METHOD AND APPARATUS OF GLOBAL FRAME COUNTING FOR SYNCHRONIZATION IN SLEEP MODE OF BROADBAND WIRELESS ACCESS SYSTEM

A method and an apparatus of a global frame counting for synchronization in the sleep mode of a broadband wireless access system is provided to reduce a time taken to get into the sleep mode in OFDMA(Orthogonal Frequency Division Multiple Access) based system. An apparatus of a global frame counting for synchronization in the sleep mode of a broadband wireless access system includes a sleep controller(315), a VIC(Vectored Interrupt Controller)(305), a synchronization controller(325), and a clock generator(320). The sleep controller counts with low frequency clock. If the counting result is same with a sleep cycle from a CPU(330), the sleep controller transmits interrupt to the VIC to wake the CPU from sleep mode and transmits frame count result in Modulo 5ms with low frequency clock until a terminal wakes up. The synchronization controller controls each module and maintains synchronous through Modulo 5ms frame counting. The clock generator provides each module with a frequency clock required for each module.