 2004 23:22
To: STDS-802-16@listserv.ieee.org
Subject: [STDS-802-16] Clarification on OFDMA subcarriers allocation and BTC
in RevD4


I have several questions about UL and DL subcarriers allocation. Does anyone
have a good answer?
1. In the Table 273, row 7 indicates "Nsubcarriers 24", row 9 indicates
"Numbers of data subcarriers per subchannel 48", what is the difference
between them? Which value (24 or 48) should be used to calculate the
subcarriers(n,s) in equation 102.
2. In the 8.4.6.1.2.2.1 step 1, there are totally 120 clusters, they are
divided into 6 major groups, but the 6 groups have only 60 clusters. Can
anyone clarify this?

The third question is about BTC:
3. In the Table 282, the second column should be "Encoding rate R=1/2",  but
I found the coding rate of most case is not 1/2. Does anyone can explain
this?

Thanks in advance for your response.
Jun Wu
ZTE San Diego