Asset monitoring system and associated method

Claims

That which is claimed is:

1. An asset monitoring system comprising:

a central station;

at least one asset monitor associated with a respective container for providing said central station with information relating to the respective container, wherein said at least one asset monitor comprises:

an energy storage reservoir which as recharged by energy received from an external power source during tethered periods in which said asset monitor is electrically tethered to the external power source, wherein said energy storage reservoir is adapted to supply energy to maintain said asset monitor in operation during both tethered periods in which said energy storage reservoir is recharged by the external power source and untethered periods in which said asset monitor is electrically untethered from the external power source; and

a controller for controlling operations of said asset monitor, wherein said controller comprises;

tether status determining means for separately identifying tethered periods and untethered periods; and

power management means, responsive to said tether status determining means, for placing said asset monitor in an active mode during tethered periods and an energy conservation mode during untethered periods, wherein said power management means manages recharging of said energy storage reservoir during the active mode, and wherein said power management means selectively permits power to be drawn from said energy storage reservoir during the energy conservation mode, thereby allowing at least some of the operations of said asset monitor to be performed during the energy conservation mode;

a sensor interface, operably connected to said controller, for communicating with at least one sensor which is associated with the container, wherein said power management means only provides power to the at least one sensor for predetermined periods of time during the energy conservation mode such that communication is only established between said controller and the at least one sensor within the predetermined periods of time during the energy conservation mode; and

communications means for establishing a first communications link between said at least one asset monitor and said central station.

2. An asset monitoring system according to claim 1 wherein the at least one sensor is adapted to provide a predetermined type of sensory signal, and wherein said communications means is adapted to transmit information related to the sensory signal to the central station via the first communications link.

3. An asset monitoring system according to claim 2 wherein said