Patent ID: 7672649

Claim:
A controller for a radio-frequency (RF) amplifier comprising: an IQ control element, supplied with an RF signal to be amplified, said RF signal having a magnitude and a phase and said IQ control element adjusting said magnitude and phase of said RF signal; said IQ control element containing a signal splitter that splits said RF signal into two partial signals having a 90° phase offset relative to each other, respectively in an I path and a Q path, said I path comprising an I path multiplier that multiplies the partial signal in said I path by an I factor, said Q path having a Q path multiplier that multiplies the partial signal in said Q path by a Q factor, and a summing unit connected to said I path and to said Q path that sums the partial signals after respective multiplication thereof in the I path and the Q path; a detector having a first input to which said RF signal is supplied that is also supplied to said IQ control element, and an input to which an RF signal amplified by the RF amplifier is supplied, said detector determining an actual phase difference and an actual amplification between the respective signals at the first and second inputs; an IQ controller that determines said I factor and said Q factor from said actual phase difference and a desired phase difference and said actual amplification and a desired amplification, said IQ controller having an operating point at which said I factor and said Q factor are equal in magnitude if said actual phase difference and said desired phase difference are equal and said actual amplification and said desired amplification are equal.