Broadband Doherty Power Amplifier With Transferable Continuous Mode

In this paper, in-band continuous mode transferring (CMT) method is presented for designing broadband Doherty power amplifier (DPA). Specifically, transferable continuous mode, transferring between class-J continuum to class-F-& x2212;1 continuum, is introduced into DPA at output back-off (OBO) power level for improving bandwidth and efficiency. For validation, a broadband DPA with operation mode transferring from continuous class-J to continuous class-F-& x2212;1 is designed, fabricated and measured. Experimental results show the drain efficiencies (DEs) of the fabricated DPA are 46.3 & x0025;-57.7 & x0025; and 58.4 & x0025;-69.1 & x0025; at 6 dB OBO and peaking power levels over 1.7-2.6 GHz. The saturation power of this DPA is 43.1-45.2 dBm with a gain of 9.1-11.2 dB in the interested band. Furthermore, when the fabricated DPA is stimulated by a 20 MHz wideband signal with a peak-to-average power ratio (PAPR) of 7.05 dB at 2.4 GHz, the measured average power is 36.5 dBm with an average DE of 45.7 & x0025;, and the measured adjacent channel leakage ratios (ACLRs) are & x2212;31.9 dBc and & x2212;50.4 dBc before and after DPD technique, respectively.