Simultaneous 3rd-and-5th-Order Intermodulation Compensation with Cuber Predistortion and 2nd Harmonics Injection for Microwave Power Amplifiers

A new linearization technique is proposed that compensates 3^rd-and-5^th-order intermodulation distortion (IM3 and IM5) simultaneously by using Cuber Predistortion and 2^nd harmonics injection. Due to the use of predistortion, the power amplifier (PA) can be linearized at lower output back-off values and smaller drain currents than possible with the PA using conventional 3^rd order distortion compensation. To validate the proposed technique, a 2 GHz band 45 W class PA and a linearizer are implemented. Two-tone test results show that both IM3 and IM5 are suppressed over a wide output dynamic range. W-CDMA one-carrier tests show that the ACLR of the PA is also improved, from -49.3 dBc to -62.3 dBc.