A radio frequency receiver includes an amplifier and a detector that
produces a bias control signal based on a signal environment. A bias level
of the amplifier is set according to the bias control signal. Bias levels
of other receiver circuits may have similarly adjusted bias levels,
including buffers, IF oscillators, mixers, and converters. The invention
can be used to increase range of linearity, intermodulation immunity and
reduce power consumption by reducing the bias level under typical
conditions and relying on the bias control to increase bias levels under
adverse signal conditions. The invention has advantages where power is at
a premium, particularly when a device is in standby mode, including
mobile, portable and hand held pagers and wireless telephones and Internet
connections. If standby mode operation in non-maximum signal environments
dominates the usage of the receiver, then the invention can substantially
increase battery life.
