1. Author : Yu-Ping Chen, Quincy Wu
Power Consumption Measurement and Clock Synchronization on Low-Power Wireless Sensor Networks
Author : Yu-Ping Chen, Quincy Wu

2. Introduction
Applications of Wireless Sensor Networks

3. Introduction cont.
Low-Power WiFi system architecture

4. Introduction cont.
Digital oscilloscope connection diagram.

5. Power Consumption Measurement
Low-Power WiFi and ZigBee
--The electric current of beaconing status when the Low-Power WiFi signaling strength is -32 dBm.
--The stand-by status of ZigBee.

6. Power Consumption Measurement cont.
--The start- up status
of Low-Power WiFi.
--The start- up status
of ZigBee.

7. Power Consumption Measurement cont.
Average power consumption statistics.
Power State
ZigBee
Low-Power WiFi
Signaling strength
-32 dBm
-79 dBm
Start-up W W
Beaconing W W
Stand-by W W

8. Clock Synchronization
Clock synchronization of Low-Power WiFi devices by NTP.

9. Clock Synchronization cont.
Clock synchronization flow chart with NTP.

10. Conclusion and Future work
Compared with traditional WiFi equipment, the power consumption of Low-Power WiFi is reduced approximate 40%.
The power consumption of Low-Power WiFi with start-up and stand-by status is lower than ZigBee.
The power consumption of Low-Power WiFi device when it is receiving beacons from an AP, is twice of the power consumption at its stand-by status.

11. Conclusion and Future Work cont.
The clock synchronization usually suffers from long latency problems in wireless sensor networks like ZigBee.
We combines Low-power WiFi devices with NTP, it would be crucial to further investigate the efficiency and accuracy of NTP packet transmission.

12. Thanks for your attention.