Model-Based Nonlinear Embedding for Power-Amplifier Design

Abstract

In 1996, he joined a nonprofit governmental organization, Small Business Corporation, Shiheung, Korea. He was a Product Development Assistant Consultant until 2007, and had been involved in over 100

Extended theoretical analysis method on the performance of high-efficiency power amplifiers by solving nonlinear waveform determination process

“…Harmonic‐tuned amplifiers such as class‐F and class‐J power amplifiers (PAs) and switch‐mode amplifiers such as class‐E PAs constitute the main categories of high‐efficiency PAs . With properly designed harmonic load impedances, they can offer high‐efficiency performance owing to reduced transistor loss …”

“…Harmonic-tuned amplifiers such as class-F 1,2 and class-J 3,4 power amplifiers (PAs) and switch-mode amplifiers such as class-E PAs 5-8 constitute the main categories of highefficiency PAs. 9 With properly designed harmonic load impedances, 2,10 they can offer high-efficiency performance owing to reduced transistor loss. 11 To provide high-efficiency performance, transistors must be driven into saturation or switch states 12 to get the correct ratios between fundamental and harmonic voltage components.…”

Waveform engineering: State-of-the-art and future trends (invited paper)

“…An interesting variant was recently proposed by Roblin: the model-based nonlinear embedding. [45][46][47] Starting from Figure 1, the idea is to directly apply the optimum impedance conditions suggested by the theory 14-21 at the CGP. To accomplish this, the device model is separated into its three different parts, i.e., a resistive core, a capacitive core, and a linear parasitic network.…”

Exploring the impedance coverage limitation at current generate plane of transistors up to millimeter‐wave band based on comprehensive large signal model

“…8 Roblin et al introduced an intrinsic method from the CG plane and embedded the nonlinear and linear parasitic components, to predict the harmonic load at the transistor package (TP) plane, based on nonlinear models. 12 Similarly, waveform engineering conception was also summarized by Tasker as "the ability to modify the time-varying voltage and current present in quantified manner. 9 " The waveform design method and RF I/V waveform…”

“…In order to compensate the harmonic power losses due to the parasitic network, an extra active harmonic injection with constructive and destructive phases is introduced, and thus the reflection coefficient at the CG plane can achieve the whole unity circle of the Smith chart. 12 The harmonic injection method to improve the efficiency is an improvement for the PA theory. However, it requires an extra modified harmonic source and is hard to be realized in practice, and the reduced and rotated impedance coverage at the CG plane and its influence on harmonic tuning have not been studied comprehensively.…”