A wireless communication method and system for controlling the current
data bit rate of a radio link (RL) to maintain the quality of the RL. The
system includes a core network (CN), a radio network controller (RNC) and
at least one wireless transmit/receive unit (WTRU). The RL is established
between the RNC and the WTRU. The RNC establishes a guaranteed data bit
rate, a maximum data bit rate and a current data bit rate associated with
the RL. When the RNC senses an event which indicates that the quality of
the RL has substantially deteriorated, the RNC reduces the value of the
current data bit rate. Then, in a recovery process, if a similar event
does not occur during an established waiting period, the RNC restores the
current data bit rate back to the maximum data bit rate.