<July 2008> Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs) Submission Title: [Multi preamble to support Single MAC for multi PHY] Date Submitted: [14 July 2008] Source: [H.S.Lee, D. Y. Kim, C. S. Eun, S. M. Ryu] Company [ETRI, Chungnam Univ., Casuh] Address [220 Yuseong-gu, Gung-dong, Daejeon, Korea] Voice: [+82-31-709-5577, +82-42-821-6862], FAX: [+82-31-709-5578, +82-42-823-5586] E-Mail:[hsulee@etri.re.kr, dykim@cnu.kr, retaw@casuh.com] Re: [Contribution to IEEE 802.15.6 Meeting, July 2008] Abstract: [Propose multi preamble to enhance transmission performance] Purpose: [Proposal] 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.

Multi preamble to support Single MAC for multi PHY <July 2008> Multi preamble to support Single MAC for multi PHY July 2008 H. S. Lee ETRI D. Y. Kim and C. S. Eun Chungnam Univ. S. M. Ryu CASUH

Multiple Preamble Concept Fixed Multiple Variable Sync Aide Lock time Preamble Header Message EOF Conventional Frame Structure Sync Aide & Command Lock time Preamble Header Message EOF Suggested Frame Structure Multiple Preamble contains short message

Why Preamble is so important ? ☞ to synchronize frame Why frame synchronization is so important ? ☞ to demodulate message ☞ to enhance QoS of PHY with MAC Preamble detection error rate should be smaller than WBAN application requirement ☞ to reduce interference among different PHY We should not receive during adjacent radio is transmitting to avoid spurious interference

How to enhance QoS by MAC Quoted from doc.: IEEE 802. 15-08-0446-00-0006 written by Dr. Youjin Kim et al ETRI

How to avoid mutual interference Unified Frame R T T R R T R T R T I0 R T R T I1 I2 I3 O1 O2

Why 64bit preamble length is not enough Why 64bit preamble length is not enough ? ☞ Environment SNR might be under the 0 dB Spread Spectrum System operates in such condition WBAN Medical Application needs Spread Spectrum ☞ 2.4GHz fading effect is so severe SNR of received signal is drastically degraded We should consider enough margin ☞ Mutual Interference among adjacent cell’s becomes 3-D effect ubiquitous service cell planning needs 3-D interference

Process Gain for Medical Use ~7dB Non-Medical Medical Spread Spectrum Block ~14dB Medical ~Kbps Non-Medical 100Kbps Environment SNR might be under the 0 dB

2.4GHz Fading Effect SNR of received signal is drastically degraded

Self Organizing MAC is inevitable Ubiquitous Cell Planning 2-D 3-D GC1 GC2 GC4 GC8 GC26 GC1 GC2 GC3 GC8 ubiquitous Self Organizing MAC is inevitable Multi Preamble

False Alarm & False Dismissal Probability for Binary CDMA

False Alarm & False Dismissal Probability for Binary CDMA

False Alarm & False Dismissal Probability for WBAN 64bit is not enough but 128 bit is too high ; so we suggest multi Preamble

127 bit Gold Code Cross Correlation value

Simulation Result of Multi code Error Rate

Multi Preamble Pros & Cons Enhance Preamble Detection Rate Shorten transmission time Reduce Power Consumption Assign special preamble Emergency PHY Classification Cell Planning transmission speed CONS Complex Hardware ? Time Loss ?

Comparison Analysis and Simulation Results

Conclusion Multi Preamble Concept is suitable for WBAN Reduce transmission time & Power consumption Enhance QoS by perfect frame synchronization Special Preamble is possible ; emergency, cell planning, etc Demerits of multi preamble is negligible 128bit correlator H/W is not burden now Longer Preamble length is not time loss Multi Preamble could support new service in WBAN application Supply tool to make single MAC to support scalability Support special purpose service like emergence broadcasting Increase mobile channel capacity by Pico-cell Hand-over Planning Diversity, Selective Hopping, Service converging, etc