Enhanced ZigBee mesh network with dormant mode activation
View Patent ↗A system, apparatus, and method for managing energy conservation in a mesh network of smart container monitoring system is provided. The monitoring unit and the monitored devices within each smart container form a first-tier network, and the smart containers in vicinity are wirelessly connected to form a second-tier mesh network. Each tier of network awakens per a defined procedure to allow for establishment of communication for a short amount of time.
1. A two-tier network system for managing communications among a plurality of shipping containers, the system comprising:
a first-tier network for monitoring communications within a single container, wherein the first-tier network comprises a plurality of monitoring units within the monitored container, wherein the monitoring units comprise a sensor, a sensor manager and a processing unit, further wherein the monitoring units are wirelessly linked to one another, and further wherein at least one monitoring unit is assigned as a coordinating monitoring unit which queries and coordinates activities among the plurality of monitoring units, further wherein the role of the coordinating monitoring unit may be switched between the plurality of monitoring units; and
a second-tier network for coordinating communications between a plurality of containers monitored with first-tier networks, wherein the coordinating monitoring units in each of the plurality of monitored containers is a node of the second-tier network;
wherein the first-tier network is configured to work in a first sleep mode which is managed by the coordinating monitoring unit, wherein the sensor manager of the coordinating monitoring unit manages the wake up and sleep mode activities of the coordinating monitoring unit without waking the processing unit of coordinating monitoring unit; and
the second-tier network is configured to work in a second sleep mode, wherein the second sleep mode is managed by a coordinating monitoring unit.
2. The system of claim 1 , wherein the second sleep mode is independent from the first sleep mode.
3. The system of claim 1 , wherein the first-tier network is a star network or an extended star network.
4. The system of claim 1 , wherein the first-tier network is configured to be awakened on a first configurable interval and stay awake for a first configurable period.
5. The system of claim 1 , wherein during the awake period of the first-tier network, the coordinating monitoring unit is capable of polling the status of the multiple devices and creating messages to be transmitted later.
6. The system of claim 1 , wherein the second-tier network is configured to be awakened on a second configurable interval and at a time with respect to Coordinated Universal Time.
7. The system of claim 1 , wherein the monitoring units are configured to update GPS information during an awake period of the second-tier network.