Linearity improvement of a dual-band Doherty power amplifier using E-CRLH transmission line

Abstract

Abstract A dual-band Doherty power amplifier (DB-DPA) using the extended composite right and left handed transmission lines (E-CRLH TL) is proposed. In this structure the λ / 4 transmission lines are replaced with open-ended E-CRLH TL. The power amplifier exhibits dual-band property at f 1 = 2.5 G H z , f 2 = 3.4 G H z input frequencies and suppresses the second harmonics ( 2 f 1 , 2 f 2 ) at the amplifier output. The simulation studies show that the second harmonic and second order intermodulation (IM2) of the proposed DB-DPA are improved compare to the conventional DPA. This improvement is obtained because of the quad band property of E-CRLH transmission lines. Then, the proposed DB-DPA is examined using various multi tones signals. The better ACPR and efficiency are achieved compare to the conventional Doherty power amplifiers. The measurement results confirm the accuracy of the simulation results.