Method and apparatus for maintaining synchronization in a CDMA
communication system by operating closed loop timing control between a
radio base unit and subscriber units, operating open loop timing control
between the radio base unit and the subscriber units, and using timing
information derived from the open loop to correct the closed loop.
Generally the open loop is faster in response than the closed loop. The
open loop timing control may be generated by using GPS data. A radio base
station and a subscriber unit operating in accordance with these
principles.
