Time slot allocation method for reduction of energy losses in wireless sensor network

PURPOSE: A time slot allocation method for reduction of energy losses in a wireless sensor network is provided to confirm the length of data and the existence of the data transmitted or received to and from at least one lower node in order to maximize the energy saving. CONSTITUTION: An upper node transmits and receives a report to and from at least one lower node to confirm whether or not data are exchanged between the lower nodes(605), and transmits the information necessary for the transmission of data to at least one lower node(607). The upper node transmits and receives data to and from the lower node(615).