To attain a standby function requiring a low power.

A transmission side wireless communication apparatus generates a frame resulting from attaching an advance notice signal to a general wireless frame (preamble + field synchronizing signal + data part) and transmits the resulting frame. The temporal length of the advance notice signal is equivalent to an error time between a synchronizing referencing time of a reception side wireless communication apparatus and a reception timing of the receiver side wireless communication apparatus. Further, a time when the transmission side wireless communication apparatus transmits the frame is equal to a time before a half the error time from the transmission timing. The receiver side wireless communication apparatus determines the presence/absence of the advance notice signal in the reception timing depending on the radio wave strength and activates its reception function when determining the presence of the advance notice signal. Since the receiver side wireless communication apparatus can determine the necessity of activating the reception function in the reception timing, the receiver side wireless communication apparatus can execute waiting with a low power.

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