Patent ID: 8099074

Claim:
A method for wireless transmission of data between components of a blood glucose system including a master controller having a receiver and a transmitter, and a slave device comprising an insulin dispensing means and having a receiver and a transmitter, the method comprises the following steps: operating the slave device normally in a power saving mode in which its receiver is activated intermittently at a receiver activation frequency, with the receiver each time being activated for a predetermined listening period and the receiver being deactivated for the rest of the time, activating the transmitter of the controller for a transmission period to transmit a communication initiation data frame including a preamble portion which is chosen such that a preamble signal is transmitted for a preamble period, and subsequently activating the receiver of the controller for a response period, and in case the slave device receives the preamble signal during a listening period, a) maintaining the receiver of the slave device active until at least a portion of the remainder of the communication initiation data frame has been received, b) switching the slave device to a communication mode in which the transmitter of the slave device is activated to transmit a response to the controller, and c) switching the slave device from the communication mode to the power saving mode, initially setting the receiver activation frequency to a first frequency value upon switching from communication mode to power saving mode, and setting the receiver activation frequency to a second frequency value smaller than the first frequency value if no communication initiation data frame is received for a predetermined power saving timeout period, wherein the communication initiation data frame is transmitted such that the preamble period exceeds the length of the cycle duration corresponding to the first frequency value, and, in case no response is received by the controller during the response period, the communication initiation data frame is adapted and retransmitted such that the preamble period is increased and exceeds the length of the cycle duration corresponding to the second frequency value.