A method at a sensor module within a sensor system for communicating with a gateway, the method including storing a timing profile for communications with the gateway; waking a radio core of the sensor module at a threshold time prior to a beacon signal being expected from the gateway; sampling a channel for the beacon signal at the radio core; if the beacon signal is detected: waking a processor on the sensor module; exchanging communication with the gateway; and powering down the processor and radio core upon completion of the exchanging communication.