A system, method, and apparatus for establishing headroom for a mobile
station operating in a wireless communication system by determining (230)
a communication channel variance condition and establishing (245) a
headroom value based on the communication channel variance condition. The
headroom value may be further revised by determining (260) if a battery
condition in a mobile station relates to a low battery level and
increasing (265) the headroom value in order to decrease the maximum data
rate. Modifications to headroom allow data rates to be tailored to
specific channel variance conditions and battery conditions.