Characterization of nonlinearities in a class-J power amplifier

We characterize the nonlinearities of a novel 10 W class-J power amplifier (PA) with a carrier at 1.5 GHz. We employ both numerical simulations and real time adjacent channel power ratio (ACPR) measurements on a fabricated prototype. The measurements are performed for a wideband code division multiple access (WCDMA) signal with 10.5 dB peak-to-average power ratio (PAPR) and 3.84 MHz bandwidth. For a 31.4 dBm modulated output power, the measured ACPR in the lower and upper adjacent channels was 37.89 dBc and 36.82 dBc, respectively, without predistortion.