scholarly journals Design and analysis of 80-W wideband asymmetrical Doherty amplifier

Author(s):  
Khaled Bathich ◽  
Georg Boeck

This paper presents the analysis and design of a wideband asymmetrical Doherty amplifier. The frequency response of the output combining network of the Doherty amplifier with arbitrary back-off level configuration is analyzed. Other bandwidth-limiting factors were discussed and analyzed as well. A number of performance enhancement techniques were taken into consideration to obtain high and flat back-off efficiency over the amplifier design band of 1.7–2.25 GHz. The designed Doherty amplifier had, at 8.0–9.9 dB output back-off, a minimum efficiency of η = 50% [power-added efficiency of 45%], measured near 40 dBm of output power, and over 28% bandwidth. Using digital predistortion (DPD) linearization, an adjacent-channel leakage ratio (ACLR) of −43 dBc was obtained for a single-carrier W-CDMA signal, at 40.9 dBm and 46% of average output power and drain efficiency, respectively. The designed amplifier represents the first wideband Doherty amplifier reported over extended power back-off range.

2012 ◽  
Vol 4 (6) ◽  
pp. 559-567 ◽  
Author(s):  
Ahmed Sayed ◽  
Sebastian Preis ◽  
Georg Boeck

In this paper, a 10 W ultra-broadband GaN power amplifier (PA) is designed, fabricated, and tested. The suggested design technique provides a more accurate starting point for matching network synthesis and better prediction of achievable circuit performance. A negative-image model was used to fit the extracted optimum impedances based on source-/load-pull technique and multi-section impedance matching networks were designed. The implemented amplifier presents an excellent broadband performance, resulting in a gain of 8.5 ± 0.5 dB, saturated output power of ≥10 W, and power added efficiency (PAE) of ≥23% over the whole bandwidth. The linearity performance has also been characterized. An output third-order intercept point (OIP3) of ≥45 dBm was extracted based on a two-tone measurement technique in the operating bandwidth with different frequency spacing values. The memory effect based on AM/AM and AM/PM conversions was also characterized using a modulated WiMAX signal of 10 MHz bandwidth at 5.8 GHz. Furthermore, a broadband Wilkinson combiner was designed for the same bandwidth with very low loss to extend the overall output power. Excellent agreement between simulated and measured PA performances was also achieved.


2010 ◽  
Vol 2 (1) ◽  
pp. 95-104 ◽  
Author(s):  
Dirk Wiegner ◽  
Gerhard Luz ◽  
Patrick Jüschke ◽  
Robin Machinal ◽  
Thomas Merk ◽  
...  

This paper gives a summarized overview on the progress and achievements on AlGaN/GaN high electron mobility transistors (HEMT)-based power amplifiers (PAs) for mobile radio applications which have been achieved within two national funded German projects during a period of six years. Starting with a first 34 dBm (2.5 W, peak) amplifier in 2003 the impressive progress toward highly efficient S-band mobile radio PAs with up to >50 dBm (100 W) peak output power is described by means of some selected single- and multiband amplifier demonstrators. This progress has been mainly enabled by clear progress on GaN technology, device packaging, and PA design. Targeting at highly efficient single-band amplifier applications, a 2.7 GHz symmetrical Doherty amplifier with up to 45% drain efficiency at close to 45 dBm average output power under single-carrier W-CDMA (Wideband Code Division Multiple Access) operation using digital predistortion can be highlighted. In case of multiband capable amplifiers addressing software-defined radio applications, a class-AB-based demonstrator covering a frequency range from 1.8 to 2.7 GHz was realized. The amplifier showed >30% drain efficiency up to 2.5 GHz as well as up to 40 dBm average output power under single-carrier W-CDMA operation using proprietary digital predistortion. Finally, Alcatel-Lucent's activities on envelope tracking for future efficiency improved GaN-based amplifiers are described.


Frequenz ◽  
2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Saeedeh Lotfi ◽  
Saeed Roshani ◽  
Sobhan Roshani ◽  
Maryam Shirzadian Gilan

Abstract This paper presents a new Doherty power amplifier (DPA) with harmonics suppression. A Wilkinson power divider (WPD) with open-ended and short-ended stubs is designed to suppress unwanted signals. To design the power divider in the circuit of the DPA, even and odd mode analyses are utilized. The proposed design operates at range of 1.2–1.6 GHz. The linearity of the suggested DPA is increased about 6 dBm, in comparison with the main amplifier. The designed Doherty amplifier has a power added efficiency (PAE), drain efficiency (DE) and Gain about 60, 61% and 19 dB, respectively. The designed WPD suppresses 2nd up to 14th harmonics with more than 20 dB suppression level, which is useful for suppressing unwanted harmonics in DPA design. ATF-34143 transistors (pHEMT technology) are used for this DPA amplifier design. The main amplifier has class-F topology and class-F inverse topology is used for auxiliary amplifier.


2018 ◽  
Vol 10 (4) ◽  
pp. 391-400 ◽  
Author(s):  
Xuekun Du ◽  
Chang Jiang You ◽  
Yulong Zhao ◽  
Xiang Li ◽  
Mohamed Helaoui ◽  
...  

ABSTRACTAn analytical method is proposed to reduce the memory effects and third-order intermodulation distortions for improving the linearity of wideband power amplifier (PA). An excellent linearity can be obtained by reducing the second-harmonic output power levels and reducing the envelope voltage components in the megahertz range. An improved wideband Chebyshev low-pass matching network including the bias network is analyzed and designed to validate the proposed method. The measured results indicate that a wideband high-efficiency linearized PA is realized from 1.35 to 2.45 GHz (fractional bandwidth = 58%) with power added efficiency of 60–78%, power gain of 10.8–12.3 dB, and output power of 40.0–41.2 dBm. For a 20 MHz LTE modulated signal, the adjacent channel leakage ratios (ACLRs) of the proposed PA with digital pre-distortion (DPD) linearization are −55.7 ~ −53.9 dBc across 1.5–2.4 GHz at an average output power of 32.4–33.6 dBm. For a 40 MHz two-carrier LTE modulated signal, the ACLRs of the proposed PA with DPD linearization are −51.1 ~ −48.2 dBc at an average output power of ~30.5 dBm in the frequency range from 1.5 GHz to 2.4 GHz.


Electronics ◽  
2019 ◽  
Vol 8 (6) ◽  
pp. 621
Author(s):  
Tao Cao ◽  
Youjiang Liu ◽  
Wenhua Chen ◽  
Chun Yang ◽  
Jie Zhou

An analytical method to design a power amplifier (PA) with an optimized power added efficiency (PAE) trajectory for envelope tracking (ET) architecture is proposed. To obtain feasible matching solutions for high-efficiency performance of the PA in the dynamic supply operation, hybrid continuous modes (HCM) architecture is introduced. The design space for load impedances of the HCM PAs with nonlinear capacitance is deduced mathematically using the device’s embedding transfer network, without the necessity of using load-pull. The proposed design strategy is verified with the implementation of a GaN PA operating over the frequency range of 1.9 GHz to 2.2 GHz with PAE between 67.8% and 72.4% in the 6.7 dB back-off power region of the ET mode. The ET experimental system was set up to evaluate the application of the PA circuit. Measurement results show that the ET PA at 2.1 GHz reaches the efficiency of 61%, 54%, 44% and an error vector magnitude (EVM) of 0.32%, 0.60%, 0.67% at an average output power of 34.4 dBm, 34.2 dBm, 34.1 dBm for 6.7 dB peak-to-average power ratios (PAPR) signals with 5 MHz, 10 MHz, and 20 MHz bandwidths, respectively. Additionally, tested by a 20 MHz bandwidth 16 quadrature amplitude modulation (QAM) signal, 41.8% to 49.2% efficiency of ET PA is achieved at an average output power of 33.5 dBm to 35.1 dBm from 1.9 GHz to 2.2 GHz.


2014 ◽  
Vol 23 (08) ◽  
pp. 1450113 ◽  
Author(s):  
MOHAMMAD MOGHADDAM TABRIZI ◽  
NASSER MASOUMI

In this work, a novel and efficient approach is proposed to optimize linearity and efficiency of a power amplifier used in mobile communication applications. A linear and high performance push amplifier is designed and analyzed to extract design equations for an optimum performance. The proposed push amplifier has two sections; an analog section and a switching section. The analog section provides the required linearity and the switching section guarantees the satisfaction of the total efficiency level. Double power supply scheme is used in push amplifiers to enhance its performance. Two separate power supplies are employed for linear and switching sections of push amplifiers which have different voltage levels. The implemented circuit is simulated using HSPICERF with TSMC models for active and passive elements. The proposed power amplifier (PA) provides a maximum output power of 25 dBm and power added efficiency (PAE) as high as 51% at 2.5 GHz operation frequency. At 1-dB compression point, this PA exhibits output power of 25 dBm with 48% PAE and 4.5% error vector magnitude (EVM) which is appropriate for 64QAM OFDM signals.


2018 ◽  
Vol 10 (9) ◽  
pp. 999-1010 ◽  
Author(s):  
Michele Squartecchia ◽  
Tom K. Johansen ◽  
Jean-Yves Dupuy ◽  
Virginio Midili ◽  
Virginie Nodjiadjim ◽  
...  

AbstractIn this paper, we report the analysis, design, and implementation of stacked transistors for power amplifiers realized on InP Double Heterojunction Bipolar Transistors (DHBTs) technology. A theoretical analysis based on the interstage matching between all the single transistors has been developed starting from the small-signal equivalent circuit. The analysis has been extended by including large-signal effects and layout-related limitations. An evaluation of the maximum number of transistors for positive incremental power and gain is also carried out. To validate the analysis, E-band three- and four-stacked InP DHBT matched power cells have been realized for the first time as monolithic microwave integrated circuits (MMICs). For the three-stacked transistor, a small-signal gain of 8.3 dB, a saturated output power of 15 dBm, and a peak power added efficiency (PAE) of 5.2% have been obtained at 81 GHz. At the same frequency, the four-stacked transistor achieves a small-signal gain of 11.5 dB, a saturated output power of 14.9 dBm and a peak PAE of 3.8%. A four-way combined three-stacked MMIC power amplifier has been implemented as well. It exhibits a linear gain of 8.1 dB, a saturated output power higher than 18 dBm, and a PAE higher than 3% at 84 GHz.


2018 ◽  
Vol 2018 ◽  
pp. 1-5 ◽  
Author(s):  
Zhipeng Qin ◽  
Guoqiang Xie ◽  
Jian Zhang ◽  
Jingui Ma ◽  
Peng Yuan ◽  
...  

We report on a continuous-wave (CW) and passively Q-switched Er:Y2O3 ceramic laser in mid-infrared spectral region. In the CW regime, a maximum output power of 2.07 W is achieved at 2717.3 nm with a slope efficiency of 13.5%. Stable passive Q-switching of the Er:Y2O3 ceramic laser is demonstrated based on semiconductor saturable absorber mirror. Under an absorbed pump power of 12.4 W, a maximum average output power of 223 mW is generated with a pulse energy of 1.7 μJ and a pulse width of 350 ns at 2709.3 nm.


Sign in / Sign up

Export Citation Format

Share Document