1. doc.: IEEE 802.11-11/0142r0 Submission January 2011 Nir Shapira, Celeno Communications DL MU-MIMO Support for non-AP STAs Date: 2011-01-18 Authors: Slide 1

2. doc.: IEEE 802.11-11/0142r0 Submission January 2011 Nir Shapira, Celeno Communications Abstract Transmit DL MU-MIMO functionality is currently defined for AP only [1]. We show use cases for extending DL MU-MIMO capability to non-AP STAs Reference [1] suggested a robust scheme for MU group management by using Unicast messaging We suggest a method for enabling DL MU-MIMO beamformer capabilities to STAs, based on the mechanism suggested in [1], such that no extra burden is placed on beamformees Slide 2

3. doc.: IEEE 802.11-11/0142r0 Submission January 2011 Nir Shapira, Celeno Communications Motivation Network topologies are becoming more complex –Multimedia home network – a point to multi-point non-AP media streamer –Mesh networks: each node routes information for multiple other nodes –IPTV use case: MRDVR as a second multi stream source –Wifi Direct: each STA can assume the role of a “soft AP” In many cases same chipset used for both AP and STA. –MU-MIMO capability is already there, STA might as well use it Traditionally in 802.11, physical layer capabilities were common to AP and STA. DL MU-MIMO should not be an exception Slide 3

4. doc.: IEEE 802.11-11/0142r0 Submission Regional Gateway acts as AP (broadband entry point) DVR second source for multiple streams January 2011 Nir Shapira, Celeno Communications Use case example – Multi Room DVR Multi-room DVR STB RG (AP) STB STB WiFi Ethernet dongle Time shifted Linear Laptop iPad Broadband Network Slide 4

5. doc.: IEEE 802.11-11/0142r0 Submission January 2011 Nir Shapira, Celeno Communications Proposal guidelines Physical layer mechanism is identical to that suggested for the AP –Use of DL MU-MIMO (DL from the perspective of the station) –This solution has nothing to do with the UL MU-MIMO concept that was not accepted for 11ac Based on the robust GroupID mechanism accepted in [1] No extra complexities for beamformees Maintain current maximum of 64 group indices AP is the sole initiator of GroupID management frames Slide 5

6. doc.: IEEE 802.11-11/0142r0 Submission January 2011 Nir Shapira, Celeno Communications Proposal details A STA that would like to form a MU group will ask the AP to establish the group Once established, using GroupID protocol as in [1], the AP will notify the requesting STA of the new GroupID index –In case group already existing, AP just notifies the requesting STA on group index From that moment, both AP and any other requesting station can use DL MU-MIMO to the MU group in question Beamformees completely agnostic to identity of beamformers Slide 6

7. doc.: IEEE 802.11-11/0142r0 Submission January 2011 Nir Shapira, Celeno Communications Proposal details – cont’ In case AP changes definition of a group used by another BFer, it first needs to notify the BFer to cease use of group AP can answer with “unable to comply” to a group- forming request from STAs Non-AP STA would need to get a list of AIDs for all its intended beamformees to be able to send NDPA. AID protocol distribution is TBD Beamformee needs to “know” identity of BFer –Needed to verify NDPA is not from OBSS –Identity can be pre-established using DLS –Otherwise, BSSID should be added to NDPA Slide 7

8. doc.: IEEE 802.11-11/0142r0 Submission January 2011 Nir Shapira, Celeno Communications Summary The case was made for enabling MU-MIMO transmit capability in non-AP STAs Advanced use cases require advanced transmit functionality in STAs The presented solution keeps the AP in control as the only entity that sends GroupID management frames No extra burden is placed on beamformees Exact protocol for request/grant of Mu group is TBD and requires further investigation Slide 8

9. doc.: IEEE 802.11-11/0142r0 Submission January 2011 Nir Shapira, Celeno Communications References [1] Sameer Vermani, et. al., Frame Format for GroupID management, TGac, IEEE 802.11-10/1288r0 Slide 9

10. doc.: IEEE 802.11-11/0142r0 Submission January 2011 Nir Shapira, Celeno Communications Straw Poll 1 Do you agree DL MU-MIMO capability for non-AP STAs is beneficial for TGac and is worth further investigation? Slide 10

11. doc.: IEEE 802.11-11/0142r0 Submission January 2011 Nir Shapira, Celeno Communications Straw Poll 2 Do you agree that the general concept of DL MU-MIMO for non-AP STAs outlined in this submission, wherein: -The AP is the only entity that sends GroupID management frames -Other non-AP STAs can request the AP to form MU groups -AP and other non-AP STAs can use the same MU group indices to perform DL MU-MIMO transmissions Is a good basis on top of which a comprehensive solution should be further investigated? Slide 11