1MA279: Doherty, Balanced, Push-Pull & Spatial Amplifier Performance Enhancement

The Doherty Amplifier continues to be rolled out in an increasing number of TxFE (Transmit Frontend) applications, as the quasi-linear amplifier architecture of choice.

The advent of 5G, with its inevitable microwave or millimeter wave air interface, increase the design challenges associated with its construction; not least of all because of the potential for increased dispersion in the constituent amplifiers and combiners.

This application note describes a measurement-based development methodology by which the Doherty Amplifier may be enhanced, increasing performance and/or performance bandwidth. This methodology is supported with a working example.

The methodology may also be extended to balanced, spatially combined and anti-phase (so called "pushpull" or "differential") amplifiers, the latter often itself nested in Doherty configurations.

The R&S®Quickstep sequencing software may be downloaded from:



(1) DohBalSpatAmpPerfEnh.pdf

The application note, complete with instructions.

(2) CST_Macros_RS.zip

A macro for use with Studio Suite, enabling automatic creation of Rat-Race + Schiffman networks from user defined parameters.

(3) CST_solution1_models.zip

A Studio Suite solution with Wilkinson splitter + High-pass + Low-pass filter, illustrating solution 1of the Application Note.

(4) CST_solution5_wilkinson.zip

A Studio Suite solution with Wilkinson splitter + High-pass + Low-pass filter, illustrating solution 5 of the Application Note.

(5) 3GPP_Type_License_Free_Signal_Library.zip

A library of license free signals, for use with the SMW200A signal generator, similar to those used in the Application Note to (i) calibrate and (ii) characterize the DUT.

(6) 20160929_DohertyCharacterization.zip

The Quickstep project used for calibration and rapid characterization of the DUT. Instructions for the installation of the Quickstep project are given in a readme within the archive.

Name Type Language Version Date Size
1MA279_2e_DohBalSpatAmpPerfEnh.pdf Application Note English 2e 15.11.2017 4 MB
CST_Macros_RS.zip Application Note File English 26.09.2016 22 kB
CST_solution1_models.zip Application Note File English 26.09.2016 3 MB
CST_solution5_wilkinson.zip Application Note File English 26.09.2016 181 kB
3GPP_Type_License_Free_Signal_Library.zip Application Note File English 2.0 26.09.2016 2 MB
20160929_DohertyCharacterization.zip Application Note File English 31.10.2016 7 MB
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