Using inactivity levels to extend subscriber equipment battery life

A method for extending battery life in a subscriber unit having a battery backup power supply using a smart battery and communicating with a system node of a wireless communication network, the method comprising the steps of:

• establishing a current inactivity level;
• determining a status of a smart battery;
• performing an inactivity level registration with a system node requesting to use an inactivity level associated with the status of the smart battery;
• and
• setting the inactivity level in accordance with a response from the system node.

A subscriber unit in a wireless communications system for providing extended battery life, the subscriber unit comprising:

• a battery for supplying power to the subscriber unit;
• a cellular transceiver;
• a processor connected to the transceiver;
• and
• a memory connected to the processor, the memory comprising instructions for:
• establishing a current inactivity level;
• performing an incremental inactivity level registration with a system node requesting to use a next highest inactivity level when line power for supplying power to the subscriber unit is absent and setting the inactivity level in accordance with a response from the system node.