An efficiency-improved power amplifier using split-ring resonator defected ground structure

This paper reports the effects of split-ring resonator defected ground structure (SRR DGS) on the output power and efficiency of a class C power amplifier. In order to evaluate the effects of SRR DGS on the efficiency and output power, two class C GaAs FET amplifiers have been measured at 0.86~1.0 GHz. One of them has a SRR DGS microstrip line at the output section, while the other has only 50 Ω straight line. Measured results show that SRR DGS rejects the second harmonic at the output and yields improved output power by 1-5%.