A wireless data communication system is operable in a power saving mode
wherein stations are synchronized to be in an awake state to receive
synchronizing messages (TIM, PSYNC) and traffic indicator information and
are changed to a doze state if they are not to receive data messages. In
one embodiment all stations (20) communicate via a base station access
point (16), which broadcasts synchronizing messages (TIM) at regular
intervals identifying stations (20) that are to receive data messages. In
another embodiment all stations (220) communicate directly with one
another, one station assumes the role of a master station and broadcasts
synchronizing messages (PSYNC), and stations (220) desiring to transmit
data messages transmit traffic indicator messages (PTIM) to the
appropriate destination stations (220), in a synchronized awake period
just before the next synchronizing message (PSYNC) is expected to arrive.