doc.: IEEE Submission November 2003, Slide 1 Project: IEEE P Working Group for Wireless Personal Area Networks (WPANs) Submission Title: [UWB MAC considerations for Mobile Environment] Date Submitted: [12 th November, 2003] Source: [Juha Salokannel, Pekka A. Ranta (presentator)] Company [Nokia] [Ulrico Celentano] Company [Center for Wireless Communications, Oulu] Address [Itämerenkatu 11-13, Helsinki, Finland] Voice:[ ], FAX: [ ], Re: [ First version from September IEEE /368r0 ] Abstract:[ Presentation enlightens a few possible MAC enhancements for mobile devices ] Purpose:[ For discussion to initiate a few 15.3 MAC layer modifications especially beneficial for mobile devices ] 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.: IEEE Submission November 2003, Slide 2 UWB MAC Considerations for Mobile Phone Environment a/b for Mobile Phone Environment

doc.: IEEE Submission November 2003, Slide 3 Two Fundamentals for Mobile devices: –Most devices are battery powered (power consumption is an issue) –Ad hoc networks are dynamic – devices come and go, but the show must go on. PNC ?

doc.: IEEE Submission November 2003, Slide 4 Battery Consumption in a/b Network An UWB network may consist of devices none of which has fixed power supply. PNC role is the most consuming role. =>Battery level should be taken into account in PNC handover decision PNC PNC Handover command “ Not me! ”

doc.: IEEE Submission November 2003, Slide 5 Battery Level Indication - Definition In the current version of the standard, there is the PSRC bit (“set to one if the DEV is receiving power from the alternating current mains”) Simple (but still effective) way to have an indicator for battery level is to enhance the PSRC bit with one bit. There would be four values reported (as in the table two slides further). More bits may be used for having a larger scale. Battery level is not easy to define absolutely as –devices may have different battery capacities –power consumption may vary with different speed.

doc.: IEEE Submission November 2003, Slide 6 Battery Level Indication - Delivery This info would be given first time among other capabilities in Association Request (overall capabilities). The information could be updated more frequently than at association time, by using PNC Information Request and corresponding response messages. –The PNC information (dev->pnc) can be sent as a response to a request or unsolicited. This is important to support battery level information In the current version of the standard, PNC and DEV Capabilities are exchanged at the association time but cannot be changed after association.

doc.: IEEE Submission November 2003, Slide 7 Battery Level Indication - Interpretation PSTATresid. energystatusinterpretation 11-fixed power supplyPNC role always possible 10> 50 %battery almost fullPNC role now possible 0110 < 50 %battery halfPNC role not desirable 00< 10 %battery almost emptyPNC role ”not possible” In the second column is reported the recommended residual energy levels that the DEV may use. DEV whose battery level is changing, should send an unsolicited response. In the rightmost column it is reported how the PNC handover algorithm should interpret the responses received by DEVs.

doc.: IEEE Submission November 2003, Slide 8 Rebuilding of a/b network in case of broken connections to PNC –High speed recovery may be vital for many applications Use (relative) location as one criteria for choosing PNC? Dynamic Ad Hoc Network PNC ? ? ?

doc.: IEEE Submission November 2003, Slide 9 Other Possible Questions Memory requirements –connected to cost and size (what actually does the PNC role require?) Quaranteed Latency (when having longer superframes) Location Discovery Multicast acknowledgements Need for Handover?