COMMUNICATION APPARATUS

PROBLEM TO BE SOLVED: To suppress the increase of transmission latency time caused by an erroneous detection and noise in determination of a carrier when the receiving strength per communication apparatus varies a lot and noise whose strength is larger than the receiving strength is received in the CSMA (Carrier Sense Multiple Access)/CA (Collision Avoidance) access method of the communication apparatus. SOLUTION: A process to compare the receiving strength with a threshold value to decide the carrier and another process to detect a synchronous signal at the head of communication signals are simultaneously operated. A transmission timing control section detects the continuance after the existence of the carrier is decided. If no synchronous detection is detected in a certain time of period after the existence of the carrier is decided, a process to subtract the continuance after the decision of the carrier existence from a CW (Contention Window) period is provided. From the above, the increase of the transmission latency time when a noise larger than the threshold value is received is suppressed. COPYRIGHT: (C)2011,JPO&INPIT