A Reactance Compensated Three-Device Doherty Power Amplifier for Bandwidth and Back-Off Range Extension

الملخص EN

This paper proposes a new broadband Doherty power amplifier topology with extended back-off range.

A shunted λ/4 short line or λ/2 open line working as compensating reactance is introduced to the conventional load modulation network, which greatly improves its bandwidth.

Underlying bandwidth extension mechanism of the proposed configuration is comprehensively analyzed.

A three-device Doherty power amplifier is implemented for demonstration based on Cree’s 10 W HEMTs.

Measurements show that at least 41% drain efficiency is maintained from 2.0 GHz to 2.6 GHz at 8 dB back-off range.

In the same operating band, saturation power is larger than 43.6 dBm and drain efficiency is higher than 53%.