Multitone power and intermodulation load-pull characterization of microwave transistors suitable for linear SSPA's design

Hajji, R.; Beanregard, F.; Ghannouchi, Fadhel M.

doi:10.1109/22.598446

Cited by 42 publications

(9 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…An example of load-pull contours demonstrated in the literature for a similar linearity metric (intermodulation rejection) is shown by Hajji et al [35]. Because a constraint is placed on the PAE in the optimization, and the PAE optimum is normally close to the ACPR optimum, this will tend to force the optimization toward the global ACPR optimum.…”

Section: Introductionmentioning

confidence: 89%

Optimization of power-amplifier load impedance and waveform bandwidth for real-time reconfigurable radar

Fellows

Flachsbart

Barlow

et al. 2015

IEEE Trans. Aerosp. Electron. Syst.

View full text Add to dashboard Cite

To create a reconfigurable radar transmitter, the power amplifier circuitry and waveform must be able to adjust in real time to changing operating frequencies and spectral requirements. For range radars, better range resolution can be accomplished by using waveforms of higher bandwidth. In this case it is desirable to maximize the chirp waveform bandwidth while maintaining spectral compliance and meeting power-added efficiency requirements. Based on the concept of the Smith Tube (presented in a recent conference article), this article describes a new intelligent, vector-based search for the load impedance and waveform bandwidth. The search provides the largest possible bandwidth while maintaining the power-added efficiency and adjacent-channel power ratio within specified requirements. The algorithm is demonstrated in measurement with multiple starting impedances and bandwidth search ranges, and consistently accurate and useful results are obtained. Multiple iterations of the two-part search can be performed for increased precision if the time needed to take additional measurements can be tolerated.

show abstract

Section: Introductionmentioning

confidence: 89%

Optimization of power-amplifier load impedance and waveform bandwidth for real-time reconfigurable radar

Fellows

Flachsbart

Barlow

et al. 2015

IEEE Trans. Aerosp. Electron. Syst.

View full text Add to dashboard Cite

show abstract

“…On the other hand, a simple active load-pull system, consisting of an additional synthesiser to generate an ¾ voltage wave towards the drain of the device, only can realise a certain load at either ½ or ¾ , while the load presented at the other frequency and also at the higher harmonic and intermodulation frequencies will be approximately 50 ª. This configuration is not suited to optimise the intermodulation level performance as function of load impedances [5], but can be used for model verification purposes. The variation of only one fundamental load impedance is mostly sufficient to reveal potential modelling limitations.…”

Section: Description Of the Measurement Configurationmentioning

confidence: 94%

Verification of Non-Linear MOSFET Models by Intermodulation Measurements Under Loadpull Conditions

Schreurs

Vandamme

Vandenberghe

et al. 2000

55th ARFTG Conference Digest

View full text Add to dashboard Cite

The trend towards system-on-chip realisation tightens the design specifications and consequently imposes high accuracy requirements on device models. Hence, model validations by only singletone CW excitations do no longer suffice, because the obtained accuracy can not straightforwardly be extrapolated to an expected accuracy under realistic large-signal operating conditions. We developed a measurement set-up that enables to characterise the amplitude and phase of intermodulation products at different load impedances, which can serve as an important verification tool with regard to power amplifier applications. This technique is applied to evaluate two non-linear MOSFET model representations: the compact BSIM3v3 model and the in-house developed look-up table model. We show that for both model types the phase disagreement is more pronounced than the amplitude inaccuracy. We also stress the importance of an adequate de-embedding of the bonding pads and access transmission lines.

show abstract

“…Fu demonstrates a varactor-based tunable matching network to improve both efficiency and linearity [4]. Hajji analyzes the necessary change in input power for constant intermodulation rejection [5]. The Power Smith Tube is a unique extension of the Smith Chart to incorporate input power into the design.…”

Section: Introductionmentioning

confidence: 99%

The Power Smith Tube: Joint optimization of power amplifier input power and load impedance for power-added efficiency and adjacent-channel power ratio

Barkate

Fellows

Barlow

et al. 2015

2015 IEEE 16th Annual Wireless and Microwave Technology Conference (WAMICON)

View full text Add to dashboard Cite

A new visualization tool for design is introduced: the Power Smith Tube. It provides aid in designing for optimum power-added efficiency (P AE) while meeting adjacent-channel power ratio (A CPR) requirements. The Power Smith Tube is a three-dimensional cylindrical extension of the Smith Chart with input power as the vertical axis. As such, this Smith Tube allows the visualization of design metrics, such as P AE and ACPR, as a function of both input power and load impedance. Performance of load-pull measurements or simulations at multiple values of input power provides data for the design. Design examples using the Power Smith Tube based on both simulation and measurement data are presented to demonstrate selection of load impedance and input power providing the highest P AE under ACPR constraints.

show abstract

Multitone power and intermodulation load-pull characterization of microwave transistors suitable for linear SSPA's design

Cited by 42 publications

References 4 publications

Optimization of power-amplifier load impedance and waveform bandwidth for real-time reconfigurable radar

Optimization of power-amplifier load impedance and waveform bandwidth for real-time reconfigurable radar

Verification of Non-Linear MOSFET Models by Intermodulation Measurements Under Loadpull Conditions

The Power Smith Tube: Joint optimization of power amplifier input power and load impedance for power-added efficiency and adjacent-channel power ratio

Contact Info

Product

Resources

About