A method, system, and apparatus for adjusting the headroom for a received
signal in a radio receiver when the received signal includes a target
signal and an interference signal. An amplifier coupled with the received
signal outputs an amplified signal, and the amplification level of the
amplifier is set by an amplification control signal. An analog-to-digital
converter converts the amplified signal to a digital signal. A first
digital filter is used to filter the digital signal at a first
attenuation factor and produces a first filter output coupled with the
amplification control signal. The first filter output is proportional to
the magnitude of the interference signal when the interference signal is
greater in magnitude than the target signal. A second digital filter is
used to filter the digital signal at a second attenuation factor.