A novel high-efficiency Doherty amplifier is presented. A carrier amplifier and a peak amplifier in the Doherty amplifier are set to asymmetrical drain voltages to extend the power range where a high drain efficiency of the Doherty amplifier is maintained. Matching circuits of the carrier amplifier and the peak amplifier are designed for each drain voltage so that the drain efficiency and signal linearity of the Doherty amplifier at a 9 dB backoff point from its saturated output power (Psat) become higher than those of a conventional Doherty amplifier. These simple steps optimize the power range of the Doherty amplifier for a wideband code-division multipleaccess (W-CDMA) signal that has a peak-to-average power ratio (PAR) of 9 dB. A Doherty amplifier containing gallium nitride (GaN) high-electron-mobility transistors (HEMTs) achieves an adjacent channel leakage power ratio (ACLR) of -38 dBc and a drain efficiency of 50% at an output power of 45 dBm. This is the highest drain efficiency of a Doherty amplifier for a W-CDMA signal to the best of the authors' knowledge.Index Terms -Doherty amplifier, gallium nitride highelectron-mobility transistor (GaN HEMT), adjacent channel leakage power ratio (ACLR), drain efficiency, wideband codedivision multiple-access (W-CDMA)
Abshclef -Small size radlo frequency (RQ multi chip module for dual band (ZAG& and SG€Iz) wireless local area network ( % " I arulications is described. The full 11. DESIGN OF THE RF MODULE -.. funclIona between base band inpuWontpnt WO) and RIi mteuna switch are integrated in tbe RF modde. In order to reduce size Of the RR module, embedded 5GRz band pass fdter 0, build-up multi-layer o q m i c substrate and lip RF module in this paper the between base band U0 and RF a " switch for dual band WLAN systems. The block diagram iS shown in c h i technology are used. &of them module is 24mm 32mm I 2. 1", hClUdhg shield COVW and EOnUeEtOFJ. This is the mioimum size in modules with same functions for dual band WLAN as far as the authors know. And e l e c h i d performances of the RF module ue evaluated using WAN denals. This reuort rresents desien and exrelimental nosults figure I. It is found that the architecture of W c e i v e r is Two 1es, 1c1 and IC2, are used in the RF module' IC' is the and demodulatcJr of base band in-phdq-me VQ) signals and intermediate kcluency (IF) Sigds. IC1 also ofsmaU alze RF.modole for dual band e applications. chip modules, wireless LAN. Indcx Term -band pars lilters, Bip chip devices. multi I. INTRODUCTTON5GHz W A N systems [l] arc increasing in the wireless communication market because they have such advantages of higb data transmission rate and spectnun availability. One of the features of wireless communication systems is mobility and so the 5GHz WLAN stations are needed to be small size [21-[5]. On the other hand, the 2.4GHz band WLAN systems were staudardjzed earlier than the 5GHz band systems and have been already deployed in many areas. Therefore, WLAN stations are required to be operated in the dual band, both of 2.4GHz and 5GHz. And RF modules for the dual band W A N applications were reported recently [61-[71. Small size, low height and low cost are very important factors for the RF modules of dual band WLAN stations because the RF module are used as small cards of pemnal computers or mounted on the substrates in mobile phones. In this report, we used embedded fdters in the substrate, not chip filters on the substrates. That means not only small sue but also low height and low cost And the organic build-up substrates and flip chip technology were selected for the same purposes. This paper describes the design and experimental results about the RF module for dual band WLAN applications. has the variable attenuators for changing gain of the transceiver paths. IC2 is the up-conveaer and downmverter of IF signals and RF si&. And IC2 includes voltage controlled oscillator (VCO) and phase-locked loop (PLL) circuit for IF-local signals and RF-local signals. Y Crystal M r e n m ICl: 0rlhqon.l ModulldodD.mMulato~ IC2 Upman CMMrler and VCOlPLL Fig. 1. Block Diagram of RF Module for dual band WLAN In the transmitter path, power amplifiers (€'A's) for 2.4GH and 5GHz are used in order to boost the output power of IC2 to the proper level. 2.4GHz signals and 5GHz signals are supplied to a ...
In this paper, we present a high-efficiency 400 W power amplifier (PA) for a 6 MHz orthogonal frequency division multiplexing (OFDM) signal with a 10 dB peak-to-average power ratio (PAPR). To improve the efficiency of the PA at a 10 dB backoff from its saturated output power (PSAT), a dynamic drain voltage control is applied, which supplies two different drain voltages depending on the envelope of the OFDM signal. The PA is fabricated using a 400 W push-pull laterally diffused metal oxide semiconductor (LDMOS) field-effect transistor (FET) for an ultrahigh frequency (UHF) band. The drain current of a single LDMOS FET is 9.5 A at PSAT' The drain voltages used in the control are set to 40 V and 20 V. Measurement results indicate a power-added efficiency (PAE) in the case of dynamic drain voltage control of 34%, which is 15% higher than PAE at a drain voltage of 40 V. This is the highest output power of a PA with a dynamic drain voltage control to the best of our knowledge.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.