MAC Protocol to Support Dynamic Bandwidth for 802.11aj (60GHz) Sept 2012 doc.: IEEE 802.11-012/xxxxr0 July 2013 MAC Protocol to Support Dynamic Bandwidth for 802.11aj (60GHz) Date: 2013-07-17 Presenter: Xiaoming Peng Xiaoming Peng / I2R

Author List July 2013 Xiaoming Peng

July 2013 Abstract This document is to propose a channelization for China 60GHz frequency band for 802.11aj (60GHz) This document is to propose a MAC protocol amendment to support dynamic bandwidth for 802.11aj (60GHz) The proposed MAC protocol supports the backward compatibility with 802.11ad legacy device This contribution has been discussed in CWPAN group Xiaoming Peng

Highlight of The Main Changes July 2013 Highlight of The Main Changes Add Slide 13-14 To support network setup and operation in small band (e.g. Channel 5 or Channel 6) only. Add Slide 15-18 To support interoperability with 11ad legacy devices. Add Slide 22-23 To add two more study cases to support Mixed Mode with 11ad legacy devices. Xiaoming Peng

Background: China 60GHz Spectrum July 2013 The released 60GHz spectrum in China only has 5GHz bandwidth, corresponding to channel 2 & 3 used in IEEE 802.11ad. USA, Canada, Korea Europe China Japan Australia Unlicensed 60 GHz spectrum bands. Xiaoming Peng

Proposed Channelization for 60GHz bands for 802.11aj (1/2) July 2013 Proposed Channelization for 60GHz bands for 802.11aj (1/2) Advantage of the proposed channelization for 60GHz bands in China China only has 5GHz bandwidth available in 59-64GHz  only has two logical channels if only use 2.16 GHz BW Further divide 2.16GHz band used in 802.11ad channelization into two 1.08GHz sub-bands, then it become 6 logical channels: 2 bands with 2.16GHz bandwidth (Channel 2 & 3), 4 bands with 1.08GHz bandwidth (Channel 5, 6, 7, 8)； Channelization for 60GHz bands in China Xiaoming Peng

Proposed Channelization for 60GHz bands for 802.11aj (2/2) July 2013 Proposed Channelization for 60GHz bands for 802.11aj (2/2) Support dynamic bandwidth  Capable of supporting wider applications for lower power, e.g. Smart Phone, Tablet etc. The impact to implementation in RF, Analog baseband is very minimal. It only needs to add to support four more new center frequency in PLL design, a new filter to support 1.08GHz in analog baseband etc； The support of dynamic bandwidth in the channelization for China 60GHz bands provides the basis of keeping the interoperability with 802.11ad device； Channelization for 60GHz bands in China Xiaoming Peng

MAC Protocol: Support Dynamic Bandwidth Sept 2012 doc.: IEEE 802.11-012/xxxxr0 MAC Protocol: Support Dynamic Bandwidth July 2013 Proposed MAC Protocol amendment for 802.11aj: support dynamic bandwidth and keep interoperability with 802.11ad When operating in 2.16GHz channel（Channel 2,3)，it is capable of keeping interoperability with 802.11ad device； When operating in 1.08GHz（Channel 5,6,7,8），it sends common beacon over 2.16GHz channel. The common beacon can use 802.11ad beacon as baseline so that 802.11ad device can also recognize the common beacon; This allows 802.11aj device to keep the interoperability with 802.11ad device while exploring the benefits in channels with 1.08GHz bandwidth. Revised 60GHz Channelization Common Beacon (e.g., 802.11ad DMG Beacon frames) Proposed frame structure for IEEE 802.11aj Xiaoming Peng Xiaoming Peng / I2R

Proposed MAC Protocols (1) Sept 2012 doc.: IEEE 802.11-012/xxxxr0 July 2013 Proposed MAC Protocols (1) Support that PCP/AP 1 operates in Channel 2 with 3 devices (STA 1, STA 2 and STA 3) STA (to become PCP/AP 2) wants to share Channel 2 STA (to become PCP/AP 2) may join PCP/AP 1’s network and send a Channel Split Request frame for the split of Channel 2. Order Information 1 Category 2 DMG Action 3 Dialog Token 4 Channel Switch Announcement element Channel Split Request frame Action field format Xiaoming Peng Xiaoming Peng / I2R

Proposed MAC Protocols (2) Sept 2012 doc.: IEEE 802.11-012/xxxxr0 July 2013 Proposed MAC Protocols (2) If PCP/AP 1 agrees to split Channel 2 PCP/AP 1 replies a Channel Split Response frame to the STA (to become PCP/AP 2). PCP/AP 1 informs other STAs through a Channel Switch Announcement element contained in DMG Beacon/Announce frames . PCP/AP 1 proceeds to split Channel 2 Order Information 1 Category 2 DMG Action 3 Dialog Token 4 Channel Splitting field 5 Beacon Interval field (optional) 6 Channel Switch Announcement element (optional) 7 Extended Schedule element (optional) Channel Split Response frame Action field format Proposed Frame Structure to support Dynamic Bandwidth for 802.11aj Xiaoming Peng Xiaoming Peng / I2R

Proposed MAC Protocols (3) Sept 2012 doc.: IEEE 802.11-012/xxxxr0 July 2013 Proposed MAC Protocols (3) After the split of Channel 2 into Channel 5 and Channel 6, PCP/AP 1 sends out common DMG beacons in Channel 2 during NP1 to announce its operation and shows its channel bandwidth status (using the reserved B45-46 to indicate Channel Bandwidth info) contained in Beacon Interval Control field). Following which PCP/AP 2 (The STA become PCP/AP 2) sends out common DMG beacon in Channel 2 during NP2 to announce its operation and shows its channel bandwidth status . PCP/AP 1 and PCP/AP 2 each creates a quiet period (QP) in their respective networks. PCP/AP 2 synchronizes with PCP/AP 1 by receiving the time stamps in PCP/AP 1’s common DMG beacons in its BTI. Non-AP/non-PCP STAs continue their packet transmissions in small band network in Channel 5 after tuning in and receiving the DMG Beacon frames sent out by PCP/AP 1 in its BTI, coupled with the necessary procedures like beamforming, associations and new schedules for service periods (SPs) and contention-based periods (CBAPs). Non-AP/non-PCP devices STAs that want to join the network in Channel 6 have to tune in and receive DMG Beacon frames sent by PCP/AP 2 in its BTI, coupled with the necessary procedures. Xiaoming Peng Xiaoming Peng / I2R

Proposed MAC Protocols (4) July 2013 Proposed MAC Protocols (4) Constant monitoring of Channel 2 common DMG beacons sent out by PCP/APs 1 and 2 in NP1 and NP2, respectively. Assume Channel 6 ceases its network operation. Absence is noted by PCP/AP 1 when it detects no common DMG beacon frames sent during NP1. PCP/AP 1 shall wait for a aMaxExpireDuration duration before making the decision that Channel 6 network has ceased operation. Case 1: After which, the PCP/AP 1 can proceed to expand its bandwidth from Channel 5 to Channel 2 (see the following figure), or Case 2: After which, the PCP/AP1 can proceed to remain its operation in Channel 5. Xiaoming Peng

Proposed MAC Protocols (5) July 2013 Proposed MAC Protocols (5) Suppose that PCP/AP 1 starts up or operates in the small band, e.g., Channel 5. To mitigate interference, PCP/AP 1 must periodically send notification signals during notification periods (NPs) on Channel 2. Each NP contains at least a beacon header interval (BHI) which may include beacon transmission interval (BTI), association beamforming training (A-BFT) and / or announcement transmission interval (ATI) as shown in the following figure. Xiaoming Peng

Proposed MAC Protocols (6) July 2013 Proposed MAC Protocols (6) Later, a new PCP/AP 2 intends to start its network in the adjacent Channel 6. First, PCP/AP 2 scans the channel to know whether Channel 6 is empty or not. If Channel 6 is available, PCP/AP 2 will send a Channel Request frame to PCP/AP 1 for NP allocation.  PCP/AP 1 may reject the PCP/AP 2 request if another network has been successfully established in Channel 6. Otherwise, PCP/AP 1 should accept PCP/AP 2 request through a Chanel Response frame. PCP/AP 1 shall allocate a pseudo-static SP for the NP of PCP/AP 2 (i.e., BHI 2) on Channel 2 through an Extended Schedule element. Xiaoming Peng

Backward Compatibility of IEEE 802.11aj July 2013 Backward Compatibility of IEEE 802.11aj [3] has described “Backward Compatibility Feature for 802.11aj” Legacy Mode Case 1: An IEEE 802.11ad device scans to find an available large band and starts its network as normal 802.11ad device. Case 2: An IEEE 802.11ad device scans to find an IEEE802.11ad or IEEE 802.11aj network operating in the large band and joins as a non-PCP/non-AP STA. Mixed Mode Support the backward compatibility for IEEE 802.11ad devices when IEEE 802.11aj networks are operating in small bands. Xiaoming Peng

July 2013 Mixed Mode (1/3) Case 1: Suppose that only PCP/AP 1 operates in Channel 5 while Channel 6 is empty. If an 802.11ad legacy device requests to join, 802.11aj PCP/AP 1 may change its channel to Channel 2 first, and then operate like 802.11ad PCP/AP and accept 802.11ad legacy device as non-PCP/AP STA PCP/AP 1 may also decide to operate in Channel 5 and allocate SPs or CBAPs to 802.11ad legacy device in Channel 2 through DMG Beacon or Announce frames as show in the following figure. To distinguish different channel bandwidths, we use the reserved Bit 5 of the Allocation Type field to indicate allocation type, which supports the backward compatibility to IEEE 802.11ad devices. Bit 4 Bit 5 Bit 6 Meaning SP allocation in large band 1 SP allocation in the small band CBAP allocation in large band CBAP allocation in small band All other combinations Reserved Xiaoming Peng

July 2013 Mixed Mode (2/3) Case 2 : Both Channel 5 and 6 are occupied by PCP/AP 1 and PCP/AP2, respectively. Suppose that 11ad legacy STA A intends to join in PCP/AP 1’s network. PCP/AP 1’s allocations for STA A must abide by TWO conditions: No overlaps with the existing allocations either in large band or in small bands. PCP/AP 2 shall avoid to schedule the allocations time-overlapping with that of STA A. The mixed mode works as below: First, PCP/AP 1 shall hear the latest DMG Beacon or Announce frames or directly request PCP/AP 2 to reply with Extended Schedule elements . Second, PCP/AP 1 schedules the allocations for STA A and may notify the result to PCP/AP 2 through an Allocation Request frame. Third, PCP/AP 2 may reply with an Allocation Grant frame to grant this schedule or not. Lastly, PCP/AP 1 sends the schedule result to STA A (and PCP/AP 2) through Extended Scheduling element transmitted in DMG Beacon or Announce frame. Xiaoming Peng

July 2013 Mixed Mode (3/3) Case 3: Suppose that only PCP/AP 1 operates in Channel 5 and has scheduled the allocations for 802.11ad legacy devices within Channel 2. In this case, another PCP/AP 2 that intends to start up will know that Channel 6 is empty. PCP/AP 2 follows the same procedures in Slide 14 to establish its BSS in Channel 6. Since PCP/AP 2 has received the Extended Schedule element through the Beacon/Announce frames transmitted by PCP/AP 1, it will avoid to schedule its SPs or CBAPs that would overlap with the allocations for 802.11ad legacy devices in the following medium time. Xiaoming Peng

Case Study A: Support Dynamic Bandwidth July 2013 Case Study A: Support Dynamic Bandwidth Case A: Two PCP/APs operate in two adjacent small bands within the same large band. Xiaoming Peng

Case Study B: Support Dynamic Bandwidth July 2013 Case Study B: Support Dynamic Bandwidth Case B: Only one PCP/AP operates in a small band when the adjacent small band is unoccupied. Xiaoming Peng

Case Study C: Support Dynamic Bandwidth July 2013 Case Study C: Support Dynamic Bandwidth Case C: Only one PCP/AP operates in a large band when the large band is available. This is similar to 802.11ad Xiaoming Peng

Case Study D: Mixed Mode July 2013 Case Study D: Mixed Mode Case D: Only one PCP/AP operates in a small band when the adjacent small band is unoccupied. In this case, IEEE 802.11ad devices join as non-PCP/non-AP STAs. Xiaoming Peng

Case Study E: Mixed Mode July 2013 Case Study E: Mixed Mode Case E: Two PCP/APs operate in two adjacent small bands within the same large band. In this case, IEEE 802.11ad legacy devices join one of BSSs as non-PCP/non-AP STAs. Xiaoming Peng

July 2013 Conclusion This presentation proposed a channelization for China 60GHz frequency band for 802.11aj (60GHz) This presentation proposed a MAC protocol amendment to support dynamic bandwidth for 802.11aj (60GHz) The proposed MAC protocol supports the backward compatibility with 802.11ad legacy devices Xiaoming Peng

July 2013 Reference [1] 11-12-1197r0 - Physical Channel Consideration for Chinese 60GHz band [2] 11-13-0176r0 - Proposal of Channelization for 802.11aj [3] 11-13-0175r1 - Backward Compatibility Feature for 802.11aj [4] 11-12-0140r9 - IEEE 802.11.aj PAR [5] 11-12-0141r7 - IEEE 802.11.aj 5C Xiaoming Peng

July 2013 Thank YOU Xiaoming Peng