WIRELESS SENSOR NETWORK WAKE-UP RANGE EXTENSION VIA ENERGY HARVESTING AND EDGE DEVICES

• US 20140254445A1
• Filed: 03/06/2014
• Published: 09/11/2014
• Est. Priority Date: 03/08/2013
• Status: Active Grant

• Current Assignee: University of Rochester
• Original Assignee: University of Rochester
• Inventors: Heinzelman, Wendi, Ba, He, Chen, Li
• Granted Patent: US 9,232,475 B2
• Time in Patent Office: Days
• US Class Current: 370/311
• CPC Class Codes: H04W 52/0229 where the received signal is a wanted signal
• CPC Class Codes: H04W 52/0235 where the received signal is a power saving command
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

An enhanced, ultra low power passive wake-up radio-based sensor includes a passive wake-up radio-based sensor node having an energy harvester and low power wake-up circuit to improve the wake-up range for passive wake-up radio sensor nodes without the need for local power. The wake-up sensor may additionally include a transmitter for providing a wake-up signal to nodes that are outside the wake-up range of a base.

Claims

1. A wake-up radio sensor node, comprising:

an energy harvesting circuit for collecting energy from a wireless signal and outputting a voltage based on said collected energy;

a wake-up circuit comprising a wake-up pulse generator interconnected to said energy harvesting circuit for receiving said output voltage of said energy harvesting signal and using said output voltage to generate a wake-up signal;

a wireless sensor having a sleep mode and an active mode interconnected to said wake-up circuit to receive said wake-up signal, wherein said sensor is programmed to enter said active mode from said sleep mode in response to receiving said wake-up signal; and

a power source interconnected to said wireless sensor.

2. The node of claim 1, wherein said wake-up pulse generator generates said wake-up signal after said voltage exceeds a predetermined threshold.

4. The node of claim 1, wherein said wireless sensor is programmed to send any data when said wireless sensor enters said active mode from said sleep mode.

5. The node of claim 4, wherein said wireless sensor is programmed to enter said sleep mode after sending data when in said active mode.

6. The node of claim 1, wherein said power source only supplies power to said wireless sensor for sensing and data communication.

3. The node of claim 3, wherein predetermined threshold is 1.5 volts.

7. A multi-hop wireless wake-up radio sensor node, comprising:

an energy harvesting circuit for collecting energy from a wireless signal and outputting a voltage based on said collected energy;

a wake-up circuit comprising a wake-up pulse generator interconnected to said energy harvesting circuit for receiving said output voltage of said energy harvesting signal and using said output voltage to generate a wake-up signal;

a wireless sensor interconnected to said wake-up circuit to receive said wake-up signal and configured to output a node wake-up signal when said wake-up signal is received;

a wireless transmitter interconnected to said wireless sensor module for transmitting said node wake-up signal; and

a power source interconnected to said wireless sensor module and said wireless transmitter.

8. The node of claim 7, wherein said wireless transmitter comprises a radio-frequency identification reader and a dual-channel power distribution switch.

9. The node of claim 7, wherein said wireless sensor includes a timer for counting a predetermined period of time that commences after said node wake-up signal is transmitted.

10. The node of claim 9, wherein said wireless sensor is programmed to receive data from a nearby node before said predetermined period of time elapses.

11. The node of claim 10, wherein said wireless sensor is set to a multi-hop mode if data is received from a nearby node prior to said predetermined period of time elapsing.

12. A method of extending the wake-up range of a radio sensor node, comprising the steps of:

using an energy harvesting circuit to collect energy from a wireless signal;

outputting a voltage based on said collected energy;

using said output voltage to generate a wake-up signal;

providing said signal to a wireless sensor having a sleep mode and an active mode; and

wherein said sensor enters said active mode from said sleep mode in response to receiving said wake-up signal.

13. The method of claim 12, further comprising the step of supplying power to just said wireless sensor from a power source.

14. The method of claim 12, wherein said wake-up signal is generated after said voltage exceeds a predetermined threshold.

15. The method of claim 14, wherein predetermined threshold is 1.5 volts.

16. The method of claim 15, wherein said wireless sensor transmits data after said wireless sensor enters said active mode from said sleep mode.

17. The method of claim 15, wherein said wireless sensor enters said sleep mode after sending data in said active mode.