Re: [802.19] Request for suggestions to make 19-15-0063 better!
Hi Andrew,
Thanks again for putting together this presentation. I have a comment
regarding the LBT requirements in UL LAA. So far, only LAA DL
transmissions is recommended to use LBT category 4 in 3GPP. For UL, LBT is
recommended, without specifying which category. In fact, it has been the
intention of 3GPP to use different LBT category for UL from DL. In 3GPP TR
36.889, §9, Conclusion:
"Based on the evaluations and findings in Section 8, it is recommended
that the channel access framework defined in section 7.2.1.6 be adopted
for LAA. The channel access framework includes a category 4 LBT scheme
including random backoff and variable contention windows at least for the
downlink data transmissions. It is recommended that the key parameters of
the LBT scheme such as contention windows and defer periods should be
configurable within limits to enable fair coexistence with other
technologies operating in unlicensed spectrum. It is recommended that LAA
supports uplink LBT at the UE. In LAA systems, where the UE¹s uplink
transmissions are controlled by the eNB, the uplink channel access scheme
can be different from the downlink channel access scheme for an LAA SCell."
§7.2.1.6:
"It is recommended that a Category 4 LBT mechanism is the baseline at
least for LAA DL transmission bursts containing PDSCH.
It is recommended that LAA supports uplink LBT at the UE. The UL LBT
scheme can be different from the DL LBT scheme (e.g. by using different
LBT mechanisms or parameters) for example, since the LAA UL is based on
scheduled access which affects a UE¹s channel contention opportunities.
Other considerations motivating a different UL LBT scheme include, but are
not limited to, multiplexing of multiple UEs in a single subframe. The
candidates for DL and UL LBT that have been considered in the study item
for the case where LAA supports both DL and UL transmissions are listed in
Section 8.3.2.2."
3GPP is arguing that LBT category 4 should not be used for UL LAA because
it affects LAA eNB UL scheduling. On the other hands, similar arguments in
favor of an exponential backoff mechanism holds for both UL and DL LAA
transmissions. I recommend to add a proposal that LBT category 4 be
considered for UL LAA as well.
Regards,
Alireza
On 8/2/15, 11:18 PM, "Andrew Myles (amyles)" <amyles@xxxxxxxxx> wrote:
>G'day all
>
>As promised the latest version is at
>https://mentor.ieee.org/802.19/dcn/15/19-15-0063-04-0000-proposal-for-ieee
>-802-submission-to-3gpp.pptx
>
>Comments welcome ... and thanks to all those that have provided comments
>so far. The comments have made the document much better! :)
>
>It is still a little long but it is structured in a way that means it can
>be presented in a time that represents the time available
>
>Andrew
>
>-----Original Message-----
>From: Andrew Myles (amyles)
>Sent: Monday, 3 August 2015 1:11 PM
>To: 'yamadaakira@xxxxxxxxxxxxx'; STDS-802-19@xxxxxxxxxxxxxxxxx
>Subject: RE: [802.19] Request for suggestions to make 19-15-0063 better!
>
>G'day Akira
>
>Done! Thanks for your input
>
>I will upload a new version later today (my time)
>
>Andrew
>
>
>-----Original Message-----
>From: Akira Yamada [mailto:yamadaakira@xxxxxxxxxxxxx]
>Sent: Friday, 31 July 2015 5:41 PM
>To: STDS-802-19@xxxxxxxxxxxxxxxxx; Andrew Myles (amyles)
>Subject: Re: [802.19] Request for suggestions to make 19-15-0063 better!
>
>Dear Andrew-- I appreciate your creating great presentation material for
>the upcoming LAA workshop.
>
>Regarding my comment in the previous teleconference on TxOP duration in
>slide p34, please refer to the Section 4.3.2 in TR36.889-d00. Burst
>transmission duration (=TxOP) in Japanese regulation is limited < 4.0ms,
>to enable co-existance among several systems in 5GHz band. It looks "4ms"
>is the most severe rule compared with other countries.
>That's why 3GPP simulates co-ex using TxOP < 4ms. Then, I would suggst
>change "5ms" to "4ms" in slide P34. Please let me know if there's any
>concern.
>
>Best Regards
>Akira
>
>Akira Yamada
>Research Laboratories, NTT DOCOMO,INC.
>TEL:+81-46-840-3759
>
>
>
>On 2015/07/28 14:00, Andrew Myles (amyles) wrote:
>> G'day all
>>
>> The latest version of the proposed 802 submission to the 3GPP workshop
>> is
>>
>>https://mentor.ieee.org/802.19/dcn/15/19-15-0063-03-0000-proposal-for-iee
>>e-802-submission-to-3gpp.pptx.
>> Thank you to those who provided comments
>>
>> Roger, I will be attending the 802.19 call but may be a couple of
>> minutes late
>>
>> Andrew
>>
>> *From:*Andrew Myles (amyles)
>> *Sent:* Tuesday, 21 July 2015 12:22 PM
>> *To:* STDS-802-19@xxxxxxxxxxxxxxxxx
>> *Subject:* [802.19] Request for suggestions to make 19-15-0063 better!
>>
>> G'day all
>>
>> Last week I presented
>> https://mentor.ieee.org/802.19/dcn/15/19-15-0063-00-0000-proposal-for-
>> ieee-802-submission-to-3gpp.pptx as the basis of a possible submission
>> from IEEE 802 to the 3GPP Workshop at the end of August. Many people
>> provided excellent comments and suggested refinements during the
>> meeting. As requested, some people have sent me their comments via
>> e-mail. However, many have not yet done so. Please send me any
>> comments or suggestions so that I can incorporate them into the next
>> version for discussion at the upcoming
>> 802.19 WG teleconferences. And on that topic, could someone please
>> send out details for the scheduled teleconferences; when, where and how?
>>
>> Steve, the draft minutes are incorrect. The session at which "/Jingyi
>> Zhou and Mingxi Fan presented a Liaison presentation on LTE-U, in
>> document 802.19/15-57r1/." was held on Tuesday, 14 July and not
>> Wednesday, 15 July.
>>
>> Andrew
>>