This paper proposes Reconfigurable Doherty Amplifier (RDA) with Reconfigurable Doherty Coupler.
In case of N-stage RDA, carrier amplifier input signal has a phase delayed by 90 degrees, and there is no phase delay on the inputs of the (N-1) peaking a...
This paper proposes Reconfigurable Doherty Amplifier (RDA) with Reconfigurable Doherty Coupler.
In case of N-stage RDA, carrier amplifier input signal has a phase delayed by 90 degrees, and there is no phase delay on the inputs of the (N-1) peaking amplifier. By preserving a maximum phase delay of 90 degrees, the additional input and output phase delay element associated with N-stage CDA (Conventional Doherty Amplifier) system to accommodate up to 90×(N-1) degrees of phase delay are removed. As a result, in case of WCDMA 1FA signals, 3-stage RDA obtained a measured 51.3dBm output power. An efficiency of 24.7% is achieved at 6.5dB back-off point. A gain is more than 8dB, ACLR (Adjacent Channel Leakage Ratio) is less than -30dBc at 6.5dB back-off point. Thus ACLR is satisfied with 3GPP (3rd Generation Partnership Project) specification in case of using additional linearizer.