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Design and modeling of an ultra-wideband low-noise distributed amplifier in InP DHBT technology
T. Shivan, E. Kaule, M. Hossain, R. Doerner, T. Johansen, D. Stoppel, S. Boppel, W. Heinrich, V. Krozer, M. Rudolph
This paper reports on an ultra-wideband low-noise distributed amplifier (LNDA) in a transferred-substrate InP double heterojunction bipolar transistor (DHBT) technology which exhibits a uniform low-noise characteristic over a large frequency range. To obtain very high bandwidth, a distributed architecture has been chosen with cascode unit gain cells. Each unit cell consists of two cascode-connecte
Design and characterization of a 6?18 GHz GaN on SiC high-power amplifier MMIC for electronic warfare
Eduardo Oreja Gigorro, Emilio Delgado Pascual, Juan José Sánchez Martínez, María Luz Gil Heras, Virginia Bueno Fernández, Antonio Bódalo Márquez, Jesús Grajal
A 6?18 GHz high-power amplifier (HPA) design in GaN on SiC technology is presented. This power amplifier consists of a two-stage corporate amplifier with two and four transistors, respectively. It has been fabricated on UMS using their 0.25 µm gate length process, GH25. A study of the suitable attachment method and measurement on wafer and on jig are detailed. This HPA exhibits an averaged output
Novel DC-biasing circuits with arbitrary harmonics-control capability for compact high-efficiency power amplifiers
Shinichi Tanaka, Tomoya Oda, Kento Saiki
The next generation mobile communication systems impose challenging performance, size, and cost requirements on the power amplifiers (PAs). This paper presents novel DC-biasing circuits, which are compact and yet can control the harmonics almost arbitrarily. The proposed circuit consists of a composite right-/left-handed (CRLH) transmission line (TL) stub, of which the size and harmonics-control f
Highly compact GaN-based all-digital transmitter chain including SPDT T/Rx switch for massive MIMO applications
Florian Hühn, Andreas Wentzel, Wolfgang Heinrich
This paper presents a fully digital transmitter chain from baseband to antenna, including a modulator, two truly digital (i.e. fully switched) microwave power amplifiers and a transmit/receive switch. Both, amplifier and switch monolithic microwave integrated circuits were implemented in a GaN HEMT process. The novel amplifier design provides greatly reduced complexity, needing only three voltage
TDOA estimation using a pair of synchronized anchor nodes
Vitomir Djaja-Josko, Jerzy Kolakowski, Jozef Modelski
Nowadays, as indoor localization is getting more popular, there is a growing need for reliable and accurate techniques of position determination. Recently, ultrawideband (UWB)-based systems are gaining popularity, since they make achieving positioning errors in the range of dozens of centimeters or even single centimeters, possible. The Time Difference of Arrival (TDOA)-based systems are especiall
Circular polarization realization in array antennas by a modified sequential phase feeding mechanism of linearly polarized elements
A. Haghshenas, CH. Ghobadi, J. Nourinia, M. Majidzadeh, S. Mohammadi-Asl
Novel designs of a circularly polarized 2 × 2 and 4 × 4 slot array antennas (CPSAAs) are proposed. Sequential phase feed network composed of a section of 270° and four strips is utilized to feed the array structures. Array elements are simple linearly polarized wide slot antennas (WSAs) composed of simple radiating patches with truncation on four corners and slotted ground plane on substrate backs
Low-profile, extremely wideband, dual-band-notched MIMO antenna for UWB applications
Ankan Bhattacharya, Bappadittya Roy, Rafael F. S. Caldeirinha, Anup K. Bhattacharjee
In this article, an extremely wideband, isolation-enhanced, low-profile ?Multiple-Input-Multiple-Output? (MIMO) antenna along with dual-band-notched features has been investigated. The antenna proposed herein, possesses two mutually orthogonal staircase-etched radiators for achieving a wide bandwidth. The radiating elements are placed mutually perpendicular in order to achieve polarization diversi
Compact planar ultra-wideband antenna with dual notched band for WiMAX and WLAN
A. K. M. Ariful H. Siddique, Rezaul Azim, Mohammad T. Islam
A compact planar ultra-wideband (UWB) antenna with WiMAX and WLAN notched band is presented in this paper. The presented antenna consists of a rectangular patch and slotted partial ground plane and fed by a microstrip feed line. The volumetric size of the antenna is 30 mm × 22 mm × 1.6 mm. Method of moment-based simulation technology is used to simulate and analyze the characteristics of the anten
A wideband, single layer reflectarray antenna with cross loop and square ring slot loaded patch elements
Lingasamy Veluchamy, Gulam Nabi Alsath Mohammed, T. Selvan Krishnasamy, Rajeev Jyoti
This paper presents the design and analysis of a wideband X/Ku and Ku band reflectarray antenna. The proposed unit cell of the reflectarray antenna comprises a patch loaded with two distinct slots, viz. a square ring and a cross loop, printed on a low loss substrate, which is backed by a foam-loaded ground plane. The unit cell element offers a linear and large dynamic reflection phase range, which
Low profile dual band-stop super wideband printed monopole antenna with polarization diversity
Murli Manohar, Rakhesh Singh Kshetrimayum, Anup Kumar Gogoi
A low profile super-wideband polarization diversity printed monopole antenna with dual band-notched characteristics is presented the first time. The designed antenna comprises two arched shaped radiating elements with two triangular tapered microstrip feed lines (TTMFL) and two arched shaped partial ground planes, which covers an enormously wide impedance bandwidth (BW) from 1.2 to 25 GHz (ratio B
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