A 2.4-GHz CMOS Power Amplifier With an Integrated Antenna Impedance Mismatch Correction System

To prevent the performance degradation of a power amplifier (PA) from an antenna impedance mismatch, we propose a fully integrated PA with an automatic antenna-mismatch correction system. Using only voltage amplitude information, this method reduces the complexity of the system while compensating impedance mismatch at all mismatched impedance angles. The proposed PA is implemented in 0.18- μm CMOS technology and the measurement results show it maintains its 1-dB gain variation point as well as power-added efficiency under the mismatched condition close to that of a well-matched condition. To the best of our knowledge, this is the first fully integrated CMOS PA that is capable of automatically recovering antenna-mismatch conditions without any help from the off-chip components.