doc.: b Submission Mar Song-Lin Young[Sharp Labs.] Slide 1 Project: IEEE P Working Group for Wireless Personal Area Networks (WPANs) Submission Title: [CTA Advertisement for Overlapping Piconets] Date Submitted: [Mar. 2004] Source: [Song-Lin Young] Company [Sharp Labs. of America, Inc.] Address [5750 NW Pacific Rim Blvd, Camas, WA, 98607] Voice:[ ], FAX: [ ], Re: [ b-SG3b-Closing-Report-Jan04.ppt] Abstract:[This document provides the method for announcement of CTA by non-PNC devices to uncoordinated piconet.] Purpose:[This contribution is a response to SG3b call for submission about proposed amendment of MAC Standard.] Notice:This document has been prepared to assist the IEEE P 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 P

doc.: b Submission Mar Song-Lin Young[Sharp Labs.] Slide 2 CTA Advertisement for Overlapping Piconets Song-Lin Young Sharp Labs. of America, Inc.

doc.: b Submission Mar Song-Lin Young[Sharp Labs.] Slide 3 Contents Introduction Issues associated with PNC/beacon CTA announcement mechanism Conclusions and future work

doc.: b Submission Mar Song-Lin Young[Sharp Labs.] Slide 4 Introduction Operations of 15.3 WPAN require devices to find a PNC (and its beacons) in order to engage in piconet activities. Multiple piconet overlapping scenarios are expected to occur in a dynamic environment, such as home networking. –Device may start a piconet without knowing the existence of a nearby PNC. –Piconet consisting of portable devices may be carried around and brought into area of other piconets. –Changes of topology due to moving objects/people

doc.: b Submission Mar Song-Lin Young[Sharp Labs.] Slide 5 Simple Piconet Configuration PNC Device 1 Beacon Device 2 Beacon CTA 1 CTA 2 CTA 1 Superframe NSuperframe N+1 Beacon CTA 2 PNC 1 Device 1 Device 2

doc.: b Submission Mar Song-Lin Young[Sharp Labs.] Slide 6 Overlapping Piconets PNC 1 Device 1 PNC 2 Beacon PNC Device 1 PNC 2 Beacon Device 2 A.PNC 2 is not able to hear beacons form PNC 1 B.Device 2 is not able to hear beacons from PNC 1

doc.: b Submission Mar Song-Lin Young[Sharp Labs.] Slide 7 Potential Interference Scenario CTA Superframe Beacon PNC 1 Device 1 PNC 2 or Device 2 Interference Device 1 (PNC 1) is scheduled to transmit during the assigned CTA(s) PNC 2/Device 2 will be interfered during Device 1 CTA if two piconets are not coordinated

doc.: b Submission Mar Song-Lin Young[Sharp Labs.] Slide 8 Basic Concept A mechanism is needed to advertise piconet timing and CTA for those unassociated devices not covered by PNC Extending the coverage area of beacons such that superframe timing and CTA information is available for: –Making it possible for devices to be aware of existing piconets via scan operation. –Better selection of channel/frequency usage. –Co-existence by sharing channel time

doc.: b Submission Mar Song-Lin Young[Sharp Labs.] Slide 9 Beacon Frame Format PreambleHeader Superframe Duration CTA # 1 CTA # 2CTA # 3CTA # n FCS p0 (Superframe starts) Dev A Address Dev B Address Stream Index CTA Duration CTA Location

doc.: b Submission Mar Song-Lin Young[Sharp Labs.] Slide 10 Quasi-Beacon Frame Format During transmission, the device advertises its CTA(s) containing duration and offset from beginning of superframe Only corresponding CTA of transmitting device are advertised. Superframe duration can also be included. Applicable to Data, command, and Ack frame types. Superframe Duration CTA # nFrame Control PreambleHeaderDataFCS p0 (Packet starts) HCS

doc.: b Submission Mar Song-Lin Young[Sharp Labs.] Slide 11 Conclusions CTA Advertisement Solve hidden node problem Facilitate the following operations: –Coexistence of multiple piconets –Coordination/synchronization of piconets –Device discovery Minimum overhead to each packet

doc.: b Submission Mar Song-Lin Young[Sharp Labs.] Slide 12 Future Work Asymmetric data transfer –Delay Ack frames which occur less frequently Streaming applications –No Ack frame