To precisely synchronize system clocks, medium clocks, or the like of apparatuses with each other.
A wireless apparatus includes a main control unit and a wireless control unit. Information regarding a correspondence between a clock that manages a time of the main control unit and a clock that manages a time of the wireless control unit is wirelessly sent to another wireless apparatus by the wireless control unit. This information regarding the correspondence includes information regarding a difference between the two clocks, information regarding a granularity ratio of the two clocks, and the like. For example, the wireless control unit sends the information regarding the correspondence as a part of a frame for measuring the time of the wireless control unit with respect to the other wireless apparatus or a part of a frame for connecting to the other wireless apparatus.