1. Doc: IEEE 802.15-15-0395-00-0008 Submission May 2015 Hernandez,Li,Dotlić,Miura (NICT)Slide 1 Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs) Submission Title: [ Distributed scheduling for CFP ] Date Submitted: [May 12th, 2015] Source: [Marco Hernandez, Huan-Bang Li, Igor Dotlić, Ryu Miura ] Company: [NICT] Address: [3-4 Hikarino-oka, Yokosuka, 239-0847, Japan] Voice:[+81 46-847-5439] Fax: [+81 46-847-5431] E-Mail:[] Re: [In response to call for technical contributions to TG8] Abstract:[ ] Purpose:[Material for discussion in 802.15.8 TG] Notice:This document has been prepared to assist the IEEE P802.15. It is offered as a basis for discussion and is not binding on the contributing individual(s) or organization(s). The material in this document is subject to change in form and content after further study. The contributor(s) reserve(s) the right to add, amend or withdraw material contained herein. Release:The contributor acknowledges and accepts that this contribution becomes the property of IEEE and may be made publicly available by P802.15.

2. Doc: IEEE 802.15-15-0395-00-0008 Submission Distributed scheduling for CFP The CFP means synchronous time-slotted resources for communication links. –GTS in 15.4 parlance. –In most commercial wireless systems, a central unit controls the scheduling [assignment] of resources for such central unit to have communication links with other nodes under diverse criteria. In PAC, there is not central unit: it means PDs, already discovered and peered in a group, need to organize how they will use synchronous time-slotted resources for communication links. May 2015 Hernandez,Li,Dotlić,Miura (NICT)Slide 2

3. Doc: IEEE 802.15-15-0395-00-0008 Submission Distributed scheduling for CFP In other words, PDs need to be aware of the presence of other PDs. –Scheduling decisions are done by everybody. –As such, PDs need to know which PDs have a communication link to avoid collision and interference, and what resources are still available. –Constrain: half duplex (PDs cannot Tx and Rx simultaneously). Our solution: a [tone] [ReS] matrix. –A tone represents the presence of a PD and its signal strength. –Matrix is divided in 2 for Tx and Rx: 1 st block some PDs Tx and others Rx. During the 2 nd block they switch from Tx to Rx and vice versa. May 2015 Hernandez,Li,Dotlić,Miura (NICT)Slide 3

4. Doc: IEEE 802.15-15-0395-00-0008 Submission Distributed scheduling for CFP –PDs in Tx mode send a RTS in a given tone in the 1 st block. PDs in Rx mode listen to the 1 st block. –PDs in Rx mode (during the 1 st block) that accept a communication link, send a CTS in the same tone position in the 2 nd block: PDs in Tx mode (during the 1 st block) send data in the CFP (communication links are scheduled). May 2015 Hernandez,Li,Dotlić,Miura (NICT)Slide 4

5. Doc: IEEE 802.15-15-0395-00-0008 Submission Distributed scheduling for CFP Introducing a priority ID system: PDs in Tx mode send RTS in a given tone in the 1 st block. PDs in Rx mode listen to the 1 st block: –If a PD detects a RTS signal from higher priority or SINR<β, then it refrains from sending a CTS signal in the 2 nd block. –Otherwise, a PD sends CTS signal (power ≈ RTS). PDs in Tx mode in the 1 st block, listen during the 2 nd block: –If a PD detects a CTS signal from higher priority or SINR<β, then it refrains from sending data in the current frame. –Otherwise, a PD sends data in the current frame in the CFP. May 2015 Hernandez,Li,Dotlić,Miura (NICT)Slide 5

6. Doc: IEEE 802.15-15-0395-00-0008 Submission Distributed scheduling for CFP For an accurate estimation of SINR, a pilot signal is sent by all scheduled PDs in Tx mode in the 1 st block. The estimated SINR (for PDs in Rx mode during the 1 st block) is used to choose the modulation and coding rate scheme for the communication link, which is sent as CQI feedback by PDs in Rx mode in the 1 st block. May 2015 Hernandez,Li,Dotlić,Miura (NICT)Slide 6

7. Doc: IEEE 802.15-15-0395-00-0008 Submission Distributed scheduling for CFP Due to the half duplex constrain, a communication link between 2 PDs have 2 links: forward and reverse. –Forward: PD 1 transmits and PD 2 receives. –Reverse: PD 1 receives and PD 2 transmits. Because either PD 1 or PD 2 can initiate a request to transmit, there are 2 tone matrices for PDs in Tx mode and 1 tone matrix for PDs in Rx mode. –If both PD 1 and PD 2 request to be scheduled, the conflict is resolved by alternating priorities. May 2015 Hernandez,Li,Dotlić,Miura (NICT)Slide 7

8. Doc: IEEE 802.15-15-0395-00-0008 Submission Distributed scheduling for CFP May 2015 Hernandez,Li,Dotlić,Miura (NICT)Slide 8

9. Doc: IEEE 802.15-15-0395-00-0008 Submission Distributed scheduling for CFP Preliminary conclusions: –The proposed scheme is fully distributed. –No issue with hidden terminals. –When the number of PDs increases, the tone matrix increases and the scheduling task may take time. –Regardless of the scheduling technique, even centralized ones, when the number of PDs increases, the scheduling task takes longer time. May 2015 Hernandez,Li,Dotlić,Miura (NICT)Slide 9

10. Doc: IEEE 802.15-15-0395-00-0008 Submission Preliminary scheduling response May 2015 Hernandez,Li,Dotlić,Miura (NICT)Slide 10

11. Doc: IEEE 802.15-15-0395-00-0008 Submission Preliminary scheduling response May 2015 Hernandez,Li,Dotlić,Miura (NICT)Slide 11