# Broadband Class-J GaN Doherty Power Amplifier

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## Abstract

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## 1. Introduction

## 2. Theoretical Analysis

#### 2.1. Doherty PA

#### 2.2. Class-J PA

## 3. Class-J DPA Design Strategy

## 4. Simulation Results

## 5. Measurement Results

## 6. Conclusions

## Author Contributions

## Funding

## Conflicts of Interest

## References

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**Figure 2.**Intrinsic main and auxiliary impedances of the DPA class-J at the fundamental and second harmonics when ${R}_{\mathrm{opt}}$ = 50 $\Omega $.

**Figure 4.**(

**a**) Schematic of the OMNs (dimension length and width are in millimeters), and (

**b**) corresponding simulated fundamental and second harmonics load modulation for the main and auxiliary PAs.

**Figure 7.**(

**a**) Simulated IMD3 and IMD5 versus output power. (

**b**) Simulated input (blue) and output (red) spectra at 3.5 GHz.

**Figure 11.**Measured (dashed) and simulated (solid) CW performance of the proposed DPA versus frequency at saturation and at 6 dB OBO: (

**a**) drain efficiency, (

**b**) output power, and (

**c**) gain.

Elements | ${\mathit{L}}_{1}$ | ${\mathit{L}}_{2}$ | ${\mathit{L}}_{3}$ | ${\mathit{C}}_{1}$ | ${\mathit{C}}_{2}$ | ${\mathit{C}}_{3}$ |
---|---|---|---|---|---|---|

Value | 0.75 nH | 0.7 nH | 0.6 nH | 0.2 pF | 0.22 pF | 0.25 pF |

**Table 2.**Comparison of the proposed class-J DPA with the literature: only designs based on the same CGH40010F device are considered.

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**MDPI and ACS Style**

Nasri, A.; Estebsari, M.; Toofan, S.; Piacibello, A.; Pirola, M.; Camarchia, V.; Ramella, C.
Broadband Class-J GaN Doherty Power Amplifier. *Electronics* **2022**, *11*, 552.
https://doi.org/10.3390/electronics11040552

**AMA Style**

Nasri A, Estebsari M, Toofan S, Piacibello A, Pirola M, Camarchia V, Ramella C.
Broadband Class-J GaN Doherty Power Amplifier. *Electronics*. 2022; 11(4):552.
https://doi.org/10.3390/electronics11040552

**Chicago/Turabian Style**

Nasri, Abbas, Motahhareh Estebsari, Siroos Toofan, Anna Piacibello, Marco Pirola, Vittorio Camarchia, and Chiara Ramella.
2022. "Broadband Class-J GaN Doherty Power Amplifier" *Electronics* 11, no. 4: 552.
https://doi.org/10.3390/electronics11040552