The frequencies and the phases of frame timing signals are synchronized between a display apparatus and shutter glasses through a wireless network.The display apparatus counts a frame period and a period until the frame timing signal transitions next time after a beacon transmission timing using a TSF clock and transmits a synchronization packet in which these periods are described. On a shutter glasses side, when the synchronization packet has been received, the frequencies are synchronized on the basis of a difference between frame periods measured by both of them. In addition, phase control is performed on the basis of a difference between periods until next frame timing signals after a beacon is transmitted, which are measured by both of them.