Patent ID: 7046974

Claim:
A radio frequency circuit comprising: a radio frequency signal source which produces a radio frequency signal; a power amplifier which power amplifies the radio frequency signal from said radio frequency signal source; and a control unit which controls an output power of said power amplifier; said control unit being configured to hold control data defining a relationship among the operation bias point of said power amplifier and at least two of an input power, a gain, and the output power of said power amplifier and to adjust the operation bias point of said power amplifier based on the control data such that the output power of said power amplifier is set into a level designated by an external power designating instruction; external power designating instruction designates a maximum output power of said power amplifier, said operation bias point is adjusted to a value nearer a class B area than that for the maximum output power within a range that a ratio of an undesired signal component to a desired signal component of the radio frequency signal from said power amplifier is maintained below a distortion reference value specified for a radio communication system, and said control data are referred to for controlling the sum of the input power and the gain of said power amplifier to be equal to the output power of said power amplifier.