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Dear Bin,
Thanks for your reply. The referenced proposal
was adopted during 3GPP RAN2 #70 without objection. Please note that
the C-RNTI(which is similar to STID in 16m) is 16-bit long, it is preferable to
keep the capacity of 802.16p standard comparable to that of LTE MTC.
Best Regards,
Yi-Ting
From: Bin Chen
Sent: Friday, February 11, 2011 3:56 PM
Subject: Re: [STDS-802-16] [802.16p][DEV-RG] - Email Discussion on
M2M device identification Hi, Yi
Ting, Thanks for your sharing.
I agree with you on the SRD
text. May I ask a question that
whether 3GPP standard group adopt your proposal about 30000 devices a cell? How
did they think about it? I think that may be a reference
for us. BR/Bin From: 林奕廷 (Lin, Yi-Ting)
[mailto:eating@NMI.III.ORG.TW] Dear Hyunjeong and
all, Thanks for your question. Yes,
I think 16p system should support 30000 M2M devices in connected
state. In SRD 6.2.9, it says
"The 802.16p
system shall support large numbers of M2M devices in connected state as well as
in idle state." Unfortunately, it is
not clear how "large" should be. We provide the value of 30000 by our
experience. I also agree with you that 1000 devices could be burden for 16m/16e
base station, but I don't agree 1000 is "large". I believe this discussion is to
seek consensus on the number of connected devices. If people
think 30000 is too large, I appreciate they could provide their suggestions.
Best Regards, Yi-Ting From: Hyunjeong Kang
Sent: Friday, February 11,
2011 1:27 PM Subject: RE: [STDS-802-16]
[802.16p][DEV-RG] - Email Discussion on M2M device
identification Dear Yi-Ting
and all, Yi-Ting,
Thank you for
your information. I have a
question based on Yi-Ting’s information. I understand
there are more than 30,000 M2M devices in a cell, but I wonder it is feasible to
assume that 30,000 M2M devices are in connected state. Because we are discussing
the addressing space to be used in connected state. Do you think
that 30,000 M2M devices stay in communication mode with a base
station? In my thought,
it is too burden for a base station to manage more than 1,000 devices in
connected state. Regards, Hyunjeong From: 林奕廷 (Lin, Yi-Ting)
[mailto:eating@NMI.III.ORG.TW] Dear
all, Thanks for Chiwoo's
analyses. We agree that, with current 16m feedback channel design, the
maximum number of devices would be 12032. We would like to
share our experiences on smart meters in Taipei. Please refer to the
file <http://www.3gpp.org/ftp/tsg_ran/WG2_RL2/TSGR2_70/Docs/R2-103269.zip> for
reference. For a cell of 1 km radius, the number of smart meters could be
more than 30000. In practice it is not likely all smart meters attach
to the network at the same time. But, considering various M2M
applications would run simultaneously in a cell, we think the value
of 30000 is reasonable to be the baseline number of supported
devices. Best
Regards, Yi-Ting From: Lim Chiwoo
Sent: Friday, February 11,
2011 10:08 AM Subject: Re: [STDS-802-16]
[802.16p][DEV-RG] - Email Discussion on M2M device
identification Dear 16p members,
As Kaushik
pointed, we couldn’t agree on how many devices we need to support or how many
devices we can currently support. According to
addressing issue, it’s required to determine this first. I want to show my
calculations about current feedback capacities of 16m and 16e.
I think that the
size of STID doesn’t need to largely exceed the capacity of feedback channel
because operation is not guaranteed if there is no relevant feedback.
The results show
that the number of supportable user based on feedback channel are 7168/12032/200
in cases of 16m(10MHz)/16m(20MHz)/16e(10MHz), respectively.
I think that we
can consider these results when we determine the number of devices to be
supported in M2M. Please let me know
your opinion. Please see
following calculations. Basic conditions
-
DL:UL
= 5:3 -
One
feedback channel makes 6 HARQ feedback channels. -
Maximum number of
LRUs for feedback channel : 16 (4 bits indication) -
Maximum number of
HARQ feedback channel is 30/60 for 10/20MHz, respectively.
-
Let’s
consider maximum HARQ feedback channel. -
The
report period of fast feedback channel is up to 128 frames (=640ms, 3 bits
indication) -
<10MHz case,
16m> There is a
restriction of number of feedback channel. The MAX number is 27.
(per one subframe) 5 feedback
channels are used for HARQ feedback channels. (per one DL subframe (one HARQ
feedback region)) There are 81 (= 27
* 3) feedback channels per one frame. 25 (=5*5) feedback
channels are used for HARQ feedback channel. That is, there are
56 fast feedback channels in a frame. When we consider
the report period as 8/32/128 frames, the number of supportable user are
448/1792/7168. <20MHz case,
16m> There are 48
feedback channels. (per one subframe) 10 feedback
channels are used for HARQ feedback channels. (per one DL subframe (one HARQ
feedback region)) There are 144 (=
48 * 3) feedback channels per one frame. 50 (=10*5)
feedback channels are used for HARQ feedback channel. That is, there are
94 fast feedback channels in a frame. When we consider
the report period as 8/32/128 frames, the number of supportable user are
752/3008/12032. <10MHz case,
16e> In 16e, the report
period of CQICH channel is up to 8 frames (= 40ms, 2bits indication)
There are 35
subchannels per one frame in 10MHz. 6 subchannel shall
be used as ranging channel. Therefore, if we
assume 25 subchannels for CQICH and 4 subchannels for ACK/NAK, the number
of supportable user is just 200. BR,
Chiwoo From: Kaushik Josiam
[mailto:kjosiam@STA.SAMSUNG.COM] Dear 16p
members In the DEV RG
conference call today, we wanted to hear the member’s view on how many devices
we need to support in 802.16p systems. We can increase the addressing
space to support a large number of users, but in the conference call, we
couldn’t agree on how many devices we need to support or how many devices we can
currently support. Related to this
issue, do we need to define a new M2M specific IDs for M2M devices?
If you have any
thoughts or proposals on the issue, please share them as a reply to this
thread. We thank you for
your cooperation. Regards Kaushik &
Ming-Hung DEV RG
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