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: [ Supporting 4E/4G Joint MAC Functions for Smart Grid ] Date Submitted: [8 July, 2009] Source: [] Company [SIMIT, Vinno, Huawei] Address [No.865 Changning Road, Shanghai, 200050, China] Voice:[+86 21 6251 1070], FAX:[+86 21 6213 2314], E-Mail:[ huangheqing@mail.sim.ac.cn, sqinghe@mail.sim.ac.cn] Re: [IEEE 802.15.4g group] Abstract: A proposal of MAC layer for Smart Grid to meet the requirement and characteristic. Purpose: Presented to the 802.15.4g SUN Task Group for consideration 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.

2. Multiple Application for Chinese SUN • Smart Grid and Smart home • Energy monitoring and measurement • Direct load control • Remote Diagnosis and control • WAMACS (Wide Area Measurement and Control System) • Synchrophasor measurement • Reliable wide area communication network • Grid Device online monitoring • Transformer monitoring • Disjunctor monitoring • line capacity monitoring

3. Basic Requirement for MAC • Compatible interface design with 802.15.4 MAC • Coexistence with other systems in the same band（s） • Common interface to support: • Different frequency • 470～510MHz (Chinese Measurement Instrument) • 780MHz (CWPAN and 15.4c) • 868, 915, 2400MHz (15.4) • Different Modulation • DSSS on Broad Bands • FSK or GFSK on Narrow Bands • Low Delay • High reliability • Ensure synchronizing precision • Low energy consumption, long lifetime

4. Some key Functions • Hierarchical network structure • The network deployment is inequality and heterogeneous • Coordinators/routers are more powerful to ensure reliability • Multi-channel supporting • Asynchronous method • Synchronous method

5. Hierarchical network structure • Backbone • Coordinator/router act as backbone • No common channel, multi-channel mesh • Local grid • Local grid nodes act as cluster/Tree • single channel, modified 15.4MAC

6. Multi-channel supporting MAC:Asynchronous method（1） • No common channel, multi-channel mesh • Receiver-based channel Adaptation • Non-beacon, wake-up/sleep duty cycle

7. Asynchronous method（2） • Sender-driven communication • Each device is listening to its own channel. • The sender device switch to the receiver’s channel, transmit Wakeup command and switch back to its own channel, waiting for receiver’s confirm. • The receiver reveived the Wakeup command, switch to sender’ s channel, and transmit confirm, then switch back to its own channel, waiting for DATA frame. • The sender device switch to receiver’s channel, transmit DATA frame. • The receiver device switch to the sender’s channel and transmit a ACK frame (if requested).

8. Synchronous method – modified 15.4e EGTS Channels CH0 CH1 CH2 … • Common channel : Beacon and CAP use a fixed single channel. • Multi-channel for Enhanced GTS • EGTS slot = tuple (time slot, channel) • More than one slot can be allocated for each link (Tx & Rx pair). • Multi-hop extension for EGTS • The usage of EGTS is extended to the nodes beyond one hop distance from PAN coordinator. • Beacon scheduling is required to provide multi-hop connection. • Multi-superframe extension for EGTS • A multi-superframe consists of N superframes. • The allocation pattern is repeated every multi-superframe. • We define MO (multi-superframe order) such that N = 2(MO – SO), where MO ≥ SO. • Multi-superframe Duration MD = aBaseSuperframeDuration*2MO symbols EGTS Slots

9. Multiple topologies support Tree and mesh and star Channel diversity Controlled channel hopping Adaptive slot and channel allocation Optional distributed channel hopping Time synchronization Low power Sampled listening CAP reduction Enhanced ACK Secure and robust ACK Group ACK Reduced MAC header Resource scheduling Multiple QoS support Distributed slot and channel allocation Distributed beacon scheduling Backward compatibility to 802.15.4 -2006 Behaviors Supported by 4e MAC

10. MAC for both 4e and 4g • Now 4e MAC is a full functional MAC with all above features and capable of supporting 4g PHY and Applications. • 4e MAC has already supported various industrial applications, so setting a new MAC for 4g is not the best choice for many companies. • 4e/g liaison can be an efficient way to resolve all the problems about MAC.

11. Thank you July. 2009 HQ Huang, J.Shen Slide 11