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Wireless Energy Transmission High-Efficiency DC-AC Converter Using High-Gain High-Efficiency Two-Stage Class-E Power Amplifier

  • Choi, Jae-Won;Seo, Chul-Hun
    • Journal of electromagnetic engineering and science
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    • v.11 no.3
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    • pp.161-165
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    • 2011
  • In this paper, a high-efficiency DC-AC converter is used for wireless energy transmission. The DC-AC convertter is implemented by combining the oscillator and power amplifier. Given that the conversion efficiency of a DC-AC converter is strongly affected by the efficiency of the power amplifier, a high-efficiency power amplifier is implemented using a class-E amplifier structure. Also, because of the low output power of the oscillator connected to the input stage of the power amplifier, a high-gain two-stage power amplifier using a drive amplifier is used to realize a high-output power DC-AC converter. The high-efficiency DC-AC converter is realized by connecting the oscillator to the input stage of the high-gain high-efficiency two-stage class-E power amplifier. The output power and the conversion efficiency of the DC-AC converter are 40.83 dBm and 87.32 %, respectively, at an operation frequency of 13.56 MHz.

The Design of Ultra-broadband Power Amplifier using a Negative Feedback (부궤환을 이용한 광대역 전력증폭기 설계)

  • Lee, Han-Young;Kim, Dae-Jung
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.58 no.8
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    • pp.1572-1579
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    • 2009
  • In this dissertation ultra-broadband power amplifier(UPA) was designed and fabricated using negative feedback technique. UPA was made of pre-amplifier, drive amplifier and power amplifier. Negative feedback technique was used to achieve ultra-broadband performance. Designed power amplifier has 30dB gain and 2W output power. The load-pull data of power amplifier for optimal power matching was extracted from the measured S-parameter. Fabricated PCB material, permittivity is 4.6 and thickness is 0.8mm, is FR4 and UPA was fabricated 3 modules for comparison of the simulated and measured results. Size of the fabricated pre-amplifier and drive amplifier module is 40mm'50mm'16mm. And from the experimental results, gain of the pre-amplifier module is 9.87dB at 2GHz and flatness is 0.63dB. Experimental result of the drive amplifier module is 10.97dB at 2GHz and flatness of that is 0.26dB. Test result of the power amplifier module is 10.71dB at 2GHz and flatness is 0.72dB. Total size of the power amplifier is 45mm'134mm'16mm. According to the test results, gain of the UPA is 28.98dB at 2GHz and flatness is 1.68dB. Output power was 32.098dBm at 2GHz, 32.154dBm at 1GHz and 31.273dBm at 100MHz.

Design of High Efficiency Power Amplifier Using Adaptive Bias Technique and DGS (적응형 바이어스기법과 DGS를 이용한 고효율 전력증폭기설계)

  • Oh, Chung-Gyun;Son, Sung-Chan
    • 한국정보통신설비학회:학술대회논문집
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    • pp.403-408
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    • 2008
  • In this paper, the high efficiency and linearity Doherty power amplifier using DGS and adaptive bias technique has been designed and realized for 2.3GHz WiBro applications. The Doherty amplifier has been implemented us-ing silicon MRF 281 LDMOS FET. The RF performances of the Doherty power amplifier (a combination of a class AB carrier amplifier and a bias-tuned class C peaking amplifier) have been compared with those of a class AB amplifier alone, and conventional Doherty amplifier. The Maximum PAE of designed Doherty power amplifier with DGS and adaptive bias technique has been 36.6% at 34.01dBm output power. The proposed Doherty power amplifier showed an improvement 1dB at output power and 7.6% PAE than a class AB amplifier alone.

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A Study on Efficiency Extension of a High Power Doherty Amplifier Using Unequal LDMOS FET's (불 균등한 LDMOS FET를 이용한 고 출력 도허티 증폭기의 효율 확장에 관한 연구)

  • Hwang, In-Hong;Kim, Jong-Heon
    • Proceedings of the Korea Electromagnetic Engineering Society Conference
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    • pp.81-86
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    • 2005
  • In this paper, we present an efficiency extension of Doherty power amplifier using LDMOS FET devices with different peak output powers and an unequal power divider. The amplifier is designed by using a MRF21045 with P1 dB of 45 W as the main amplifier biased for Class-AB operation and a MRF21090 with P1 dB of 90 W as the peaking amplifier biased for Class-C operation. The input power is divided into a 1:1.5 power ratio between the main and peaking amplifier. The simulated results of the proposed Doherty amplifier shows an efficiency improvement of approximately 19 % in comparison to the class-AB amplifier at an output power of 42.5 dBm. The fabricated Doherty amplifier obtained a PAE of 33.68 % at 9 dB backed off from P1 dB of 51.5 dBm.

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1.9-GHz CMOS Power Amplifier using Adaptive Biasing Technique at AC Ground

  • Kang, Inseong;Yoo, Jinho;Park, Changkun
    • Journal of information and communication convergence engineering
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    • v.17 no.4
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    • pp.285-289
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    • 2019
  • A 1.9-GHz linear CMOS power amplifier is presented. An adaptive bias circuit (ABC) that utilizes an AC ground to detect the power level of the input signal is proposed to enhance the linearity and efficiency of the power amplifier. The ABC utilizes the second harmonic component as the input to mitigate the distortion of the fundamental signal. The input power level of the ABC was detected at the AC ground located at the VDD node of the power amplifier. The output of the ABC was fed into the inputs of the power stage. The input signal distortion was mitigated by detecting the input power level at the AC ground. The power amplifier was designed using a 180 nm RFCMOS process to evaluate the feasibility of the application of the proposed ABC in the power amplifier. The measured output power and power-added efficiency were improved by 1.7 dB and 2.9%, respectively.

6-GHz-to-18-GHz AlGaN/GaN Cascaded Nonuniform Distributed Power Amplifier MMIC Using Load Modulation of Increased Series Gate Capacitance

  • Shin, Dong-Hwan;Yom, In-Bok;Kim, Dong-Wook
    • ETRI Journal
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    • v.39 no.5
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    • pp.737-745
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    • 2017
  • A 6-GHz-to-18-GHz monolithic nonuniform distributed power amplifier has been designed using the load modulation of increased series gate capacitance. This amplifier was implemented using a $0.25-{\mu}m$ AlGaN/GaN HEMT process on a SiC substrate. With the proposed load modulation, we enhanced the amplifier's simulated performance by 4.8 dB in output power, and by 13.1% in power-added efficiency (PAE) at the upper limit of the bandwidth, compared with an amplifier with uniform gate coupling capacitors. Under the pulse-mode condition of a $100-{\mu}s$ pulse period and a 10% duty cycle, the fabricated power amplifier showed a saturated output power of 39.5 dBm (9 W) to 40.4 dBm (11 W) with an associated PAE of 17% to 22%, and input/output return losses of more than 10 dB within 6 GHz to 18 GHz.

Reliability Evaluation of RF Power Amplifier for Wireless Transmitter

  • Choi, Jin-Ho
    • Journal of information and communication convergence engineering
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    • v.6 no.2
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    • pp.154-157
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    • 2008
  • A class-E RF(Radio Frequency) power amplifier for wireless application is designed using standard CMOS technology. To drive the class-E power amplifier, a class-F RF power amplifier is used and the reliability characteristics are studied with a class-E load network. The reliability characteristic is improved when a finite-DC feed inductor is used instead of an RF choke with the load. After one year of operating, when the load is an RF choke the output current and voltage of the power amplifier decrease about 17% compared to initial values. But when the load is a finite DC-feed inductor the output current and voltage decrease 9.7%. The S-parameter such as input reflection coefficient(S11) and the forward transmission scattering parameter(S21) is simulated with the stress time. In a finite DC-feed inductor the characteristics of S-parameter are changed slightly compared to an RF-choke inductor. From the simulation results, the class-E power amplifier with a finite DC-feed inductor shows superior reliability characteristics compared to power amplifier using an RF choke.

New High-efficiency Power Amplifier System for High-directional Piezoelectric Transducer (고지향성 압전 트랜스듀서용 새로운 고효율 전력 증폭기)

  • Kim, Jin-Young;Kim, In-Dong;Moon, Wonkyu
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.67 no.3
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    • pp.383-390
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    • 2018
  • Piezoelectric micro-machined ultrasonic transducers for highly directional speaker need DC bias voltage. Most existing power amplifiers are not suitable for use in highly directional transducers because they are based on AC. In addition, since the piezoelectric micro-machined ultrasonic transducer has a large capacitive reactance, the power efficiency of the power amplifier is very low. Thus this paper proposes a new high efficiency power amplifier with DC bias voltage. In addition, by designing a matching circuit to compensate the capacitive reactance of the micro-machined ultrasonic transducer, the power efficiency of the power amplifier increases. The operating characteristics of the proposed power amplifier was verified by an experimental prototype. The proposed power amplifier is expected to be widely used in designing and implementing other related power amplifiers.

Design of High-efficiency Power Amplifier System for High-directional Speaker (고지향성 스피커를 위한 새로운 전력 증폭기 설계)

  • Kim, Jin-Young;Kim, In-Dong;Moon, Wonkyu
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.66 no.8
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    • pp.1215-1221
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    • 2017
  • Parametric array transducers are used for highly directional speaker in an air environments. Piezoelectric micromachined ultrasonic transducers for parametric array transducers need DC-biased voltage driving signals in order to get high-directional quality-sound features. The existing power amplifier such as class A amplifiers has low efficiency and require large volume heatsinks. To overcome the above-mentioned disadvantages of the conventional amplifier, this paper proposes a new power amplifier system. The proposed power amplifier system ensures high linearity of output characteristic by utilizing the push-pull class B type amplifier. Furthermore, the proposed power amplifier system gets high efficiency because it contains the DC-DC converter-type power supply which can perform energy recovery and envelope tracking function. Also the paper suggests the detailed circuit topology. Its characteristics are verified by the detailed experimental results.

Design of an High Efficiency Pallet Power Amplifier Module (S-대역 고효율 Pallet 전력증폭기 모듈 설계)

  • Choi, Gil-Wong;Kim, Hyoung-Jong;Choi, Jin-Joo;Choi, Jun-Ho
    • Journal of the Korea Institute of Military Science and Technology
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    • v.13 no.6
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    • pp.1071-1079
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    • 2010
  • This paper describes the design and fabrication of a high-efficiency GaN HEMT(Gallium Nitride High-electron Mobility Transistor) Pallet power amplifier module for S-band phased array radar applications. Pallet amplifier module has a series 2-cascaded power amplifier and the final amplification-stage consists of balanced GaN HEMT transistor. In order to achieve high efficiency characteristic of pallet power amplifier module, all amplifiers are designed to the switching-mode amplifier. We performed with various PRF(Pulse Repetition Frequency) of 1, 10, 100 and 1000Hz at a fixed pulse width of $100{\mu}s$. In the experimental results, the output power, gain, and drain efficiency(${\eta}_{total}$) of the Pallet power amplifier module are 300W, 33dB, and 51% at saturated output power of 2.9GHz, respectively.