WIRELESS SENSOR NETWORK

• US 20100054307A1
• Filed: 04/17/2009
• Published: 03/04/2010
• Est. Priority Date: 08/27/2008
• Status: Active Grant

• Current Assignee: FW Murphy Production Controls LLC (Waukesha Bearings Corporation)
• Original Assignee: Murphy Industries, Inc.
• Inventors: STROHM, CHARLES FRED
• Granted Patent: US 8,289,184 B2
• Time in Patent Office: Days
• US Class Current: 375/133
• CPC Class Codes: H04Q 2209/40 using a wireless architecture
• CPC Class Codes: H04Q 2209/826 where the data is sent periodically
• CPC Class Codes: H04Q 9/00 Arrangements in telecontrol or telemetry systems for selectively calling a substation from a main station, in which substation desired apparatus is selected for applying a control signal thereto or for obtaining measured values therefrom

Abstract

A system for event monitoring is disclosed. The system includes a remote sensor, a remote transceiver interfaced to the remote sensor, and a base transceiver that selectively wirelessly communicates with the remote transceiver. The remote transceiver provides a periodic communication to the base transceiver that is indicative of a nominal operating condition and the periodic communication is acknowledged by the base transceiver.

Claims

1. A system for event monitoring, comprising:

a remote sensor;

a remote transceiver interfaced to the remote sensor; and

a base transceiver that selectively wirelessly communicates with the remote transceiver;

wherein the remote transceiver provides a periodic communication to the base transceiver that is indicative of a nominal operating condition and the periodic communication is acknowledged by the base transceiver.

2. The system of claim 1, wherein the periodic communication is a packet based communication.

3. The system of claim 2, wherein the periodic communication is frequency shift key (FSK) encoded.

4. The system of claim 3, wherein the periodic communication has a frequency chosen based on a frequency hopping spread spectrum (FHSS) protocol.

5. The system of claim 1, wherein the remote transceiver operates in a first fail safe mode when the periodic communication acknowledgement is not received by the remote, the first fail safe mode comprising changing a channel for receiving the acknowledgement and retransmitting the periodic communication at a higher power than the first transmission of the periodic communication.

6. The system of claim 5, wherein the remote operates in a second failsafe mode when the acknowledgement is not received in the first failsafe mode, the second failsafe mode comprising changing the channel for receiving the acknowledgement and retransmitting the periodic communication on a plurality of channels.

7. The system of claim 6, wherein the remote operates in a third failsafe mode when the acknowledgement is not received in the second failsafe mode, the third failsafe mode comprising changing the channel for receiving the acknowledgement, completing a delay cycle, and transmitting the periodic communication at a higher power than the first transmission of the periodic communication and on a plurality of channels.

8. The system of claim 1, wherein, in response to a sensor event, the remote transceiver immediately transmits to the base transceiver, a packet based communication indicative of a sensor event.

9. The system of claim 8, wherein the packet based communication indicative of a sensor event is transmitted on a default channel monitored by the base transceiver.

10. The system of claim 9, wherein the packet based communication indicative of a sensor event is transmitted via a frequency shift keying (FSK) on a spread spectrum.

11. The system of claim 8, wherein the packet based communication indicative of a sensor event is transmitted on a plurality of channels.

12. A system for real-time event monitoring, comprising:

a plurality of remote transceivers, each connected to at least one sensor, the at least one sensor monitoring a parameter of a monitored system; and

a base station transceiver in periodic wireless communication with each of the remote transceivers;

wherein the periodic communications are via a frequency shift key (FSK) encoded frequency hopping spread spectrum (FHSS) and include scheduled heartbeat communications indicative of nominal remote transceiver operation.

13. The system of claim 12, wherein each of the scheduled heartbeat communications comprise a single remote transmitting to the base station transceiver at a predetermined time and on a predetermined channel.

14. The system of claim 12, wherein each of the scheduled heartbeat communications provides from a transmitting remote transceiver to the base station transceiver a channel on which the base station transceiver will provide an acknowledgement communication.

15. The system of claim 14, wherein each of the remote transceivers will operate in a fail safe mode if the acknowledgement from the base station transceiver is not received.

16. The system of claim 15, wherein the failsafe mode comprises retransmitting the heartbeat communication with a second channel on which the base station transceiver will provide the acknowledgement communication.

17. The system of claim 16, wherein the failsafe mode comprises retransmitting the heartbeat communication at a higher power than the original transmission.

18. The system of claim 16, wherein the failsafe mode comprises transmitting the heartbeat communication on a channel that is different from a channel originally used to transmit the heartbeat communication.

19. The system of claim 16, wherein the failsafe mode comprises transmitting the heartbeat communication on multiple channels.

20. A method of providing substantially real-time, fail-safe operation of a wireless sensor network, comprising:

providing a plurality of remote transceivers, each having at least one attached sensor; and

providing a base station transceiver in selective wireless communication with each of the plurality of remote transceivers;

wherein each of the remote transceivers provides a periodic heartbeat communication to the base station transceiver, the heart beat communication corresponding to an absence of sensor events at a transmitting remote transceiver;

wherein each heartbeat communication is acknowledged by the base station to the transmitting remote transceiver on a channel specified in the heartbeat communication; and

wherein if the acknowledgement is not received by the transmitting remote transceiver, the transmitting remote transceiver will enter a failsafe operation mode, where the heartbeat packet is selectively rebroadcast;

with a changed acknowledgement channel;

at a higher power;

on a different, default channel;

on a plurality of channels; and

on multiple channels.