Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs)

1. Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs) Submission Title: [TG4 Coexistence Considerations] Date Submitted: [22 January 2002] Source: [Robert Poor] Company [Ember Corporation] Address [1 Broadway, 14th Floor / Cambridge MA 02142 USA] Voice:[617 758-4262], FAX: [617 758-4101], E-Mail:[robert.poor@ember.com] Re: [] Abstract: [General description of TG4 position with regard to Coexistence] Purpose: [This document outlines the position of TG4 with regard to Coexistence and proposes further steps to be taken by TG4 and TG2 towards a succesful standard.] 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. Robert Poor, Ember Corporation

2. TG4 Coexistence Considerations Dallas 802.11 Interim Meeting January, 2001 Robert Poor, Ember Corporation

3. Current Position From section 7.5.1 (CSMA): All devices shall use the radio channel in such a way as not to obstruct the transmissions of other devices, which may already be transmitting. Robert Poor, Ember Corporation

4. Goals Today: • Introduce 802.15.4. coexistence work to date • Form TG2/TG4 liaison team Near-future: • Harmonize language in specification • Joint white paper • OpNet simulation Robert Poor, Ember Corporation

5. About 802.15.4 IEEE 802.15.4 is… a standard for low complexity, low cost, low power consumption and low data rate wireless connectivity among inexpensive devices. The raw data rate is high enough to satisfy a set of simple needs such as interactive toys and human interface devices, but scalable down to the needs of industrial, agricultural, medical, and vehicular applications. Robert Poor, Ember Corporation

6. Schedule & Goals • January: Letter Ballot (passed with 650 comments) • March: Recirculation Ballot Approved • April: SDL and PICS completed • May: Sponsor Ballot Approved Robert Poor, Ember Corporation

7. 2.4GHz PHY overview PHY as ‘good citizen’: • Low Power: variable: must be capable of -3dBm, upper bound set by regulatory limits • Efficient Encoding: DSSS MSK: 2MCps, 250Kbps, 62.5KSps (4 bits/Symbol) • Frequency Agile: 2.4-2.4835GHz in 16 channels with 5MHz spacing (and 5 more channels in 915 MHz band) • Controlled bandwidth: -20dB and -30dBm@ f0±2.5MHz Robert Poor, Ember Corporation

8. MAC overview MAC as ‘good citizen’: • CSMA: with exponential backoff (except for ACKs) • CCA: using energy threshold and/or carrier sense (as in 802.11) • Low Duty Cycle: Anticipated less than 1%, greater than 12% difficult • Short Packets: Maximum length 58 bytes (1.86 mS) Robert Poor, Ember Corporation

9. Coexistance Team For efficient inter-group communications: • Steve Shellhammer (TG2) • Nada Golmie (TG2) • Robert Poor (TG4) Robert Poor, Ember Corporation

10. Questions? Robert Poor <r@ember.com> Robert Poor, Ember Corporation