IEEE DRAFT RECOMMENDED PRACTICE Clause 14: Collaborative Coexistence Mechanism – IEEE and Steve Shellhammer (Symbol Technologies) Jim Lansford, Adrian P Stephens (Mobilian Corporation)

Outline Introduction (5) Collaborative Mechanism (14) (MAC Layer Solution) Simulation Result (4) Conclusion Reference

Introduction (1/5) 4 Task Groups TG1: WPAN/Bluetooth TG2: Coexistence TG3: WPAN High Rate TG4: WPAN Low Rate 1 Public Committee

Introduction (2/5) Scope To develop a recommended practice for an IEEE Wireless Personal Area network that coexists with other selected wireless devices operating in unlicensed frequency bands

Introduction (3/5) Two Categories: Collaborative Mechanism (Collocated) To be defined as a coexistence mechanism where WPAN and WLAN exchange information between one another to minimize mutual interference Non-Collaborative Mechanism No exchange of information is used between two wireless

Introduction (4/5)

Introduction (5/5) Non-collaborative mechanism summary: AFH (Adaptive Frequency Hopping) Adaptive Packet Selection and Scheduling Transmit Power Control / Rate Scaling Collaborative mechanism summary : Per-Transmission Request/Confirm TDMA-Base Mechanism

Collaborative Mechanism Introduction Collaborative Mechanism (14) (MAC Layer Solution) Simulation Result Conclusion Reference

Collaborative Mechanism (1/14) By sharing information between collocated and stacks and locally controlling transmissions to avoid interference No new on-air signaling is required Be interoperable with devices that do not include it

Collaborative Mechanism (2/14) Overall Structure: AWMA Control

Collaborative Mechanism (3/14) AWMA Control Entity AP and master are collocated MEHTA Control Entity STAs and slaves are collocated

Collaborative Mechanism (4/14) Alternating Wireless Medium Access Feature: master and AP should collocated in the same physical unit STAs are synchronized by AP AP should send a physical synchronization signal to master WPAN slavers s ACL data transmission is controlled by master Limitation: Could not support SCO link

Collaborative Mechanism (5/14) AWMA TBTT

Collaborative Mechanism (6/14) Structure of the MEHTA Entity

Collaborative Mechanism (7/14) Known Physical-Layer Characteristic b pass-band hopping pattern Local Activity Local Activity TransmitReceive In-bandOut-of-bandIn-bandOut-of-band Transmit NoneTransmit-Receive or None ReceiveTransmit-Receive or None ReceiveNone

Collaborative Mechanism (8/14) Known States: Current or expected receive and transmit activity Channel number Current State End Time Tx Request State: Packet Type Duration

Collaborative Mechanism (9/14) Known States: Current or expected receive and transmit activity Channel List Duration Time Remaining

Decision Logic for Tx Request

Collaborative Mechanism (11/14) Access Mechanism Effect of Tx Confirm (status=denied) DCFThe denied result appears to be a transient carrier-sense condition that requires a DIFS time to expire before a subsequent transmit request can be made. The denied result has no effect on the contention window (CW) or retry variables because no transmission has occurred. (But its will aggregate collision…) PCF (as CF-pollable STA) No transmission from the STA occurs, and the AP can resume transmission after a PIFS. (But its will cause wasting…) PCF as PCNo transmission from the AP occurs, and the AP can resume transmission after a PIFS.

Decision Logic for Tx Request

Collaborative Mechanism (13/14) Recommended Priority Comparison An ACK MPDU should have a higher priority than all packets An SCO packet should have a higher priority than DATA MPDUs. Other priority comparisons are a implementation-specific

Collaborative Mechanism (14/14) Maintaining QoS A device can optionally monitor QoS by defining metrics (such as PER and delay) Maintaining SCO QoS An implementation can optionally attempt to maintain SCO QoS so as not to exceed some level of SCO packet loss by monitoring the SCO PER and comparing with a threshold. The priority of the SCO packet is increased when the SCO PER is above the threshold.

Simulation Result (4) Introduction Collaborative Mechanism (MAC Layer Solution) Simulation Result Conclusion Reference

Simulation Tool accurately models experimental WLAN / BT performance Experimental Results (1/4)

Conference Room Usage (2/4) Many stations, each with independent piconets Bluetooth speakerphone As before, aggregate throughput is shared among all users Back to Single User Scenario Conference Room Scenario

Office Usage Model (3/4) Cluster of users in cubicles, each of which has an independent piconet Throughput is aggregate throughput measured from Access Point Back to Single User Scenario Office Scenario

Individual User (4/4) BT headset operating from same laptop as Wi- Fi station Individual Scenario

Conclusion Introduction Collaborative Mechanism (MAC Layer Solution) Simulation Result Conclusion Reference

Conclusion The Combination of two proposal should revise to be more meaningful There might be some research topic address to the coexistence issue in the point of view The QoS mechanism under the coexistence condition might be a discussible issue as well.

Reference(1/2) TG2 Submission Matrix IEEE P Doc 01/078r0 TG2 Coexistence Mechanism Summary Matrix IEEE P Doc 01/078r2 IEEE Clause Collaborative Coexistence Mechanism IEEE P Doc 01/340r0 TG2 Mobilian Draft Text IEEE P Doc 01/300r1 Clause Adaptive Frequency Hopping IEEE P Doc 01/366r1

Reference(2/2) Clause 1 - Scope and Purpose IEEE P Doc 01/313r1 Clause Description of the Interference Problem IEEE P Doc 01/314r0 Clause Overview of Coexistence Mechanisms IEEE P Doc 01/363r0 Clause MAC Scheduling Mechanism IEEE P Doc 01/316r0 Collaborative Coexistence Mechanism Submission: META + TDMA IEEE P Doc 01/164r0