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: [Smart Grid Communications Preliminary Proposal] Date Submitted: [March 1, 2009] Source: [Scott Weikel] Company [Elster Electricity] [Robert Mason] Company [Elster Electricity] [Jeff McCullough] Company [Elster Electricity] [David Hart] Company [Elster Electricity] Address: [208 South Rogers Lane; Raleigh, NC 27610] Voice:[919-250-5819] E-Mail: [david.g.hart@us.elster.com] Re: [TG4-SUN PHY Layer Proposal] Abstract: Preliminary Proposal for Smart Utility Networks aka Smart Grid Communications Purpose: Contribution to Smart Grid Communications 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. Doc: IEEE 15-09-127-02-004g

2. Proposal to TG4-SUN Smart Grid Communications March 12, 2009 IEEE 802.15.4g

3. The Smart Grid vision… Secure standards based communications help to improve electric system operation Enables alternate forms of energy generation and usage Proactively alerts utility of problems on the grid Empowers consumers with information Supports Green initiatives

4. Smart Grid Needs • Provide usage information to consumers • Provide information from power grid • Bi-directional and net metering for new power sources • Electric consumption data on hourly or sub-hourly basis • Water consumption • Gas consumption • Support business logistics • On-request reads • Operational control • Outage and restoration management • Support for future applications

5. Network Considerations • Endpoints at all points of service or in premise • Not mobile – limited installation options • Requires robust communications over long distances • Battery powered water and gas devices • Up to 20 years life • Support broadcast messages for utility applications such as load control • Support on request reads in seconds • Support control in seconds • Secure to prevent others from un-authorized access or denial of service

6. SUN – Smart Grid Examples

7. Real World Deployment • Technology based on 900 MHz FHSS has been field proven • Over 2 million smart grid points are deployed • In Home Display • Programmable Control Thermostat • Electric meters • Water registers • Gas registers • 50+ Systems deployed 7 different countries • 5 Years experience with true 2-way utility smart grid communications

8. Scope/Goals of TG4g-SUN • Define an alternate PHY layer for 802.15.4 with only those MAC modifications needed to support the PHY layer implementation • Support operation in any of the regionally available license exempt frequency bands, such as 700MHz to 1GHz, and the 2.4 GHz band • Data rate of at least 40 kbps but not more than 1000 kbps • Achieve the optimal energy efficient link margin given the environmental conditions encountered in Smart Metering deployments • Principally outdoor communications • PHY frame sizes up to a minimum of 1500 octets • Simultaneous operation for at least 3 co-located orthogonal networks • Connectivity to at least one thousand direct neighbors characteristic of dense urban deployments • Provide mechanisms that enable coexistence with other systems in the same band(s) including IEEE 802.11, 802.15 and 802.16 systems

9. Proposal to Address Goals of TG4-SUN Define an alternate PHY layer for 802.15.4 with only those MAC modifications needed to support the PHY layer implementation Overview of Proposed PHY Layer • 902-928 MHz ISM band where available • FSK modulation • 400 kHz channel spacing to support higher data rates • Two bands in 902-928 MHz region. Each band uses 25 channel FHSS • Programmable output power (to suit various device types) • Data rates between 9.6 and 300 kbps

10. Proposal to Address Goals of TG4-SUN Support operation in any of the regionally available license exempt frequency bands, such as 700MHz to 1GHz, and the 2.4 GHz band Comparison of frequency bands • 2.4 GHz band is very congested and doesn’t offer the robust PHY layer required to meet the requirements of Smart Utility Networks (SUN) • 902-928 MHz band offers both bandwidth and robustness required to meet the requirements • Proposal is not restricted to the 902 – 928 MHz band, but satisfies the goals within one band

11. Proposal to Address Goals of TG4-SUN Support operation in any of the regionally available license exempt frequency bands, such as 700MHz to 1GHz, and the 2.4 GHz band Comparison of 900 MHz and 2.4 GHz unlicensed bands (if 900 MHz available) • 900 MHz signals propagate farther than 2.4 GHz • Free space loss is approx. 10 dB higher for 2.4 GHz as compared to 900 MHz • Distance of 900 MHz is typically 2.5 times better than 2.4 GHz • 900 MHz signals penetrate better than 2.4 GHz • Ability to overcome obstacles (buildings, trees) • Buildings, and other obstacles attenuate 2.4 GHz more than 900 MHz • 900 MHz signals are absorbed less than 2.4 GHz • Multi-path fading (reflection) is worse at higher frequencies • Walls, pine needles, other materials absorb (attenuate) 2.4 GHz more than 900 MHz • Weather (fog, rain) attenuate 2.4 GHz more than 900 MHz

12. Proposal to Address Goals of TG4-SUN Data rate of at least 40 kbps but not more than 1000 kbps Proposed PHY Layer • Supports variable data rates between 9.6 and 300 kbps • Data rate allowed to vary based on device type • Provides a low data rate for simple low end devices, while also providing a higher data rates for large data/message transport

13. Proposal to Address Goals of TG4-SUN Achieve the optimal energy efficient link margin given the environmental conditions encountered in Smart Metering deployments • Proven operation in Smart Metering deployments • Proven in outdoor environments • Proven with electric, gas, and water smart meters • Proven reliable communications to bridge utility to in-home devices • Supports communications from meter into the home • Both single family residential and multi-unit structures (e.g. apartment complexes)

14. Proposal to Address Goals of TG4-SUN Principally outdoor communications • Communication backbone is principally outdoors, BUT it is critical to get from the meter into the home • Must get from electric meter into the home to water meter • Must support multi-home dwellings • Propagation distances and penetration of 900 MHz signals provides range and robustness for outdoor communications AND provide optional communications INTO the residence for functions such as load control

15. Proposal to Address Goals of TG4-SUN PHY frame sizes up to a minimum of 1500 octets • Long packets will increase probability of errors • Simple PHY frame structure • Variable frame size • Support smaller block sizes with extensions to 1500 or more octets • Particularly for low power applications • Support for large payloads • Data whitening performed as software algorithm – no PHY space required for whitening

16. Proposal to Address Goals of TG4-SUN Simultaneous operation for at least 3 co-located orthogonal networks • Support multiple channels to enable up to three orthogonal networks if required • Not all mesh implementations require 3 simultaneous orthogonal networks • Some simultaneous orthogonal networks may require ‘chatter’ to synchronize • Three networks in the 902-928 frequency band may enforce a bandwidth limitation that is not desired • With frequency hopping systems, FCC requirements specify minimum bandwidth requirements • Proposed option supports two networks in the 902-928 MHz band • Both networks can fully co-exist at ¼ W • Devices can participate in only one or both networks

17. Proposal to Address Goals of TG4-SUN Simultaneous operation for 2 co-located orthogonal networks • 2 networks in a given frequency band. • Example, 902-928 MHz band: • 400 kHz channel spacing. 25 channels for each network • Split frequency allocation provides flexibility for international locations where 902-915 MHz region is not available for use, but 915-928 MHz region is available. • Allows a single device to operate on two networks with minimal hardware

18. Proposal to Address Goals of TG4-SUN Connectivity to at least one thousand direct neighbors characteristic of dense urban deployments • Networks deployed and demonstrating more than one thousand direct neighbors • Network structure is primarily based on a network coordinator to multiple devices and supports peer to peer communications • Millions of devices deployed around the world

19. Proposal to Address Goals of TG4-SUN Provide mechanisms that enable coexistence with other systems in the same band(s) including IEEE 801.11, 802.15, and 802.16 • FHSS communications provides best option for coexistence • Fixed channel selection (as per DSSS) is not required • 900 MHz band is less crowded and avoids many other systems (801.11, 802.15, 802.16) that are predominately in other bands • Proven network performance in the presence of commonly encountered interference sources

20. Proposal to Address Goals of TG4-SUN Key Points • Need to support utility requirements for electric, water, and gas meters • Otherwise standard encompasses less than today’s systems • Need to support low data and high data for advanced grid features • Water/Gas reads, Electric reads, Network control • Networks: 1, 2, or 3 possible • 900 MHz FHSS FSK proven in the field • Proven performance in both dense and sparse deployments

21. Thank you!!