A access point (AP) during wireless communication with at least one wireless transmit/receive unit (WTRU), transmits a beacon signal periodically among a plurality of sectors, each sector having its own sector identity, the beacon signal being periodically received at least once in a beacon period and the beacon period comprising a plurality of beacon service periods for all sectors. The AP determines a scheduling value to indicate a number of inactive beacon periods for a first sector to at least one WTRU located in the first sector. The scheduling value is transmitted with the sector identity for the first sector, such that a variable beacon period is established for the first sector, enabling the at least one WTRU located in the first sector to enter a sleep mode for an adjustable period of time.