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Breaking Bandwidth Limit: A Review of Broadband Doherty Power Amplifier Design for 5G

T0 review · 0 major / 5 minor · reviewed 2026-08-14 · deepseek-v4-flash

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Pith's one-line read The Doherty amplifier's bandwidth bottleneck is a single quarter-wave transmission line, the impedance inverter TL1.

desk verdict A useful, well-organized review of broadband Doherty PA techniques; the tutorial math is standard but clean, and the survey is the real value. read the letter →

arxiv 1908.07755 v1 pith:Y6TCLT6V submitted 2019-08-21 eess.SP

Gholamreza Nikandish , Robert Bogdan Staszewski , Anding Zhu This is my paper · ORCID
classification eess.SP
keywords Dohertypoweramplifierbandwidthenhancementloadmodulationimpedanceinverter5Gtransmittersdesignmm-waveICGaN
verification ladder T0 review T1 audit T2 compute T3 formal

The pith

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The reading

This review paper argues that the classical Doherty power amplifier's intrinsic bandwidth limit has a single dominant source: the quarter-wavelength impedance inverter TL1 in the output network, whose impedance transformation ratio changes from 1 at peak power to 4 at 6-dB back-off. The paper derives the frequency-dependent impedance seen by the carrier amplifier and shows that the back-off impedance supports only about 38% fractional bandwidth for a 20% drop in its real part, which roughly corresponds to 1 dB of output power loss. It then surveys the principal bandwidth-extension techniques reported in the literature, including modified transmission-line impedances, two-section peaking networks, short-circuited stubs, frequency-response optimization, parasitic compensation, post-matching, distributed and dual-input architectures, and transformer-based or transformer-less load modulation. The paper further claims that these techniques mostly work in discrete GaN designs below 4 GHz, while integrated RF and mm-wave implementations remain limited by parasitic capacitances, losses, and layout constraints, so the path to 5G Doherty amplifiers still requires new IC-oriented design methods.

What carries the argument

The central object is the quarter-wavelength transmission-line impedance inverter TL1 with characteristic impedance Z1 = Ropt. The paper models the impedance presented to the carrier amplifier by Zc(f) = Ropt (k + j tan(pi/2 * f/f0)) / (1 + j k tan(pi/2 * f/f0)), where k = 1 at peak power and k = 0.5 at 6-dB back-off, and uses the real part's frequency roll-off as the bandwidth metric. The mechanism doing the argumentative work is the impedance transformation ratio: TL1 acts as a 1:1 transformer at peak power and a 4:1 transformer at back-off, and a transmission-line transformer's bandwidth shrinks as its ratio grows. The derivation also introduces the parameter m = sqrt(Ropt / (2*RL)) to quantify how TL2's transformation ratio (2*RL/Ropt) further constrains bandwidth, and uses fractional bandwidth at 20% real-impedance reduction as the quantitative comparison baseline across designs.

What would settle it

Build or simulate a symmetric 6-dB Doherty PA with the stated Z1 = Ropt and Z2 = sqrt(RL*Ropt/2), bias the peaking device in class-C, and measure the real part of the impedance presented to the carrier device at back-off across frequency. If the frequency at which this impedance falls by 20% implies a fractional bandwidth substantially different from 38%, or if the back-off bandwidth proves to be set by TL2 or the peaking output impedance rather than TL1, the paper's central quantitative claim would be refuted.

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Extended reading notes

Core claim

The central claim is that in a symmetric Doherty power amplifier, the back-off bandwidth is set by the impedance inverter TL1, not by the output matching line TL2 in the usual design. With characteristic impedances Z1 = Ropt and Z2 = sqrt(RL*Ropt/2), TL1 transforms its load by a ratio of 1 at peak power and 4 at 6-dB back-off, which the paper identifies as the main bandwidth constraint. The derived normalized impedance Zc(f) = Ropt (k + j tan(pi/2 * f/f0)) / (1 + j k tan(pi/2 * f/f0)), with k = 1 at peak power and k = 0.5 at 6-dB back-off, shows that the real part of the carrier impedance at back-off falls by 20% over a fractional bandwidth of about 38% for m = 1, while the peak-power impedance stays much flatter. Replacing TL2 with a two-section transformer restores 38% bandwidth for all values of m, and choosing m > 1 (for example with GaN devices having large Ropt) can widen back-off bandwidth to 62% at m = 1.5, at the cost of extra peaks in the peak-power impedance. The paper also claims that a higher-order matching network cannot simply replace TL1 because an impedance inverter must keep its inverse relationship between input and load impedance.

Load-bearing premise

The load-bearing premise is that at 6-dB back-off the peaking amplifier behaves as a perfect open circuit and at peak power as an ideal current source, and that all transmission lines are lossless; if the peaking transistor's real output impedance at back-off is not negligible, the derived impedances and the 38% bandwidth limit will not hold quantitatively.

Editorial extensions

If this is right

  • If back-off bandwidth is governed by TL1's 1-to-4 transformation ratio, then broadband DPA designs should focus on reducing that ratio or compensating its frequency dependence, not on widening TL2.
  • The m-parameter analysis implies that transistors with larger optimum load resistance, such as GaN devices, can push back-off bandwidth from 38% toward 62%, while small-Ropt CMOS devices will inherently have narrower load-modulation bandwidth.
  • Replacing TL2 with a multi-section transformer can recover the ideal 38% back-off bandwidth for arbitrary m, but the impedance inverter TL1 cannot be similarly replaced by a higher-order matching network.
  • Parasitic-absorption techniques, such as reduced-length or lumped-element transmission lines, absorb the drain-source capacitance only at one frequency and degrade bandwidth, so true wideband IC DPAs must use other compensation, post-matching, or dual-input strategies.
  • Among the reviewed techniques, dual-input digital control achieves octave bandwidth (1-3 GHz, 100%) in a reported GaN design, indicating that frequency-dependent input drive can compensate what the output network cannot.

Reading between the lines

Editorial extensions of the paper, not claims the author makes directly.

  • My inference: if the peaking amplifier's finite output conductance at back-off were included in Eq. (3), the 38% figure would likely shrink or shift, making the review's quantitative limits optimistic for real transistors; a direct re-derivation with a shunt conductance would test this.
  • My inference: the same ratio-based reasoning could be applied to asymmetric DPAs, where the paper notes the transformation ratio grows to (N+1)*RL/Ropt for an N-times peaking device, so the bandwidth penalty of higher-PAPR operation is likely even steeper than the symmetric 6-dB case suggests.
  • My inference: the surveyed techniques are mostly demonstrated in discrete GaN at sub-4 GHz; extending them to mm-wave ICs may require lumped-element equivalents of TL1, and the paper's claim that lumped-element inverters are narrowband suggests a fundamental trade-off that future work must break, for instance by nonreciprocal or active load modulation.
  • My inference: a testable prediction follows from the paper: DPA designs with m = 1 should cluster near the 38% back-off bandwidth bound unless they employ one of the surveyed compensation techniques, so a meta-analysis of reported designs could check whether the derivation explains observed bandwidths.
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Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, and a circularity audit.

Referee Report

0 major / 5 minor

Summary. The manuscript is a review and tutorial on bandwidth-extension techniques for Doherty power amplifiers (DPAs) targeting 5G applications. Section II derives the main bandwidth limitation of the classical DPA from the impedance presented to the carrier amplifier, identifying the impedance inverter TL1 as the principal back-off bandwidth limiter and quantifying a 38% fractional bandwidth for a 20% reduction in the real part of the back-off impedance. Section III surveys modified load-modulation networks, frequency-response optimization, parasitic compensation, post-matching DPAs, distributed DPAs, dual-input DPAs, and transformer-based/transformer-less load-modulated PAs, with a comparative performance table. Section IV discusses integrated-circuit implementation challenges and reviews RF and mm-wave IC DPAs, and Section V offers conclusions about the most promising techniques for IC integration.

Significance. If the claims hold, the paper provides a useful structured map of the broadband-DPA field and a compact quantitative account of why the DPA back-off bandwidth is dominated by the impedance inverter TL1. The tutorial derivations are standard and internally consistent, the survey table is informative, and the critical discussion of each technique's drawbacks is a valuable feature. The treatment of IC and mm-wave implementations is a strength, and the authors are careful to flag assumptions (ideal peaking open/current source, lossless transmission lines) and to point out where published bandwidths come with efficiency ripple. No original measurements are presented, but none are required for a review of this type.

minor comments (5)
  1. [Section II-A, after Eq. (5)] The sentence stating that the impedance transformation ratio of TL1 at back-off is (N+1)RL/Ropt is inconsistent with the impedances defined just above it: TL1 transforms Ropt/(N+1) to (N+1)Ropt, so its back-off ratio is (N+1)^2 (equal to 4 for N=1), whereas (N+1)RL/Ropt is the ratio for TL2. Please correct the formula and the surrounding wording.
  2. [Table I caption] The symbols ηPP and ηBO are used in the table but are not defined in the caption; please define them as drain efficiency at peak power and at back-off, and state that the bandwidth values are fractional bandwidths.
  3. [References [13] and [39]] The reference formatting is malformed in two places: [13] gives page numbers '505507' instead of '505–507', and [39] contains a duplicated/confused citation string ('pp. 1–14, 2017. vol. 64, no. 7, pp. 1758–1771'); please correct both entries.
  4. [Section II-B] For the lumped-element equivalent circuit in Fig. 5(b), the bound is given as Cds < C = 1/(Z0ω0); please explicitly identify Z0 and ω0 in the text or figure caption so that the condition is self-contained.
  5. [Section III-A2, discussion of [18]] The sentence 'the impedance transformation ratio is 2 in both cases' would be clearer if the two load impedances (100 Ω and 50 Ω) were named explicitly, since the definition of transformation ratio is not repeated in that paragraph.

Circularity Check

0 steps flagged · score 0.0 of 10

No significant circularity: the tutorial derivation is self-contained standard transmission-line analysis and the review's claims rest on external literature.

full rationale

The paper's central quantitative content, Section II-A, derives the carrier impedance Zc(f) from the classical quarter-wave transmission-line equation with Z1 = Ropt, Z2 = sqrt(RL Ropt / 2), k = 1 at peak power and k = 0.5 at back-off. The resulting Eqs. (3)-(4) and the stated 38% fractional bandwidth are computed from these standard assumptions, not fitted to data and not imported from the authors' own prior results. The review's organizing taxonomy is supported by external literature measurements tabulated in Table I; the self-citations ([45], [55], [56], and [37]) appear only as background references or as one entry in the survey and do not supply the derivation's premises. The idealizations used in the derivation, such as an open-circuit peaking amplifier at back-off and lossless transmission lines, are explicitly stated and subsequently relaxed in Sections II-B and III-C, so the simplification is disclosed rather than hidden. No prediction in the paper is equivalent by construction to an input, and no fitted parameter is renamed as a derived result. The paper is a review with a tutorial, and its claims are traceable to standard theory and external experimental reports; therefore no meaningful circularity is present.

Assumptions & free parameters 0 free parameters · 3 assumptions · 0 invented entities

The review relies on standard microwave theory and the classical Doherty model. The only introduced quantities are design variables (m, k, alpha) that parameterize known designs, not free parameters fitted to data. No new entities are postulated.

assumptions (3)
  • standard math Lossless uniform transmission line equations (telegrapher's equations) for the quarter-wave lines TL1 and TL2
    Used in Section II-A to derive Eq. (3) and Eq. (4) for the carrier impedance Zc(f). Assumes no loss and frequency-independent characteristic impedance.
  • domain assumption Ideal Doherty operation: peaking amplifier is an open circuit at back-off and an ideal current source at peak power; carrier and peaking transistors have identical optimum load Ropt in the symmetric case
    Invoked in Section II-A (and throughout Section III) to compute the k parameter (k=1 at peak, k=0.5 at back-off) and to derive the impedance transformation ratios. Reality includes finite output impedance and parasitic capacitances, acknowledged in Section II-B.
  • standard math Quarter-wave transmission line at center frequency f0 provides exact 90-degree phase shift and impedance inversion
    Used throughout Section II and III to determine characteristic impedances (Eqs. 1-2, 5-7, 9-11) and to analyze bandwidth.

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Cite this review

Pith. "Pith review of Breaking Bandwidth Limit: A Review of Broadband Doherty Power Amplifier Design for 5G." pith.science (2026). https://pith.science/paper/Y6TCLT6V

@misc{pith2026190807755,
  author       = {Pith},
  title        = {Pith review of: Breaking Bandwidth Limit: A Review of Broadband Doherty Power Amplifier Design for 5G},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/Y6TCLT6V}},
  note         = {Machine review of arXiv:1908.07755}
}
read the original abstract

The Doherty power amplifier (DPA) has been extensively explored in the past and has become one of the most widely used power amplifier (PA) architectures in cellular base stations. The classical DPA suffers intrinsic bandwidth constrains which limit its application in future 5G wireless transmitters. In this paper, we present a comprehensive review of the DPA bandwidth enhancement techniques proposed in literature in order to provide a thorough understanding of the DPA's broadband design for high-efficiency 5G wireless transmitters. We elaborate on the main bandwidth limitation sources and provide circuit design insights. We then follow with an overview of bandwidth enhancement techniques developed for the DPA, including modified load-modulation networks, frequency response optimization, parasitic compensation, post-matching, as well as distributed DPA, dual-input digital DPA, transformer-based power-combining PA, and transformer-less load modulated PA architectures. Furthermore, challenges and design techniques for integrated circuit (IC) implementation of broadband DPAs are discussed, including a review of circuits developed in CMOS, SiGe, and GaN processes, and operating in RF and mm-Wave frequencies.

Figures

Figures reproduced from arXiv: 1908.07755 by the authors.

Figure 1
Figure 1. The basic DPA architecture [PITH_FULL_IMAGE:figures/full_fig_p002_1.png] view at source ↗
Figure 2
Figure 2. Real part of the normalized impedance presented to the carrier [PITH_FULL_IMAGE:figures/full_fig_p002_2.png] view at source ↗
Figure 5
Figure 5. Conventional techniques to absorb output parasitic capacitances of [PITH_FULL_IMAGE:figures/full_fig_p003_5.png] view at source ↗
Figures from the paper (23 more)
Figure 4
Figure 4. Figure 4: Real part of the impedance presented to the carrier amplifier at peak [PITH_FULL_IMAGE:figures/full_fig_p003_4.png]
Figure 6
Figure 6. Figure 6: The real part of the impedance presented to the carrier amplifier [PITH_FULL_IMAGE:figures/full_fig_p004_6.png]
Figure 7
Figure 7. Figure 7: Real part of the impedance presented to the carrier amplifier using [PITH_FULL_IMAGE:figures/full_fig_p004_7.png]
Figure 2
Figure 2. Figure 2: Other circuit techniques, including offset lines, resonant [PITH_FULL_IMAGE:figures/full_fig_p004_2.png]
Figure 8
Figure 8. Figure 8: Modified DPA architecture with improved back-off bandwidth [PITH_FULL_IMAGE:figures/full_fig_p005_8.png]
Figure 9
Figure 9. Figure 9: Theoretical drain efficiency of the DPA with maximally flat frequency [PITH_FULL_IMAGE:figures/full_fig_p006_9.png]
Figure 10
Figure 10. Figure 10: The DPA architecture with two-section peaking network for band [PITH_FULL_IMAGE:figures/full_fig_p006_10.png]
Figure 13
Figure 13. Figure 13: The DPA model based on two-port networks for real frequency [PITH_FULL_IMAGE:figures/full_fig_p007_13.png]
Figure 14
Figure 14. Figure 14: Parasitic capacitance cancellation using parallel inductors. [PITH_FULL_IMAGE:figures/full_fig_p007_14.png]
Figure 15
Figure 15. Figure 15: The DPA architecture with parasitic compensation and second-harmonic control [34]. [PITH_FULL_IMAGE:figures/full_fig_p008_15.png]
Figure 16
Figure 16. Figure 16: Parasitic-compensated load modulation network proposed in [36]. [PITH_FULL_IMAGE:figures/full_fig_p008_16.png]
Figure 17
Figure 17. Figure 17: The post-matching DPA proposed in [38]. ing amplifiers are realized by simple low-pass networks in order to extend the bandwidth. Furthermore, a broadband impedance matching network is used at the output of DPA to transform the load resistance into the optimum resista…
Figure 18
Figure 18. Figure 18: The distributed two-way DPA architecture. [PITH_FULL_IMAGE:figures/full_fig_p009_18.png]
Figure 20
Figure 20. Figure 20: The broad bandwidth is achieved by absorbing para [PITH_FULL_IMAGE:figures/full_fig_p009_20.png]
Figure 19
Figure 19. Figure 19: Transmitter architecture with dual-input DPA [10]. [PITH_FULL_IMAGE:figures/full_fig_p010_19.png]
Figure 20
Figure 20. Figure 20: The broadband dual-input DPA circuit using stepped impedance [PITH_FULL_IMAGE:figures/full_fig_p010_20.png]
Figure 22
Figure 22. Figure 22: Broadband transformer-less load modulation PA architecture [52]. [PITH_FULL_IMAGE:figures/full_fig_p010_22.png]
Figure 23
Figure 23. Figure 23: Broadband DPA circuit implemented in a GaAs HBT process [57]. [PITH_FULL_IMAGE:figures/full_fig_p012_23.png]
Figure 24
Figure 24. Figure 24: The impedance inverter network and 0.25- [PITH_FULL_IMAGE:figures/full_fig_p012_24.png]
Figure 25
Figure 25. Figure 25: The 0.25-µm GaN-HEMT MMIC DPA reported in [60]. output and driver amplifier stages, input quadrature hybrid, and varactor-loaded transmission lines to adjust the relative phase shift of the carrier and peaking paths. A power-aware adaptive uneven-feeding scheme is use…
Figure 26
Figure 26. Figure 26: Transformer-based DPA implemented in a 40-nm CMOS process [64]. [PITH_FULL_IMAGE:figures/full_fig_p013_26.png]
Figure 27
Figure 27. Figure 27: The mm-wave multi-band DPA implemented in a 130-nm SiGe [PITH_FULL_IMAGE:figures/full_fig_p013_27.png]
Figure 28
Figure 28. Figure 28: The PA architecture with simultaneous reconfigurable frequency and [PITH_FULL_IMAGE:figures/full_fig_p013_28.png]

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Reference graph

Works this paper leans on

71 extracted references · 71 canonical work pages

  1. [45]

    The (r)evolution of distributed amplifiers: From vacuum tubes to modern CMOS and GaN ICs,

    G. Nikandish, R. B. Staszewski, and A. Zhu, “The (r)evolution of distributed amplifiers: From vacuum tubes to modern CMOS and GaN ICs,” IEEE Microw. Mag., vol. 19, no. 4, pp. 66–83, Jun. 2018

    work page 2018

  2. [55]

    A design procedure for high-efficiency and compact-size 5–10-W MMIC power amplifiers in GaAs pHEMT technology,

    G. Nikandish and A. Medi, “A design procedure for high-efficiency and compact-size 5–10-W MMIC power amplifiers in GaAs pHEMT technology,” IEEE Trans. Microw. Theory Techn. , vol. 61, no. 8, pp. 2922–2933, Aug. 2013

    work page 2013

  3. [56]

    A harmonic termination technique for single- and multi-band high-efficiency class-F MMIC power amplifiers,

    G. Nikandish, E. Babakrpur, and A. Medi, “A harmonic termination technique for single- and multi-band high-efficiency class-F MMIC power amplifiers,” IEEE Trans. Microw. Theory Techn. , vol. 62, no. 5, pp. 1212–1220, May 2014

    work page 2014

  4. [1]

    Millimeter wave mobile communications for 5G cellular: It will work!,

    T. S. Rappaport et al., “Millimeter wave mobile communications for 5G cellular: It will work!,” IEEE Access, vol. 1, pp. 335–349, May 2013

    work page 2013

  5. [2]

    5G white paper,

    “5G white paper,” NGMN Alliance, pp. 1–125, Feb. 2015

    work page 2015

  6. [3]

    Design of energy- and cost-efficient massive MIMO arrays,

    A. Puglielli et al., “Design of energy- and cost-efficient massive MIMO arrays,” Proc. IEEE, vol. 104, no. 3, pp. 586–606, Mar. 2016

    work page 2016

  7. [4]

    A new high efficiency power amplifier for modulated waves,

    W. H. Doherty, “A new high efficiency power amplifier for modulated waves,”Proc. Inst. Radio Eng., vol. 24, no. 9, pp. 1163–1182, Sep. 1936

    work page 1936

  8. [5]

    Will Doherty continue to rule for 5G?,

    P. M. Asbeck, “Will Doherty continue to rule for 5G?,” in Proc. IEEE MTT-S Int. Microwave Symp. Dig. , May 2016, pp. 1–4

    work page 2016

Show all 71 references
  1. [6]

    High-efficiency Doherty power amplifiers: Historical aspect and modern trends,

    B. A. Grebennikov and S. Bulja, “High-efficiency Doherty power amplifiers: Historical aspect and modern trends,” Proc. IEEE, vol. 100, no. 12, pp. 3190–3219, 2012

    2012

  2. [7]

    The Doherty power amplifier,

    B. Kim, K. Jangheon, K. Ildu, and C. Jeonghyeon, “The Doherty power amplifier,” IEEE Microw. Mag., vol. 7, no. 5, pp. 42–50, 2006

    2006

  3. [8]

    Advanced Doherty architecture,

    B. Kim, I. Kim, and J. Moon, “Advanced Doherty architecture,” IEEE Microw. Mag., vol. 11, no. 5, pp. 72–86, Aug. 2010

    2010

  4. [9]

    The Doherty power amplifier: Review of recent solutions and trends,

    V . Camarchia, M. Pirola, R. Quaglia, S. Jee, Y . Cho, and B. Kim, “The Doherty power amplifier: Review of recent solutions and trends,” IEEE Trans. Microw. Theory Techn., vol. 63, no. 2, pp. 559–571, 2015

    2015

  5. [10]

    Doherty goes digital: Digitally enhanced Doherty power amplifiers,

    R. Darraji, P. Mousavi, and F. M. Ghannouchi, “Doherty goes digital: Digitally enhanced Doherty power amplifiers,” IEEE Microw. Mag., vol. 17, no. 8, pp. 41–51, Aug. 2016

    2016

  6. [11]

    Doherty’s legacy: A history of the Doherty power amplifier from 1936 to the present day,

    R. Pengelly, C. Fager, and M. Ozen, “Doherty’s legacy: A history of the Doherty power amplifier from 1936 to the present day,” IEEE Microw. Mag., vol. 17, no. 2, pp. 41–58, Feb. 2016

    1936

  7. [12]

    AM/AM and AM/PM distortion generation mechanisms in Si LDMOS and GaN HEMT based RF power amplifiers,

    L. C. Nunes, P. M. Cabral, and J. C. Pedro, “AM/AM and AM/PM distortion generation mechanisms in Si LDMOS and GaN HEMT based RF power amplifiers,” IEEE Trans. Microw. Theory Techn., vol. 62, no. 4, pp. 799–809, Apr. 2014

    2014

  8. [13]

    Effect of load modulation on phase distortion in Doherty power amplifiers,

    L. Piazzon et al. , “Effect of load modulation on phase distortion in Doherty power amplifiers,” IEEE Microw. Wireless Compon. Lett. , vol. 24, no. 7, pp. 505507, Jul. 2014

    2014

  9. [14]

    Frequency response analysis and bandwidth extension of the Doherty amplifier,

    K. Bathich, A. Z. Markos, and G. Boeck, “Frequency response analysis and bandwidth extension of the Doherty amplifier,” IEEE Trans. Microw. Theory Techn., vol. 59, no. 4, pp. 934–944, Apr. 2011

    2011

  10. [15]

    A modified Doherty configuration for broadband amplification using symmetrical devices,

    D. Y .-T. Wu and S. Boumaiza, “A modified Doherty configuration for broadband amplification using symmetrical devices,” IEEE Trans. Microw. Theory Techn., vol. 60, no. 10, pp. 3201–3213, Oct. 2012

    2012

  11. [16]

    A modified Doherty power amplifier with extended bandwidth and reconfigurable efficiency,

    D. Gustafsson, C. M. Andersson, and C. Fager, “A modified Doherty power amplifier with extended bandwidth and reconfigurable efficiency,” IEEE Trans. Microw. Theory Techn. , vol. 60, no. 1, pp. 533–542, Jan. 2013

    2013

  12. [17]

    Generalized theory and design methodology of wideband Doherty amplifiers applied to the realization of an octave-bandwidth prototype,

    R. Darraji, D. Bhaskar, T. Sharma, M. Helaoui, P. Mousavi, and F. M. Ghannouchi, “Generalized theory and design methodology of wideband Doherty amplifiers applied to the realization of an octave-bandwidth prototype,”IEEE Trans. Microw. Theory Techn., vol. 65, no. 8, pp. 3014– 3...

    2017

  13. [18]

    A dual-band parallel Doherty power amplifier for wireless applications,

    A. Grebennikov and J. Wong, “A dual-band parallel Doherty power amplifier for wireless applications,” IEEE Trans. Microw. Theory Techn., vol. 60, no. 10, pp. 3214–3222, Oct. 2012

    2012

  14. [19]

    A 350 W, 790 to 960 MHz wideband LDMOS Doherty amplifier using a modified combining scheme,

    D. Y .-T. Wu, J. Annes, M. Bokatius, P. Hart, E. Krvavac, and G. Tucker, “A 350 W, 790 to 960 MHz wideband LDMOS Doherty amplifier using a modified combining scheme,” in IEEE MTT-S Int. Microw. Symp. Dig., Jun. 2014, pp. 1–4

    2014

  15. [20]

    A closed-form design technique for ultra-wideband Doherty power amplifiers,

    R. Giofre, L. Piazzon, P. Colantonio, and F. Giannini, “A closed-form design technique for ultra-wideband Doherty power amplifiers,” IEEE Trans. Microw. Theory Techn. , vol. 62, no. 12, pp. 3414–3424, Dec. 2014

    2014

  16. [21]

    A distributed matching/combining network suitable for Doherty power amplifiers covering more than an octave frequency band,

    R. Giofre, L. Piazzon, P. Colantonio, and F. Giannini, “A distributed matching/combining network suitable for Doherty power amplifiers covering more than an octave frequency band,” inMicrowave Symposium (IMS), 2014 IEEE MTT-S International , 2014, pp. 1–3

    2014

  17. [22]

    An ultra- broadband GaN Doherty amplifier with 83% of fractional bandwidth,

    R. Giofre, L. Piazzon, P. Colantonio, and F. Giannini, “An ultra- broadband GaN Doherty amplifier with 83% of fractional bandwidth,” IEEE Microw. Wireless Compon. Lett. , vol. 24, no. 11, pp. 775–777, Nov. 2014

    2014

  18. [23]

    Toward a more generalized Doherty power amplifier design for broadband operation,

    A. Barakat, M. Thian, V . Fusco, S. Bulja, and L. Guan, “Toward a more generalized Doherty power amplifier design for broadband operation,” IEEE Trans. Microw. Theory Techn. , vol. 65, no. 3, pp. 846–859, Mar. 2017

    2017

  19. [24]

    A wideband 700W push-pull Doherty amplifier,

    J. He, J. H. Qureshi, W. Sneijers, D. A. Calvillo-Cortes, and L. C. N. de Vreede, “A wideband 700W push-pull Doherty amplifier,” IEEE MTT-S Int. Microwave Symp. , Phoneix, 2015

    2015

  20. [25]

    A Doherty architecture with high feasibility and defined bandwidth behavior,

    R. Giofre, L. Piazzon, P. Colantonio, and F. Giannini, “A Doherty architecture with high feasibility and defined bandwidth behavior,” IEEE Trans. Microw. Theory Techn., vol. 61, no. 9, pp. 3308–3317, Sep. 2013

    2013

  21. [26]

    A wideband Doherty architecture with 36% of fractional bandwidth,

    L. Piazzon, R. Giofre, P. Colantonio, and F. Giannini, “A wideband Doherty architecture with 36% of fractional bandwidth,” IEEE Microw. Wireless Compon. Lett., vol. 23, no. 11, pp. 626–628, Nov. 2013

    2013

  22. [27]

    A bandwidth enhanced Do- herty power amplifier with a compact output combiner,

    S. Chen, G. Wang, Z. Cheng, and Q. Xue, “A bandwidth enhanced Do- herty power amplifier with a compact output combiner,” IEEE Microw. Wireless Compon. Lett., vol. 26, no. 6, pp. 434–436, Jun. 2016

    2016

  23. [28]

    A broadband three- device Doherty power amplifier based on a modified load modulation network,

    S. Chen, P. Qiao, G. Wang, Z. Cheng, and Q. Xue, “A broadband three- device Doherty power amplifier based on a modified load modulation network,” in Microwave Symposium (IMS), 2016 IEEE MTT-S Interna- tional, 2016, pp. 1–4

    2016

  24. [29]

    An extended bandwidth Doherty amplifier using a novel output combiner,

    M. N. Ali Abadi, H. Golestaneh, H. Sarbishaei, and S. Boumaiza, “An extended bandwidth Doherty amplifier using a novel output combiner,” IEEE MTT-S Int. Microwave Symp. Dig. , 2014, pp. 1–4

    2014

  25. [30]

    Broadband Doherty power amplifier via real frequency technique,

    G. Sun and R. H. Jansen, “Broadband Doherty power amplifier via real frequency technique,” IEEE Trans. Microw. Theory Techn., vol. 60, no. 1, pp. 99–111, Jan. 2012

    2012

  26. [31]

    Wideband harmonically-tuned GaN Doherty power amplifier,

    K. Bathich and G. Boeck, “Wideband harmonically-tuned GaN Doherty power amplifier,” inProc. 2012 IEEE MTT-S Int. Microwave Symp. Dig., Jun. 2012, pp. 1–3

    2012

  27. [32]

    Multiobjective Bayesian optimization for active load modulation in a broadband 20-W GaN Doherty power amplifier design,

    P. Chen, J. Xia, B. M. Merrick, and T. J. Brazil, “Multiobjective Bayesian optimization for active load modulation in a broadband 20-W GaN Doherty power amplifier design,” IEEE Trans. Microw. Theory Techn. , vol. 65, no. 3, pp. 860–871, Mar. 2017

    2017

  28. [33]

    A wideband 20 W LMOS Doherty power amplifier,

    J. H. Qureshi, N. Li, W. C. E. Neo, F. Rijs, I. Blednov, and L. C. N. de Vreede, “A wideband 20 W LMOS Doherty power amplifier,” in IEEE MTT-S Int. Microw. Symp. Dig ., Anaheim, CA, May 2010, pp. 1504–1507

    2010

  29. [34]

    3–3.6-GHz wideband GaN Doherty power amplifier exploiting output compensation stages,

    J. Rubio, J. Fang, V . Camarchia, R. Quaglia, M. Pirola, and G. Ghione, “3–3.6-GHz wideband GaN Doherty power amplifier exploiting output compensation stages,” IEEE Trans. Microw. Theory Techn., vol. 60, no. 8, pp. 2543–2548, Aug. 2012

    2012

  30. [35]

    Design of an 87% fractional bandwidth Doherty power amplifier supported by a simplified bandwidth estimation method,

    J. J. M. Rubio, V . Camarchia, M. Pirola, and R. Quaglia, “Design of an 87% fractional bandwidth Doherty power amplifier supported by a simplified bandwidth estimation method,” IEEE Trans. Microw. Theory Techn., vol. 66, no. 3, pp. 1319–1327, Mar. 2018

    2018

  31. [36]

    Frequency analysis and multiline implementation of compensated impedance in- verter for wideband Doherty high-power amplifier design,

    A. Cidronali, S. Maddio, N. Giovannelli, and G. Collodi, “Frequency analysis and multiline implementation of compensated impedance in- verter for wideband Doherty high-power amplifier design,” IEEE Trans. Microw. Theory Techn., vol. 64, no. 5, pp. 1359–1372, May 2016

    2016

  32. [37]

    A broadband high-efficiency Doherty power amplifier with integrated compensating reactance,

    J. Xia, M. Yang, Y . Guo, and A. Zhu, “A broadband high-efficiency Doherty power amplifier with integrated compensating reactance,” IEEE Trans. Microw. Theory Techn., vol. 64, no. 7, pp. 2014–2024, Jul. 2016

    2014

  33. [38]

    A post-matching Doherty power amplifier employing low-order impedance inverters for broadband applications,

    J. Pang, S. He, C. Huang, Z. Dai, J. Peng, and F. You, “A post-matching Doherty power amplifier employing low-order impedance inverters for broadband applications,” IEEE Trans. Microw. Theory Techn. , vol. 63, no. 12, pp. 4061–4071, Dec. 2015

    2015

  34. [39]

    Broadband efficiency-enhanced mutually coupled harmonic postmatching Doherty power amplifier,

    X. Y . Zhou, S. Y . Zheng, W. S. Chan, S. Chen, and D. Ho, “Broadband efficiency-enhanced mutually coupled harmonic postmatching Doherty power amplifier,” IEEE Trans. Circuits Syst. I, Reg. Papers , pp. 1–14,

  35. [40]

    Octave bandwidth Doherty power amplifier using multiple resonance circuit for the peaking amplifier,

    H. Kang et al. , “Octave bandwidth Doherty power amplifier using multiple resonance circuit for the peaking amplifier,” IEEE Trans. on Circuits and Systems I: Reg. Papers. DOI: 10.1109/TCSI.2018.2869905

    2018

  36. [41]

    On the continuity of high efficiency modes in linear RF power amplifiers,

    S. C. Cripps, P. J. Tasker, A. L. Clarke, J. Lees, and J. Benedikt, “On the continuity of high efficiency modes in linear RF power amplifiers,” IEEE Microw. Wireless Compon. Lett. , vol. 19, no. 10, pp. 665–667, Oct. 2009

    2009

  37. [42]

    A broadband Doherty power amplifier based on continuous-mode technology,

    X. Chen, W. Chen, F. M. Ghannouchi, Z. Feng, and Y . Liu, “A broadband Doherty power amplifier based on continuous-mode technology,” IEEE 15 Trans. Microw. Theory Techn. , vol. 64, no. 12, pp. 4505–4517, Dec. 2016

    2016

  38. [43]

    A 200W broadband continuous-mode Doherty power amplifier for base- station applications,

    X. Chen, W. Chen, Q. Zhang, F. M. Ghannouchi, and Z. Feng, “A 200W broadband continuous-mode Doherty power amplifier for base- station applications,” IEEE MTT-S Int. Microwave Symp. Dig., 2017, pp. 1110–1113

    2017

  39. [44]

    Broadband continuous-mode Doherty power amplifiers with noninfinity peaking impedance,

    W. Shi et al., “Broadband continuous-mode Doherty power amplifiers with noninfinity peaking impedance,” IEEE Trans. Microw. Theory Techn., vol. 66, no. 2, pp. 1034–1046, Feb. 2018

    2018

  40. [46]

    A new wideband distributed Doherty amplifier for WCDMA repeater applications,

    Y . Lee, M. Lee, S. Kam, and Y . Jeong, “A new wideband distributed Doherty amplifier for WCDMA repeater applications,” IEEE Microw. Wireless Compon. Lett., vol. 19, no. 10, pp. 668–670, Oct. 2009

    2009

  41. [47]

    Adaptive input-power distribution in Doherty power amplifiers for linearity and efficiency enhancement,

    M. Nick and A. Mortazawi, “Adaptive input-power distribution in Doherty power amplifiers for linearity and efficiency enhancement,” IEEE Trans. Microw. Theory Techn. , vol. 58, no. 11, pp. 2764–2771, Nov. 2010

    2010

  42. [48]

    Mitigation of bandwidth limitation in wireless Doherty amplifiers with substantial bandwidth enhancement using digital techniques,

    R. Darraji, F. M. Ghannouchi, and M. Helaoui, “Mitigation of bandwidth limitation in wireless Doherty amplifiers with substantial bandwidth enhancement using digital techniques,” IEEE Trans. Microw. Theory Techn., vol. 60, no. 9, pp. 2875–2885, Sept. 2012

    2012

  43. [49]

    A 1–3-GHz digitally controlled dual-RF input power-amplifier design based on a Doherty-Outphasing continuum analysis,

    C. M. Andersson, D. Gustafsson, J. Chani Cahuana, R. Hellberg, and C. Fager, “A 1–3-GHz digitally controlled dual-RF input power-amplifier design based on a Doherty-Outphasing continuum analysis,”IEEE Trans. Microw. Theory Techn., vol. 61, no. 10, pp. 3743–3752, Oct. 2013

    2013

  44. [50]

    Digitally equalized Doherty RF front-end architecture for broadband and multi- standard wireless transmitters,

    R. Darraji, A. K. Kwan, F. M. Ghannouchi, and M. Helaoui, “Digitally equalized Doherty RF front-end architecture for broadband and multi- standard wireless transmitters,” IEEE Trans. Microw. Theory Techn., vol. 63, no. 6, pp. 1978–1988, Jun. 2015

    1978

  45. [51]

    Fully integrated CMOS power amplifier with efficiency enhancement at power back-off,

    G. Liu, P. Haldi, T.-J. K. Liu, and A. M. Niknejad, “Fully integrated CMOS power amplifier with efficiency enhancement at power back-off,” IEEE J. Solid-State Circuits , vol. 43, no. 3, pp. 600–609, Mar. 2008

    2008

  46. [52]

    Transformer-less load- modulated (TLLM) architecture for efficient wideband power ampli- fiers,

    M. Akbarpour, M. Helaoui, and F. Ghanouchi, “Transformer-less load- modulated (TLLM) architecture for efficient wideband power ampli- fiers,” IEEE Trans. Microw. Theory Techn. , vol. 60, no. 9, pp. 2863– 2874, Sept. 2012

    2012

  47. [53]

    Design of GaN Doherty power amplifiers for broadband applications,

    J. Shao et al., “Design of GaN Doherty power amplifiers for broadband applications,” IEEE Microw. Wireless Compon. Lett., vol. 24, no. 4, pp. 248–250, Apr. 2014

    2014

  48. [54]

    A miniature broadband Doherty power amplifier with a series-connected load,

    S. Watanabe, Y . Takayama, R. Ishikawa, and K. Honjo, “A miniature broadband Doherty power amplifier with a series-connected load,” IEEE Trans. Microw. Theory Techn., vol. 63, no. 2, pp. 572–579, Feb. 2015

    2015

  49. [57]

    Design of bandwidth-enhanced Doherty power amplifiers for handset applications,

    D. Kang, D. Kim, Y . Cho, B. Park, J. Kim, and B. Kim, “Design of bandwidth-enhanced Doherty power amplifiers for handset applications,” IEEE Trans. Microw. Theory Techn. , vol. 59, no. 12, pp. 3474–3483, Dec. 2011

    2011

  50. [58]

    Asymmetric broadband Doherty power amplifier using GaN MMIC for femto-cell base-station,

    S. Jee et al. , “Asymmetric broadband Doherty power amplifier using GaN MMIC for femto-cell base-station,” IEEE Trans. Microw. Theory Techn., vol. 63, no. 9, pp. 2802–2810, Sep. 2015

    2015

  51. [59]

    A wideband and compact GaN MMIC Doherty amplifier for microwave link applications,

    D. Gustafsson, J. C. Cahuana, D. Kuylenstierna, I. Angelov, N. Rorsman, and C. Fager, “A wideband and compact GaN MMIC Doherty amplifier for microwave link applications,” IEEE Trans. Microw. Theory Techn. , vol. 61, no. 2, pp. 922–930, Feb. 2013

    2013

  52. [60]

    A GaN MMIC modified Doherty PA with large bandwidth and reconfigurable efficiency,

    D. Gustafsson, J. C. Cahuana, D. Kuylenstierna, I. Angelov, and C. Fager, “A GaN MMIC modified Doherty PA with large bandwidth and reconfigurable efficiency,” IEEE Trans. Microw. Theory Techn., vol. 62, no. 12, pp. 3006–3016, Dec. 2014

    2014

  53. [61]

    A highly efficient and linear power amplifier for 28-GHz 5G phased array radios in 28-nm CMOS,

    S. Shakib, H.-C. Park, J. Dunworth, V . Aparin, and K. Entesari, “A highly efficient and linear power amplifier for 28-GHz 5G phased array radios in 28-nm CMOS,” IEEE J. Solid-State Circuits , vol. 51, no. 12, pp. 3020–3036, Dec. 2016

    2016

  54. [62]

    A wideband class-AB power amplifier with 29–57-GHz AM-PM compensation in 0.9-V 28-nm bulk CMOS,

    M. Vigilante and P. Reynaert, “A wideband class-AB power amplifier with 29–57-GHz AM-PM compensation in 0.9-V 28-nm bulk CMOS,” IEEE J. Solid-State Circuits , vol. 53, no. 5, pp. 1288–1301, May 2018

    2018

  55. [63]

    Active millimeter-wave phase-shift Doherty power amplifier in 45-nm SOI CMOS,

    A. Agah, H. T. Dabag, B. Hanafi, P. M. Asbeck, J. F. Buckwalter and L. E. Larson, “Active millimeter-wave phase-shift Doherty power amplifier in 45-nm SOI CMOS,” IEEE J. Solid-State Circuits, vol. 48, no. 10, pp. 2338–2350, Oct. 2013

    2013

  56. [64]

    Transformer-based Doherty power amplifiers for mm-Wave applications in 40-nm CMOS,

    E. Kaymaksut, D. Zhao, and P. Reynaert, “Transformer-based Doherty power amplifiers for mm-Wave applications in 40-nm CMOS,” IEEE Trans. Microw. Theory Techn., vol. 63, no. 4, pp. 1186–1192, Apr. 2015

    2015

  57. [65]

    A 28GHz/37GHz/39GHz multiband linear Doherty power amplifier for 5G massive MIMO applications,

    S. Hu, F. Wang, and H. Wang, “A 28GHz/37GHz/39GHz multiband linear Doherty power amplifier for 5G massive MIMO applications,” in IEEE Int. Solid-State Circuits Conf. (ISSCC) Dig. Tech. Papers , Feb. 2017, pp. 32–33

    2017

  58. [66]

    A 38–46 GHz MMIC Doherty power amplifier using post-distortion linearization,

    J. H. Tsai and T. W. Huang, “A 38–46 GHz MMIC Doherty power amplifier using post-distortion linearization,” IEEE Microw. Wireless Compon. Lett., vol. 17, no. 5, pp. 388–390, May 2007

    2007

  59. [67]

    Efficient millimeter wave Doherty PA design based on a low-loss combiner synthesis technique,

    M. Ozen, N. Rostomyan, K. Aufinger, and C. Fager, “Efficient millimeter wave Doherty PA design based on a low-loss combiner synthesis technique,” IEEE Microw. Wireless Compon. Lett. , vol. 27, no. 12, pp. 1143–1145, Dec. 2017

    2017

  60. [68]

    28 GHz Doherty power amplifier in CMOS SOI with 28% back-off PAE,

    N. Rostomyan, M. Ozen and P. Asbeck, “28 GHz Doherty power amplifier in CMOS SOI with 28% back-off PAE,” IEEE Microw. Wireless Compon. Lett., vol. 28, no. 5, pp. 446–448, May 2018

    2018

  61. [69]

    A 32 GHz 20 dBm-P SAT transformer- based Doherty power amplifier for multi-Gb/s 5G applications in 28 nm bulk CMOS,

    P. Indirayanti and P. Reynaert, “A 32 GHz 20 dBm-P SAT transformer- based Doherty power amplifier for multi-Gb/s 5G applications in 28 nm bulk CMOS,” in IEEE RFIC Symp. Dig. Papers , Jun. 2017, pp. 45–48

    2017

  62. [70]

    Simultaneously broadband and back-off efficient mm-wave PAs: A multi-port network synthesis approach,

    C. R. Chappidi, X. Wu and K. Sengupta, “Simultaneously broadband and back-off efficient mm-wave PAs: A multi-port network synthesis approach,” IEEE J. Solid-State Circuits , vol. 53, no. 9, pp. 2543–2559, Sept. 2018

    2018

  63. [2017]

    vol. 64, no. 7, pp. 1758–1771, Jul. 2017

    2017

Pith tools

Reviewed August 14, 2026 · model on record in the stance chip above.