SYSTEM AND METHOD FOR WIRELESS SENSOR NETWORKS

• US 20120327831A1
• Filed: 03/03/2011
• Published: 12/27/2012
• Est. Priority Date: 03/04/2010
• Status: Active Grant

• Current Assignee: Quantislabs Limited
• Original Assignee: Quantislabs Limited
• Inventors: Arendás, Csaba
• Granted Patent: US 9,167,516 B2
• Time in Patent Office: Days
• US Class Current: 370/311
• CPC Class Codes: H04W 52/0216 using a pre-established activity schedule, e.g. traffic indication frame
• CPC Class Codes: H04W 84/18 Self-organising networks, e.g. ad-hoc networks or sensor networks
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

Wireless sensor networks includes nodes configured to operate according to an 802.11-compliant communication protocol in an ad hoc mode in a multi hop network. The nodes include a power management unit configured to control operating states of a sensor control unit, a computing and storage unit and a communication unit of the node so that sensor measurements and inter-node communications occur at designated, coordinated times.

Claims

1. A method for measuring and communicating data using an 802.11-compliant communication protocol comprising:

powering on a power management unit via a power supply unit at a first communication node;

powering on a computing and storage unit, communications unit and sensor control unit of said first communication node;

measuring data via the sensor control unit at said first communication node;

powering off the sensor control unit of said first communication node after measuring data;

storing the data at said first communication node;

obtaining a time value from a real time clock module at said first communication node;

synchronizing the time value with other communication nodes;

synchronizing the data with other communication nodes;

storing data obtained from other communication nodes at said first communication node;

powering off the communications unit;

placing the power management unit in a lower power consumption state;

powering off the computing and storage unit.

2. The method of claim 1, wherein after measuring data via the sensor control unit sending data to the power management unit of said first communication node, and after powering off the sensor control, forwarding data to the computing and storage unit and storing data at the computing and storage unit.

3. The method of claim 1, wherein the sensor control unit measures data at two or more intervals within an hour and buffers data at the power management unit between intervals and powers off between intervals.

19. The communication node of claim 1, wherein total power consumption of the communication node does not exceed 10 mAh/hour, assuming at least 4 measurements and 1 communication per hour.

20. The communication node of claim 1, wherein power consumption of the communication node does not exceed 5 mAh/hour, assuming there are at least 4 measurements and 1 communication per hour.

21. The communication node of claim 1, wherein power consumption of the communication node does not exceed 3 mAh/hour, assuming there are at least 4 measurements and 1 communication per hour.

22. The communication node of claim 1, wherein power consumption of the communication node does not exceed 0.14 mAh/hour, assuming there are at least 4 measurements and 1 communication per hour.

23. The communication node of claim 1, wherein the total duty cycle of the 802.11-compliant communication protocol is 1% of the duty cycle of conventional. 802.11-compliant devices.

25. The communication node of claim 1, wherein the total duty cycle of the 802.11-compliant communication protocol is between the range of 0.3% -1% of the duty cycle of conventional 802.11 compliant devices.

26. The communication node of claim 1, wherein the total duty cycle of the 802.11-compliant communication protocol is between the range of 0.006%-0.3% of the duty cycle of conventional 802.11 compliant devices.

29. The method of claim 1, wherein an 802.16 compliant communications protocol is used in lieu of the 802.11 compliant communications protocol.

4. A communication node, comprising:

a power supply unit designed to supply electrical power for the node;

a sensor control unit configured to interface with one or more sensors;

a computing and storage unit configured to manage processing and storage of data gathered by the sensors;

a communication unit having a communication adapter configured to operate, under instruction from the computing and storage unit, according to an 802.11-compliant communication protocol in an ad hoc mode in a multi hop network, and

a power management unit coupled to receive power from the power supply unit and configured to control operating states of the sensor control unit, the computing and storage unit and the communication unit according to a wireless sensor network communication protocol in which sensor measurements and inter-node communications occur at designated times.

5. The communications node of claim 4, wherein the ad hoc mode can be switched to infrastructure mode.

6. The communication node of claim 4, wherein the power supply unit comprises one or more batteries.

7. The communication node of claim 4, wherein the power supply unit further comprises a solar panel coupled to a solar charging unit, the solar charging unit further coupled to the one or more batteries and configured to charge the batteries using electrical power produced by the solar panel.

31. The method of claim 4, wherein an 802.16 compliant communications protocol is used in lieu of the 802.11 compliant communications protocol.

8. A method of operating a communication node in a communication network, comprising:

providing electrical power from a power supply unit of the communication node to a power management unit of the communication node;

activating, by the power management unit, at a designated time, a sensor control unit of the communication node and acquiring data provided by a sensor controlled by the sensor management unit, said data being buffered by the power management unit;

placing the sensor control unit in an off state and powering up, at the direction of the power management unit, a computing and storage unit of the communication node,

transferring the data from the power management unit to the computing and storage unit and storing the data in a memory accessible by the computing and storage unit;

at a designated time for communication of the data, under the control of the power management unit, placing an 802.11-compliant communication protocol communication adapter of a communication unit of the communication node in an operational state and transmitting the data from the computing and storage unit to another node of the communication network and subsequently placing the communication unit in an off state;

otherwise,

placing the computing and storage unit in an off state.

9. The method of claim 8, wherein the off state is replaced by a low power consumption state.

10. The method of claim 8, wherein prior to the communication unit transmitting the data from the computing and storage unit to another node of the communication network, synchronizing a real time clock of the power management unit with a master clock of anode of the communication network.

11. The method of claim 10, wherein the synchronization is performed using a network time protocol.

12. The method of claim 10, wherein the master clock is selected according to a selection protocol.

13. The method of claim 8, wherein prior to placing the computing and storage unit in an off state, storing data received from another node in the communication network.

14. The method of claim 8, wherein prior to transmitting the data, constructing a routing table of other nodes in the communication network.

24. The method of claim 8, wherein the total duty cycle of the 802.11-compliant communication protocol is 1% of the duty cycle of conventional 802.11 compliant devices.

27. The method of claim 8, wherein the total duty cycle of the 802.11-compliant communication protocol is between the range of 0.3% -1% of the duty cycle of conventional 802.11 compliant devices.

28. The method of claim 8, wherein the total duty cycle of the 802.11-compliant communication protocol is between the range of 0.006% -0.3% of the duty cycle of conventional 802.11 compliant devices.

30. The method of claim 8, wherein an 802.16 compliant communications protocol is used in lieu of the 802.11 compliant communications protocol.

32. The method of claim. 8, wherein prior to transmitting the data, reusing routing tables form previous communications.

33. The method of claim 8, wherein prior to synchronizing a real time clock of the power management unit with a master clock of a node of the communication, network, transmitting the data from the computing and storage unit to another node of the communication network.

15. A wireless sensor network system, comprising communication nodes;

the communication nodes further comprising;

a power supply unit designed to supply electrical power for the node;

a sensor control unit configured to interface with one or more sensors;

a computing and storage unit configured to manage processing and storage of data gathered by the sensors;

a communication unit having a communication adapter configured to operate, under instruction from the computing and storage unit, according to an 802.11-compliant communication protocol in an ad hoc mode in a multi hop network; and

a power management unit coupled to receive power from the power supply unit and configured to control operating states of the sensor control unit, the computing and storage unit and the communication unit according to a wireless sensor network communication protocol, in which sensor measurements and inter-node communications occur at designated times;

wherein said sensor measurements, transformed into machine-readable data, are communicated to a computing device over said inter-node communications and displayed to a user of said wireless sensor network system on said computing device.

16. The system of claim 15, wherein said sensor is selected to measure a factor from the group consisting of:

temperature, humidity, infra-red light, solar radiation, wind speed wind direction, precipitation, soil moisture, leaf wetness, barometric pressure, soil pressure, pH, oxygen, carbon dioxide and ozone.

17. The system of claim 15, wherein the power supply unit comprises one or more batteries.

18. The system of claim 15, wherein the power supply unit further comprises a solar panel coupled to a solar charging unit, the solar charging unit further coupled to the one or more batteries and configured to charge the batteries using electrical power produced by the solar panel.