September 2009 Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs) Submission Title: Comments on merged ETRI, Intel, Samsung, CSUS draft Date Submitted: November 19, 2009 Source: Douglas Castor; Weimin Liu, Samian Kaur [InterDigital Communications, LLC] Address: 781 Third Ave, King of Prussia, PA 19406 Voice:[610-878-7800], FAX: [610-878-7841], E-Mail:[Weimin.Liu;Douglas.Castor;Samian.Kaur@interdigital.com] Re: Merged ETRI, Intel, Samsung, CSUS draft, document 15-09-0786-00-0007 Abstract: <Scheme in draft does not support increasing brightness within active frame > Purpose: <Optimize dimming / data rate> 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. Doug Castor, InterDigital

November 2009 Dimming From section 6.6.2.3 ** Value depends on modulation: 50% for OOK and Manchester, for example Scheme cannot support brightness beyond 50%** within active frame Data modulation cuts brightness in half, adding OFF time further dims Lighting companies will want full range of dimming supported Optimal dimming / data rate solution is to pad transmission duration with either ON or OFF, subject to flicker constraints Idle patterns are used when no data, as shown above Solution Allow ON time as well as OFF (dead) time Compute duration of OFF or ON time as MAC controls frame type (e.g. Visibility, Data, etc.) and its periodicity and duration based on dimming and flicker constraints Td is the period of the data frame. B is the average brightness of the modulation (e.g. 50% for OOK) L is the desired brightness given by the dimmer. Doug Castor, InterDigital

September 2009 Thank You! Doug Castor, InterDigital