Basic TGad MAC Layer Proposals and Options for Coexistence January 2010 doc.: IEEE 802.11-xx/xxx1r0 Basic TGad MAC Layer Proposals and Options for Coexistence Date: 2010-03-15 Authors: Name Affiliations Address Phone email David Tung Chong Wong Institute for Infocomm Research (I2R), A*STAR 1 Fusionopolis Way, #21-01 Connexis, Singapore 65-6408-2258 wongtc@i2r.a-star.edu.sg Xiaoming Peng I2R, A*STAR Same as above 65-6408-2429 pengxm@i2r.a-star.edu.sg Francois Chin 65-6408-2530 chinfrancois@i2r.a-star.edu.sg Xuhong Qu 65-6408-2477 quxh@i2r.a-star.edu.sg Raymond Jararaj s/o Jayabal 65-6408-2226 jraymond@i2r.a-star.edu.sg David Wong, I2R

January 2010 doc.: IEEE 802.11-xx/xxx1r0 Abstract Propose two basic MAC layer superframe structures for Infrastructure Basic Service Set (BSS) operations and Ad Hoc Independent BSS (IBSS or PBSS) operations, and include options for coexistence when another 60GHz network comes into the TGad network. The goal is to allow the TGad network to detect this other 60 GHz network using a multi-directional quiet periods and to report the sensing outcomes by the stations through directional mini-slots or through directional EDCA MAC or directional HCCA MAC or through a directional CSMA/CA MAC in multiple directions and to move to another band so as to avoid interference between the two systems. David Wong, I2R

Basic TGad MAC Layer Proposal with Options for Coexistence We first propose two basic MAC layer superframe structures for Infrastructure BSS operations and Ad Hoc IBSS (or PBSS) operations. We then add options for coexistence when TGad network and another 60 GHz network, both in operations (not the case when one TGad network starts up), come into contact. These options for coexistence allow the TGad network to detect the other 60 GHz network and allow the TGad network to make detection decision through data fusion rules like OR-fusion rule, AND-fusion rule OR Majority fusion rule, for the detection of the other 60 GHz network.

Infrastructure BSS AP Stations Sector 1 Sector 2 Sector 3 Sector n Figure 1 – AP with stations having n directions

Basic TGad MAC Layer - Proposal 1 … Beacon interval n-1 Beacon interval n Beacon interval n+1 … Quasi-omni Beacon Period Association CP (A-CP) CFP and regular sub-CP (RS-CP) in Direction #1 … CFP and regular sub-CP (RS-CP) in Direction #n Dir. #1 … Dir. #n AS-CP for Dir. #1 … AS-CP for Dir. #n CFP for Dir. #1 RS-CP for Dir. #1 … CFP for Dir. #n RS-CP for Dir. #n Can also have alternating RS-CPs and RS-CAPs using directional EDCA and HCCA MACs, respectively Can also have alternating RS-CPs and RS-CAPs using directional EDCA and HCCA MACs, respectively Association Sub-CPs Broadcast and multicast frames Broadcast and multicast frames RS-CP for Dir. #1 – using directional CSMA/CA EDCA MAC RS-CAP for Dir. #1 - using directional HCCA MAC … RS-CP for Dir. #n – using directional CSMA/CA EDCA MAC RS-CAP for Dir. #n - using directional HCCA MAC … Regular sub-CP(s) with EDCA-TXOPs and Regular sub-CAP(s) with HCCA-TXOPs Regular sub-CP(s) with EDCA-TXOPs and Regular sub-CAP(s) with HCCA-TXOPs Figure 2 – Proposed Basic MAC Layer Beacon Interval Structure 1

Basic TGad MAC Layer - Proposal 1 (1) In the beacon, it is divided into three sections: quasi-omni beacon section, AP quasi-omni tracking section and sector training section. In the first section, beaconing is supported by transmitting the beacon frame in the different directions. Direction refers to an antenna direction or an array pattern. The second section allows devices in the infrastructure BSS to track the AP quasi-omni directions. The third section enables pro-active beam forming.

Basic TGad MAC Layer - Proposal 1 (2) The association contention period (A-CP) is used for devices to send association request commands to the AP, while the contention-free periods (CFPs) are used for broadcast or multicast packets and the regular sub-contention periods (RS-CPs) are used for all other commands and data exchanges. The CFP and RS-CP is divided according to the different directions. For the CFP after the A-CP, broadcast and multicast frames can be transmitted directionally.

Basic TGad MAC Layer - Proposal 1 (3) Transmission in the RS-CP is done using CSMA/CA in a directional manner, similar to IEEE 802.11e EDCA MAC with four access categories, and there is a period before the end of the RS-CP that must be considered before transmitting a packet. For the regular sub-contention periods (RS-CPs), a directional enhanced distributed channel access (EDCA) CSMA/CA MAC can be used. For the contention free period (CFP) at the end of the superframe, a polling MAC like HCF controlled channel access (HCCA) can be used directionally.

Basic TGad MAC Layer - Proposal 1 (4) For regular sub-controlled access phase (RS-CAPs) in the RS-CPs, HCCA MAC can be used directionally. EDCA MAC is the enhanced CSMA/CA MAC of distributed coordination function (DCF) MAC, while HCCA MAC is the enhanced polling MAC of point coordination function (PCF) MAC. EDCA MAC and HCCA MAC are the CSMA/CA MAC and the polling MAC, respectively, of IEEE 802.11e MAC. IEEE 802.11e allows for Quality of Service (QoS) for four access categories (ACs).

Basic TGad MAC Layer - Proposal 1 (5) EDCA MAC uses AIFSs, CWmin[AC], CWmax[AC] and transmit opportunities (TXOPs), where AC can be background, best effort, video and voice traffic. HCCA MAC uses PIFS, QoS polling and HCCA (polled) TXOPs.

Basic TGad MAC Layer – Proposal 2 (1) … Beacon interval n-1 Beacon interval n Beacon interval n+1 … Quasi-omni Beacon Period Contention Period (Any Directional CSMA/CA MAC) Dir. #1 … Dir. #n Figure 3 – Proposed Basic MAC Layer Beacon Interval Structure 2

Basic TGad MAC Layer – Proposal 2 (2) Here, any of the directional CSMA/CA MAC in IEEE 802.11-09/0796r0 can be used in the contention period.

Options for Coexistence in Proposal 1 (1) Quasi-omni Beacon Period CFP and regular sub-CP (RS-CP) in Direction #1 Association CP (A-CP) Beacon interval n Beacon interval n+1 Beacon interval n-1 … Dir. #1 Dir. #n RS-CAP for Dir. #1 - using directional HCCA MAC AS-CP for Dir. #1 AS-CP for Dir. #n RS-CP for Dir. #1 – using directional CSMA/CA EDCA MAC Association Sub-CPs CFP and regular sub-CP (RS-CP) in Direction #n RS-CP for Dir. #n – using directional CSMA/CA EDCA MAC RS-CAP for Dir. #n - using directional HCCA MAC RS-CP for Dir. #1 CFP for Dir. #1 CFP for Dir. #n RS-CP for Dir. #n Regular sub-CP(s) with EDCA-TXOPs and Regular sub-CAP(s) with HCCA-TXOPs Broadcast and multicast frames Can also have alternating RS- CPs and RS-CAPs using directional EDCA and HCCA MACs, respectively. Can also have alternating RS-CPs and RS-CAPs using directional EDCA and HCCA MACs, respectively. Station #1 sensingreport Quasi-omni Quiet Period Quasi-omni Reporting Period Station #m sensingreport Mini-slots for sensing reports by all stations in direction #1. Figure 4 – Option 1 for coexistence in MAC Proposal 1

Options for Coexistence in Proposal 1 (2) Figure 5 – Example of the directions of each station for collaborative multi-direction sensing in the quiet period

Options for Coexistence in Proposal 1 (3) In option 1, the main additions to the basic MAC layer superframe structure are the quasi-omni quiet period and the quasi-omni reporting period. There are multi-quiet periods in the different directions for the AP and stations to sense for the other 60 GHz network, for examples, IEEE 802.15.3c or ECMA-387 network. Each sub-quiet period is used by the AP or station to sense for the other network in their particular direction out of the n possible directions. Note that the initial direction of sensing by each station should be in such a way that all stations in that sector cover different directions.

Options for Coexistence in Proposal 1 (4) This can be assigned to the station by the AP when it associates with the AP. Another way is to use the station’s MAC address and compute it, that is, (MAC address MOD n). Thus, the AP and the stations are sensing collaboratively in multiple directions as whole during the quiet period. There are also multiple mini-slots in the different directions for the stations to report their sensing outcomes.

Options for Coexistence in Proposal 1 (5) The mini-slots in different direction can be dynamically assigned to stations by the AP when the stations associate with the AP in the A-CP and indicated in a new field in the quasi-omni beacon period in that direction. The particular mini-slot for a station will be removed when the station disassociates from the AP. The AP decides if the other 60 GHz network is present or not, based on the data fusion rules like OR-fusion rule, AND-fusion rule or Majority fusion rule.

Options for Coexistence in Proposal 1 (6) … Beacon interval n-1 Beacon interval n Beacon interval n+1 … Quasi-omni Beacon Period Quasi-omni Quiet Period Association CP (A-CP) CFP and regular sub-CP (RS-CP) in Direction #1 … CFP and regular sub-CP (RS-CP) in Direction #n Dir. #1 … Dir. #n Dir. #1 … Dir. #n AS-CP for Dir. #1 … AS-CP for Dir. #n CFP for Dir. #1 RS-CP for Dir. #1 … CFP for Dir. #n RS-CP for Dir. #n Association Sub-CPs Can also have alternating RS- CPs and RS-CAPs using directional EDCA and HCCA MACs, respectively. Can also have alternating RS-CPs and RS-CAPs using directional EDCA and HCCA MACs, respectively. Broadcast and multicast frames Broadcast and multicast frames RS-CP for Dir. #1 – using directional CSMA/CA EDCA MAC RS-CAP for Dir. #1 - using directional HCCA MAC … RS-CP for Dir. #n – using directional CSMA/CA EDCA MAC RS-CAP for Dir. #n - using directional HCCA MAC … Regular sub-CP(s) with EDCA-TXOPs and Regular sub-CAP(s) with HCCA-TXOPs Regular sub-CP(s) with EDCA-TXOPs and Regular sub-CAP(s) with HCCA-TXOPs Figure 6 – Option 2 for coexistence in MAC Proposal 1

Options for Coexistence in Proposal 1 (7) In option 2, the only addition to the basic MAC layer superframe structure is the quasi-omni quiet period. There are multi-quiet periods in the different directions for the AP and stations to sense for the other 60 GHz network as before. However, the stations can report their sensing outcomes to the AP through directional EDCA MAC using CSMA/CA or through directional HCCA MAC in the RS-CAPs for different directions.

Options for Coexistence in Proposal 1 (8) The stations can also send the sensing reports to the AP using directional EDCA MAC in option 2 using high priority like short AIFS and small contention window sizes. Similar to option one, the AP then decides if the other 60 GHz network is present or not, based on the data fusion rules.

Options for Coexistence in Proposal 2 (1) … Beacon interval n-1 Beacon interval n Beacon interval n+1 … Quasi-omni Beacon Period Quasi-omni Quiet Period Quasi-omni Reporting Period Contention Period (Any Directional CSMA/CA MAC) Dir. #1 … Dir. #n Dir. #1 … Dir. #n Dir. #1 … Dir. #n Station #1 sensingreport … Station #m sensingreport Mini-slots for sensing reports by all stations in direction #1. Figure 7 – Option 1 for coexistence in MAC Proposal 2

Options for Coexistence in Proposal 2 (2) This option is similar to option 1 for coexistence in MAC proposal 1, except that the association and setting up of the mini-slot for sensing reporting is done in the contention period using any directional CSMA/CA MAC as in IEEE 802.11-09/0796r0 .

Options for Coexistence in Proposal 2 (3) … Beacon interval n-1 Beacon interval n Beacon interval n+1 … Quasi-omni Beacon Period Quasi-omni Quiet Period Contention Period (Any Directional CSMA/CA MAC) Dir. #1 … Dir. #n Dir. #1 … Dir. #n Figure 8 – Option 2 for coexistence in MAC Proposal 2

Options for Coexistence in Proposal 2 (4) Similarly, this option is similar to option 2 for coexistence in MAC proposal 1, except that data communication and sensing report by the stations to the AP or the station that sends out the beacon target transmission time (TBTT) are done in the contention period using any directional CSMA/CA MAC as in IEEE 802.11-09/0796r0 .

Summary We propose two basic MAC layer superframe structures for Infrastructure BSS operations and Ad Hoc IBSS (PBSS) operations with options for coexistence with another 60 GHz network by detecting it. The TGad network could then move to another band. The options for coexistence cater for the case when the TGad network and another 60 GHz network, both in operations, come into contact. These coexistence options can be used in every beacon interval, or once in a number of beacon intervals. A proposed solution for the case when the TGad network starts up can be found in IEEE 802.11-09/1160r3.

January 2010 doc.: IEEE 802.11-xx/xxx1r0 References 11-09-1160-03-00ad-proposed-evaluation methodology-additions 11-09-0796-00-00contention-based directional MAC protocols: a survey IEEE Std 802.15.3c™-2009 ECMA-387 David Wong, I2R

Straw Poll Do you support inclusion of the technique,     - Options for coexistence as described in 10/0249r0 in the TGad draft amendment? Y: N: A: Slide 27