IEEE g Submission: Low power features for SUN 2 May 2009 Hirohito Nishiyama, Ryoji Ono, Seiichi HiraokaSlide 1 Project: IEEE P Working Group for Wireless Personal Area Networks (WPANs) Submission Title: [Low power features for SUN] Date Submitted: [2 May 2009] Source: [Hirohito Nishiyama] Company [Mitsubishi Electric Corp.] [Ryoji Ono] Company [Mitsubishi Electric Corp.] [Seiichi Hiraoka] Company [Mitsubishi Electric Corp.] Address [5-1-1 Ofuna, Kamakura, Kanagawa, Japan] Voice:[ ] Re: [IEEE g group] Abstract:Final proposal of low power features for IEEE g Purpose:To deploy low power features to enable multi-year battery operation. 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

IEEE g Submission: Low power features for SUN 2 May 2009 Hirohito Nishiyama, Ryoji Ono, Seiichi HiraokaSlide 2 Low power features for SUN Hirohito Nishiyama, Ryoji Ono, Seiichi Hiraoka Mitsubishi Electric Corp. 2 May. 2009

IEEE g Submission: Low power features for SUN 2 May 2009 Hirohito Nishiyama, Ryoji Ono, Seiichi HiraokaSlide 3 Contents Motivation Target Systems (Battery Operated Systems) Application Requirements Review of Power Saving Techniques Proposed features for SUN - Link control feature - Synchronized sample listening Requirements for PHY and MAC

IEEE g Submission: Low power features for SUN 2 May 2009 Hirohito Nishiyama, Ryoji Ono, Seiichi HiraokaSlide 4 Motivation There are some battery operated systems in the field of meter reading and outdoor control & monitoring. Such systems require multi-year battery life. IEEE could not satisfy requirements for these applications. IEEE g standard will need to provide low power features that enable multi-year battery operation.

IEEE g Submission: Low power features for SUN 2 May 2009 Hirohito Nishiyama, Ryoji Ono, Seiichi HiraokaSlide 5 Target Systems - Battery Operated Systems Meter reading for gas and water - In Japan, meters for gas and water should operate by battery. - Battery life should be over 10 years. - Deal with meter reading data and alarm of a gas leak and a fire. Out door control & monitoring - Environment and disaster monitoring e.g. climate, forest fire, landslide, ect - Urban monitoring and control e.g. streetlight control, security system, maintenance of equipment - These application require multi-year battery or solar battery operation. - Deal with event notification (sign of disaster, malfunction of equipment, etc) and some control of equipment.

IEEE g Submission: Low power features for SUN 2 May 2009 Hirohito Nishiyama, Ryoji Ono, Seiichi HiraokaSlide 6 Application Requirements Gas/Water Meter ReadingOutdoor Control & Monitoring battery life10 years1 to 5 years types of communications ・ meter reading data ・ alarm - gas leak, fire - malfunction of equipments ・ keep-alive ・ event notification - sign of disaster - change of condition - malfunction of equipment ・ keep-alive frequency of communication ・ several times a day for reading data and keep-alive ・ few or no for alarm ・ several times a day for keep- alive ・ few or no for event notification delay of communication ・ several seconds for alarm ・ several seconds for event notification

IEEE g Submission: Low power features for SUN 2 May 2009 Hirohito Nishiyama, Ryoji Ono, Seiichi HiraokaSlide 7 ■ Basic Sample Listening (B-MAC, etc) Procedure - Sender transmits a long preamble before sending data. - Receiver samples channel periodically and receives data when it detects preamble. Advantages of sample listening - Power consumption is very small, when not communicate. - Good response for asynchronous communication such as alarm or event notification. This technique are suitable for these applications Review of Power Saving Technique

IEEE g Submission: Low power features for SUN 2 May 2009 Hirohito Nishiyama, Ryoji Ono, Seiichi HiraokaSlide 8 Proposed features for SUN (1) Link control feature (2) Synchronized sample lestening

IEEE g Submission: Low power features for SUN 2 May 2009 Hirohito Nishiyama, Ryoji Ono, Seiichi HiraokaSlide 9 Proposed features - link control ■ Issue of basic sample listening ・ On Monitoring System - The communication of event notification tends to concentrate at the same time. (e.g. a fire, malfunction caused by disaster) - The monitoring system requires more data to investigate in detail, when it detects event notification. (e.g. a malfunction of equipment) ・ But... - Long preamble consumes large capacity of communication. - Long preamble increases the delay of communication. detection a fire detection a fire detection a fire

IEEE g Submission: Low power features for SUN 2 May 2009 Hirohito Nishiyama, Ryoji Ono, Seiichi HiraokaSlide 10 ■ Control nodes' mode with "LinkUp" and "LinkDown" command. 1) The source node sends the LinkUp/LinkDown command to destination to inform of start/end of communication. 2) If the receiver receives the LinkUp/LinkDown, it changes the mode to Communication/Sampling. Proposed features - link control (cont.)

IEEE g Submission: Low power features for SUN 2 May 2009 Hirohito Nishiyama, Ryoji Ono, Seiichi HiraokaSlide 11 Proposed features - link control (cont.) ■ Use Link information to reduce long preamble frame - Each node keeps the information of the link concerned. - Link information consist of source node, destination node, next-hop node. - If the next hop node is obviously in the communication mode, the sender sends LinkUp command with short preamble. This Function should be implement in network layer Node A Node B Node C Node D Node E Link has already been established Node D to A LinkUp with short preamble LinkUp with long preamble

IEEE g Submission: Low power features for SUN 2 May 2009 Hirohito Nishiyama, Ryoji Ono, Seiichi HiraokaSlide 12 Proposed features - synchonized sample listening ■ Issue of basic sample listening - On FHSS system, FHSS also should be deployed to sample listening feature to ensure the robustness of communication. - Long preamble make the neighbor nodes that are not concerned with communication wasted power.

IEEE g Submission: Low power features for SUN 2 May 2009 Hirohito Nishiyama, Ryoji Ono, Seiichi HiraokaSlide 13 Proposed features - synchonized sample listening (cont.) ■ Synchronized to FHSS, using another channel to FHSS - The node that works in sampling mode hops same timing with FHSS's frequency hopping. - If the hopping pattern for sample listening is different from for data communication, sample listening would not interfere with data communication. ( e.g. Figure shows the node uses next channel to data communication )

IEEE g Submission: Low power features for SUN 2 May 2009 Hirohito Nishiyama, Ryoji Ono, Seiichi HiraokaSlide 14 Proposed features - synchronized sample listening (cont.) ■ Synchronized sample listening - One or more timeslots create in the requency hopping interval - The length of timeslot is about 20ms to frequency hopping interval. The longer timeslot extend the synchronization interval. - Each node is assigned some timeslots for sampling. - Timeslot assignment depends on system design. (1)one time slot for multiple nodes, (2)multiple time slots for one node.

IEEE g Submission: Low power features for SUN 2 May 2009 Hirohito Nishiyama, Ryoji Ono, Seiichi HiraokaSlide PHY data service Tow types of frame should be supported. 1) The existing frame in current standard. 2) The frame with long preamble. The length of preamble should be defined in PIB PHY management service PLME-SET-TRX-STATE.request Four types of transceiver state (mode) should be supported 1) Transceiver disable (TRX_OFF) 2) Transmitter enabled (TX_ON) 3) Receiver enabled (RX_ON) 4) Sampling enabled (SMP_ON) In this mode, sampling should be performed, and only the frame with long preamble should be received. Requirements for PHY Existing Mode

IEEE g Submission: Low power features for SUN 2 May 2009 Hirohito Nishiyama, Ryoji Ono, Seiichi HiraokaSlide 16 Requirements for PHY 6.8 General radio specifications 6.8.? Channel sampling function definitions 1) Timing for sampling 2) Function of checking preamble pattern It will help to make the transceiver's power off quickly, if it gets noise or signal of data communication.

IEEE g Submission: Low power features for SUN 2 May 2009 Hirohito Nishiyama, Ryoji Ono, Seiichi HiraokaSlide 17 Requirements for MAC sublayer These are specifications for slow-FHSS system. 7.5 MAC functional discription 7.5.? Synchronization - Synchronization for synchronized sample listening use the FHSS mechanism. - Synchronization interval should be defined with consideration of length of timeslot and accuracy of crystal. 7.5.? Channel management - Channel management for synchronized sample listening should be defined in order to avoid interference with the data communication.

IEEE g Submission: Low power features for SUN 2 May 2009 Hirohito Nishiyama, Ryoji Ono, Seiichi HiraokaSlide 18 Conclusion Reviewed target systems and their requirements. Referred to basic sample listening method Proposed two low power features for SUN (1) link control feature (2) Synchronized sample listening Explained requirements to PHY and MAC

IEEE g Submission: Low power features for SUN 2 May 2009 Hirohito Nishiyama, Ryoji Ono, Seiichi HiraokaSlide 19 Any Questions?

IEEE g Submission: Low power features for SUN 2 May 2009 Hirohito Nishiyama, Ryoji Ono, Seiichi HiraokaSlide 20 Thanks!