End node and network coordinator using a CSMA based protocol

摘要

A communication protocol based on CSMA between a node, in particular an electronic label, and a network coordinator is disclosed. The node comprises:-a transceiver provided for communication with a network coordinator, wherein the transceiver handles a transmission channel based on CSMA;-a processing unit provided for processing data received via the transmission channel and displaying the data on a display unit. The electronic label is arranged to perform:-sending recurrently a data request packet;-going to a low power mode after sending the data request packet; and-waking-up for receiving a data response packet a predefined time interval after beginning sending the data request packet. The network coordinator is arranged to transmit the data response packet the predefined time interval after receiving the beginning of the data request packet. The invention provides a protocol based on CSMA with very low power operation in which a multitude of end nodes could receive from a network coordinator their corresponding data.