Katsuyuki KARIYA † , Tatsuya NAKAMURA † , Shinji TAKEUCHI † , Atsushi OTOGAWA †

1. Investigation of Wireless Telecommunication for AMI Katsuyuki KARIYA†, Tatsuya NAKAMURA†, Shinji TAKEUCHI†, Atsushi OTOGAWA† Yukio IWASHIMA††, Yasuhisa MATSUSHITA†† Hitoshi KUBOTA†††, Toshihiro INOUE††† † : Chubu Electric Power Co., Inc., †† : ChubuSeiki Co., Ltd., ††† : Mitshubishi Electric Corporation Katsuyuki KARIYA – Japan – Distribution network business activities and impact of regulation – 0737

2. Outline • Introduction • Measured wireless media • Conditions of measurements • Results of the Investigation • Summary Katsuyuki KARIYA – Japan – Distribution network business activities and impact of regulation – 0737

3. Introduction • Why Advanced Metering Infrastructure (AMI)? • Improves efficiency of meter reading • Energy conservation • Future; Efficient operation of power distribution under condition in which distributed power source are widely spread, etc Katsuyuki KARIYA – Japan – Distribution network business activities and impact of regulation – 0737

4. Server Computers WAN GW SMN SM Introduction • What’s Advanced Metering Infrastructure (AMI)? • Millions of smart meters (SMs) perform two-way communication with Server computer via smart meter networks(SMNs), Gateways (GWs), and Wide area network (WAN). A Model of AMI System Katsuyuki KARIYA – Japan – Distribution network business activities and impact of regulation – 0737

5. Introduction • Why wireless telecommunication? • Number of meters per service transformer is small (About 10~20 meters) • Meters are installed outside The installation cost of the PLC coupler is expensivein Japan. Therefore, the wireless is more cost effective . Katsuyuki KARIYA – Japan – Distribution network business activities and impact of regulation – 0737

6. Introduction • What's suitable wireless media for AMI system? • Easy to use • Low cost • License Free Wireless media in Japan • 2.4GHz wireless LAN • 950MHz Low Power Radio • 429MHz Low Power Radio • Radio propagation characteristics of three kinds of license free wireless communication media were investigated. Katsuyuki KARIYA – Japan – Distribution network business activities and impact of regulation – 0737

7. Measured wireless media *1 : Direct Sequence Spread Spectrum *2 : Gaussian Frequency Shift Keying *3 : Association of Radio Industry Business Katsuyuki KARIYA – Japan – Distribution network business activities and impact of regulation – 0737

8. Conditions of Measurements • Measurements excecuted under condition which simmulated communication • Between a GW placed on a utility pole and SMs of detached houses. • Between a GW placed on a utility pole and SMs in pipe shafts of an apartment building. • Among SMs in pipe shafts of an apartment. Katsuyuki KARIYA – Japan – Distribution network business activities and impact of regulation – 0737

9. Conditions of Measurements Communication between GW and SM of detached house • A transmitter was placed on a handrail of outside stairs of an apartment building. • Receivers were placed by utility poles around the apartment building. 1.8m 6m Transmitter Receiver Katsuyuki KARIYA – Japan – Distribution network business activities and impact of regulation – 0737

10. Conditions of Measurements Communication between GW and SM in Apartment Building • A transmitter was placed in a pipe shaft of an apartment building. • Receivers were placed by utility poles around the apartment building. 1.8m Pipe Shaft Transmitter Receiver Katsuyuki KARIYA – Japan – Distribution network business activities and impact of regulation – 0737

11. Conditions of Measurements Communication among SMs in an Apartment Building • Both transmitter and receivers were placed in pipe shafts of an apartment building. Transmitter & Receiver Katsuyuki KARIYA – Japan – Distribution network business activities and impact of regulation – 0737

12. Results of measurements • Received Signal Power vs. Packet Error rate Serviceable area Wherereceived signal power is strong enough and packet error hardly occurs. Fringe area Where packet error increases Unserviceable area Received signal power is so weak that packet error frequently occurs. 2.4GHz wireless LAN Received Signal Power vs. Packet Error Rate Katsuyuki KARIYA – Japan – Distribution network business activities and impact of regulation – 0737

13. Results of measurements • Classification of measurements Results Katsuyuki KARIYA – Japan – Distribution network business activities and impact of regulation – 0737

14. 0° 0° 0° 90° 90° 90° 100m 270° 100m 100m 270° 270° 200m 180° 180° 200m 180° 200m Serviceable Area Fringe Area Unserviceable Area Reinforced Concrete Building Clear Space Results of measurements Communication between GW and SM of detached house(1) (a)2.4GHz Wireless LAN (b)950MHz Low Power Radio (c)429MHz Low Power Radio Katsuyuki KARIYA – Japan – Distribution network business activities and impact of regulation – 0737

15. Results of measurements Communication between GW and SM of detached house(2) • 950MHz low power radio had longest range in the three wireless media. • All of the three wireless media had difficulty to establish communication across the apartment building nearby. Katsuyuki KARIYA – Japan – Distribution network business activities and impact of regulation – 0737

16. 0° 0° 0° 90° 90° 90° 270° 270° 270° 30m 30m 30m 180° 180° 180° Serviceable Area Fringe Area Unserviceable Area Reinforced Concrete Building Clear Space Results of measurements Communication between GW and SM in Apartment Building(1) (c)429MHz Low Power Radio (a)2.4GHz Wireless LAN (b)950MHz Low Power Radio Katsuyuki KARIYA – Japan – Distribution network business activities and impact of regulation – 0737

17. Results of measurements Communication between GW and SM in Apartment Building(2) • 429MHz low power radio could establish communication between inside of a pipe shaft and utility poles on both steel door’s side and its opposite side of the pipe shaft. • 2.4GHz wireless LAN and 950MHz low power radio had difficulty in communication between SM and GW on a steel door’s side of the pipe shaft. Katsuyuki KARIYA – Japan – Distribution network business activities and impact of regulation – 0737

18. Results of measurements Communication among SMs in Apartment Building(1) Chose an apartment building which has long distance between each pipe shafts. Katsuyuki KARIYA – Japan – Distribution network business activities and impact of regulation – 0737

19. Fringe Area Unserviceable Area Serviceable Area Transmitter Tx Results of measurements Communication among SMs in Apartment Building(2) Poor communication with adjacent pipe shafts Good communication even with adjacent pipe shaft (c)429MHz Low Power radio (a)2.4GHz Wireless LAN (b)950MHz Low Power radio Katsuyuki KARIYA – Japan – Distribution network business activities and impact of regulation – 0737

20. Results of measurements Communication among SMs in Apartment Building(3) • 429MHz low power radio could establish communication not only between SMs in same pipe shaft or between SMs in adjacent pipe shafts on same floor but also between SMs in adjacent pipe shafts on different floors. Katsuyuki KARIYA – Japan – Distribution network business activities and impact of regulation – 0737

21. Summary • In view of serviceable area 950MHz low power radio is the most suitable communication media for smart meter network. • 429MHz low power radio has advantages over two other wireless media for communication in apartment buildings. Katsuyuki KARIYA – Japan – Distribution network business activities and impact of regulation – 0737

22. Summary • The results of this investigation shows differences of radio propagation characteristics among wireless media. • Steady SMN must be built with selecting suitable wireless media for conditions of meter installation. Katsuyuki KARIYA – Japan – Distribution network business activities and impact of regulation – 0737

23. Thank you for your attention. We Japanese are grateful for the kindness of people of all over the world. Katsuyuki KARIYA – Japan – Distribution network business activities and impact of regulation – 0737