Patent ID: 8588119

Claim:
A method for wirelessly transferring data between nodes, the method comprising: periodically waking a receiving node from a sleep mode to a receive mode and returning the receiving node to the sleep mode, wherein, in the receive mode, the receiving node samples a plurality of wake-up channels; beginning to transmit at least one wake-up preamble packet by a transmitting node on at least one of the plurality of wake-up channels; receiving, by the receiving node while in the receive mode, a portion of the wake-up preamble packet that the transmitting node has transmitted, the transmitting including estimating a time when the receiving node will awake from the sleep mode to the receive mode and transmitting the at least one wake-up preamble packet to be received by the receiving node while the receiving node is in the receive mode, the estimating including receiving an acknowledgement signal from the receiving node to thereby determine a sleep interval of the receiving node; transmitting, by the receiving node and responsive to receiving the portion of the wake-up preamble packet, an acknowledgement; ceasing of the transmitting of the preamble packet, the ceasing being responsive to receiving the acknowledgment and the ceasing occurring before the preamble packet has been completely transmitted; transmitting, by the transmitting node and responsive to receiving the acknowledgement, a data frame on at least one data channel; and receiving, by the receiving node, the data frame.