A 3.5-GHz band 140-W-class wideband feed-forward power amplifier for mobile base stations

This paper analyzes the characteristics when compensating for wideband intermodulation distortion (IMD) components of a fabricated 3.5-GHz band 140-W class feed-forward power amplifier (FFPA) for mobile base stations. The fabricated FFPA achieves the bandwidths of 160 MHz and 120 MHz when compensating for the IMD components for LTE signals with the bandwidths of 5 MHz and 20 MHz, respectively, when the output power is 40 dBm and the adjacent channel leakage power ratio is -45 dBc. Experimental and analysis results show that the FFPA compensates for the wideband IMD components when the IMD component compensation level is reduced. This paper shows that the FFPA is a worthwhile linearizer that compensates for 3.5-GHz band wideband IMD components.