Presentation on theme: "A Method for Data Transmission Protection on the IEEE 802.11ac MU-MIMO Downlink Haiguang Wang, Jaya Shankar, Zhongding Lei."— Presentation transcript:
A Method for Data Transmission Protection on the IEEE ac MU-MIMO Downlink Haiguang Wang, Jaya Shankar, Zhongding Lei
Content Background Protect Data Transmission on IEEE ac MU-MIMO downlink Summary
IEEE ac IEEE ac focus on high speed data transmission –Transmission speed up to 1 Gbps –Radio bandwidth up to 160 MHz –Use MU-MIMO technology With MU-MIMO technology, AP can transmit multiple data packets to multiple stations at the same time.
Issues with MU-MIMO Technology One of the problems with MU-MIMO technology is how to protect data transmission. –IEEE use contention-based data transmission. –Legacy RTS/CTS can only provide partial protection over the MU-MIMO downlink transmission. –Collision may happen when legacy stations is hidden to ac stations. AP1 STA2 STA3 STA1 AP2 STA4 RTS CTS Collision MU-MIMO Downlink RTS protection range CTS protection range
Possible Transmission Protection for ac MU-MIMO Downlink A few schemes can be used for transmission protection of ac MU- MIMO downlink, they are: –Legacy RTS/CTS –Single RTS Multiple CTS –Multiple RTS Multiple CTS
Single RTS Multiple CTS (1)
Single RTS Multiple CTS (2) We can also consider to send CTS at the same time. RTS xIFS time AP STA1 STA2 STA3 CTS xIFS time NAV protection NAV distributing CTS xIFS time
Addressing Multiple Stations in RTS Single RTS multiple CTS can provide a better protection on data transmission than legacy RTS/CTS scheme. However, we need solve following issues: –Address multiple stations in RTS. –Compatible with legacy stations
Group Address IEEE ac task group has defined a group ID at PHY layer. A group of stations may be assigned to the same group ID, which indicates that data transmitted in the packet are sent to the stations in this group. Group ID is sent in PHY layer
Using RTS-to-Self and Group ID for Addressing AP uses group ID directly as group MAC address. –To avoid confusion caused by station with MAC address that is equivalent to a group ID, we propose to use RTS-To-Self with group ID in TA field. AP1 STA2 STA3 STA1 AP2 STA4 RTS
Advantage Simple in the implementation. Save the signaling exchange for group addressing. Compatible with legacy system
Summary In this proposal, we have propose a solution for IEEE ac standard in addressing multiple stations with a single RTS packet. The solution is compatible to legacy stations. We have also proposed solutions that may encounter in designing of Single RTS Multiple CTS.