WIRELESS COMMUNICATION SYSTEM, COMMUNICATION CONTROL METHOD AND COMMUNICATION NODE

PROBLEM TO BE SOLVED: To achieve reduction of power consumption and efficient access control at each of wireless nodes in an electronic tag system and a sensor network system, etc. in which power saving of the wireless node is important. SOLUTION: Each node in wireless communication is synchronized in a period of an AP (active period) for transmitting/receiving data and an iAP (inactive period) for stopping transmission/reception of the data. When a certain node transmits, for example, data with comparatively large data size, the data are transmitted in slots in a plurality of APs. At this time, when a packet is transmitted by a certain slot of a certain AP, information indicating that the data are transmitted also in the same slot of the next AP is inserted into a packet. In addition, the node performs CCA (Clear Channel Assessment) from the head (waiting time w0) of the slot to perform packet transmission only in a slot reserved in advance. COPYRIGHT: (C)2008,JPO&INPIT