Design of a Wideband Doherty Power Amplifier with High Efficiency for 5G Application

Abstract

This paper discusses the design of a wideband class AB-C Doherty power amplifier suitable for 5G applications. Theoretical analysis of the output matching network is presented, focusing on the impact of the non-ideally infinite output impedance of the auxiliary amplifier in back off, due to the device’s parasitic elements. By properly accounting for this effect, the designed output matching network was able to follow the desired impedance trajectories across the 2.8 GHz to 3.6 GHz range (fractional bandwidth = 25%), with a good trade-off between efficiency and bandwidth. The Doherty power amplifier was designed with two 10 W packaged GaN HEMTs. The measurement results showed that it provided 43 dBm to 44.2 dBm saturated output power and 8 dB to 13.5 dB linear power gain over the entire band. The achieved drain efficiency was between 62% and 76.5% at saturation and between 44% and 56% at 6 dB of output power back-off.

A review of Doherty power amplifier and load modulated balanced amplifier for 5G technology

“…The measurement results for Watanabe et al 43 is tabulated in Table 1 along with Kawai et al 46 where both have series DPA structures. In addition, McKnight et al 47 and Nasri et al 48 are some of the recent works that are implemented in the same technology and also their working frequency is close to that of Watanabe et al 43 …”

“…The measurement results for Watanabe et al 43 is tabulated in Table 1 along with Kawai et al 46 where both have series DPA structures. In addition, McKnight et al 47 and Nasri et al 48 are some of the recent works that are implemented in the same technology and also their working frequency is close to that of Watanabe et al 43 F I G U R E 7 Series-type Doherty 30 F I G U R E 8 Microwave GaN HEMT DPA with a series-connected load 26,45 The design that is shown in Figure 9A necessitates a load that needs be driven from two terminals. It is possible to fix this issue by using a balun circuitry; however, it will add extra loss in the output network which results in lower drain efficiency and poor PAE.…”

A Broadband Three-Way Series Doherty Power Amplifier with Deep Power Back-Off Efficiency Enhancement for 5G Application

“…The Doherty power amplifier (DPA) is the most widely used architecture for improving the OBO efficiency of PAs due to its intrinsic linearity and low baseband overhead [8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23]. A DPA typically comprises a Main PA and an Auxiliary PA, with its OBO efficiency enhanced through active load modulation between these two sub-PAs.…”

A Novel Autoregressive Spectral Estimation-Based Neural Network Crest Factor Reduction Structure in Power Amplifiers of 5G Systems in Sandstorm Environment

“…However, for high frequencies, especially in the millimeter region, electromagnetic waves tend to decay rapidly in real-time channels. erefore, massive multiple-input multiple-output (MIMO) has been widely applied in 5G systems, where large scale of antennas, mixers, and power ampli ers have been used [8][9][10][11][12][13]. With the increase of operating frequencies and bandwidth, it is not easy for power ampli ers to achieve high linearity and power e ciency in the whole band.…”