scholarly journals The Systematic Design of Non-commensurate Impedance Matching Tapers for Ultra Wideband Gradient-Index (GRIN) Lens Antennas

2021 ◽  
pp. 1-1
Author(s):  
Wei Wang ◽  
Nicolas Garcia ◽  
Jonathan Chisum
Keyword(s):  
Impedance Matching ◽  
Ultra Wideband ◽  
Gradient Index ◽  
Systematic Design ◽  
Lens Antennas ◽  
Grin Lens

scholarly journals Ultra-Wideband Dielectric Lens Antennas for Beamsteering Systems

2019 ◽  
Vol 2019 ◽  
pp. 1-8
Author(s):  
Renan Alves dos Santos ◽  
Gabriel Lobão da Silva Fré ◽  
Luís Gustavo da Silva ◽  
Marcelo Carneiro de Paiva ◽  
Danilo Henrique Spadoti
Keyword(s):  
Antenna Array ◽  
Ultra Wideband ◽  
Printed Antennas ◽  
Lens Antennas ◽  
Dielectric Lens ◽  
Dielectric Lenses

This paper presents a high-directivity ultra-wideband beamsteering antenna array. An innovative beamsteering system based on hemispherical dielectric lenses fed by a set of different printed antennas is proposed. Diversity of signals in different spatial positions can be radiated at the same time. A prototype was manufactured and characterized, operating in a bandwidth varying from 8 GHz to 12 GHz with gain up to 13 dBi.

Selectivity and in-band impedance enhancement of a compact slot antenna with defected ground structures

2019 ◽  
Vol 11 (10) ◽  
pp. 1010-1016
Author(s):  
Hailong Yang ◽  
Xiaoli Xi ◽  
Lili Wang ◽  
Yuchen Zhao ◽  
Xiaomin Shi
Keyword(s):  
Reflection Coefficient ◽  
Impedance Matching ◽  
Ultra Wideband ◽  
Band Edge ◽  
Slot Antenna ◽  
Defected Ground Structure ◽  
Pass Filter ◽  
Low Pass Filter ◽  
Uwb Antennas ◽  
Low Pass

AbstractIn this study, a new ultra-wideband (UWB) band-edge selectivity antenna with a modified radiation slot using defected ground structure (DGS) is presented to obtain bandpass filtering reflection coefficient and gain performance. The well-designed DGS is designed on backside metallic of the substrate and can be seen as a low-pass filter that provides a good roll-off at a higher frequency. By connecting the DGS and the stepped slot and making them merge with each other, good cut-off property in the upper passband and better in-band impedance characteristics are obtained. Measured results show that the proposed design not only shows good band-edge selectivity in reflection coefficient and gain performance but also has a good impedance matching of −13.5 dB reflection coefficients and a good radiation efficiency of 90% in the operating frequencies. The measured bandwidth defined with the reflection coefficient less than −10 dB is from 3.1–11.2 GHz. Furthermore, the size of the filtering UWB antenna is 22 mm × 12 mm, which is smaller than many individual UWB antennas and UWB filters.

scholarly journals Compact Liquid Crystal Based Tunable Band-Stop Filter with an Ultra-Wide Stopband by Using Wave Interference Technique

2017 ◽  
Vol 2017 ◽  
pp. 1-11 ◽  
Author(s):  
Longzhu Cai ◽  
Huan Xu ◽  
Daping Chu
Keyword(s):  
Liquid Crystal ◽  
Impedance Matching ◽  
Wide Frequency Range ◽  
Ultra Wideband ◽  
New Wave ◽  
Wave Interference ◽  
Rejection Level ◽  
Band Stop Filter ◽  
The Individual ◽  
Uwb Applications

A wave interference filtering section that consists of three stubs of different lengths, each with an individual stopband of its own central frequency, is reported here for the design of band-stop filters (BSFs) with ultra-wide and sharp stopbands as well as large attenuation characteristics. The superposition of the individual stopbands provides the coverage over an ultra-wide frequency range. Equations and guidelines are presented for the application of a new wave interference technique to adjust the rejection level and width of its stopband. Based on that, an electrically tunable ultra-wide stopband BSF using a liquid crystal (LC) material for ultra-wideband (UWB) applications is designed. Careful treatment of the bent stubs, including impedance matching of the main microstrip line and bent stubs together with that of the SMA connectors and impedance adaptors, was carried out for the compactness and minimum insertion and reflection losses. The experimental results of the fabricated device agree very well with that of the simulation. The centre rejection frequency as measured can be tuned between 4.434 and 4.814 GHz when a biased voltage of 0–20 Vrms is used. The 3 dB and 25 dB stopband bandwidths were 4.86 GHz and 2.51 GHz, respectively, which are larger than that of other recently reported LC based tunable BSFs.

scholarly journals CMOS Ultra-Wideband Low Noise Amplifier Design

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
K. Yousef ◽  
H. Jia ◽  
R. Pokharel ◽  
A. Allam ◽  
M. Ragab ◽  
...  
Keyword(s):  
Impedance Matching ◽  
Cmos Technology ◽  
Low Noise ◽  
Low Noise Amplifier ◽  
Ultra Wideband ◽  
Output Impedance ◽  
Integrated Inductor ◽  
Technology Process ◽  
Amplifier Design ◽  
Noise Amplifier

This paper presents the design of ultra-wideband low noise amplifier (UWB LNA). The proposed UWB LNA whose bandwidth extends from 2.5 GHz to 16 GHz is designed using a symmetric 3D RF integrated inductor. This UWB LNA has a gain of 11 ± 1.0 dB and a NF less than 3.3 dB. Good input and output impedance matching and good isolation are achieved over the operating frequency band. The proposed UWB LNA is driven from a 1.8 V supply. The UWB LNA is designed and simulated in standard TSMC 0.18 µm CMOS technology process.

scholarly journals Reconfigured and Notched Tapered Slot UWB Antenna for Cognitive Radio Applications

2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
Tamer Aboufoul ◽  
Akram Alomainy ◽  
Clive Parini
Keyword(s):  
Cognitive Radio ◽  
Impedance Matching ◽  
Ultra Wideband ◽  
Slot Antenna ◽  
Total Efficiency ◽  
Back Side ◽  
Radiation Patterns ◽  
Uwb Antenna ◽  
Design Concepts ◽  
Specific Frequency

A compact reconfigurable and notched ultra-wideband (UWB) tapered slot antenna (TSA) is presented. The antenna reconfiguration operation principle relies on 2 mechanisms: in the first mechanism a resonator parasitic microstrip line electrically coupled to the TSA is used to notch the TSA at a specific frequency and the second mechanism relies on changing the input impedance matching of the antenna by means of changing the length of a stub line extended from an additional tiny partial ground on the back side of the antenna. The reflection coefficient, radiation patterns, and gain simulations and measurements for the proposed antenna are presented to verify the design concepts featuring a very satisfactory performance. Total efficiency simulations and measurements are also presented to highlight the filtering performance of the reconfigured antenna. When the antenna was reconfigured from the UWB to work into multiple frequency bands, the radiation patterns were still the same and the total peak gain has slightly improved compared to the UWB case. In addition, when the antenna operated in the notched mode, the gain has significantly dropped at the notch frequency. The simplicity and flexibility of the proposed multimode antenna make it a good candidate for future cognitive radio front ends.

scholarly journals A New Design Method for Ultrawideband Microstrip-to-Suspended Stripline Transitions

2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Young-Gon Kim ◽  
Kang Wook Kim
Keyword(s):  
Conformal Mapping ◽  
Insertion Loss ◽  
Design Method ◽  
Impedance Matching ◽  
Characteristic Impedance ◽  
Ultra Wideband ◽  
Efficient Design ◽  
Em Simulation ◽  
Simulation Results ◽  
Analytical Expressions

A clear and efficient design method for ultra-wideband microstrip-to-suspended stripline transition, which is based on the analytical expressions of the whole transitional structure, is presented. The conformal mapping is applied to obtain the characteristic impedance of the transitional structure within 2.85% accuracy as compared with the EM-simulation results. The transition is designed to provide broadband impedance matching and smooth field conversion. The implemented transition performs less than 0.6 dB insertion loss per transition for frequencies up to 30 GHz.

Design and modeling of an ultra-wideband low-noise distributed amplifier in InP DHBT technology

2019 ◽  
Vol 11 (7) ◽  
pp. 635-644 ◽  
Author(s):  
T. Shivan ◽  
E. Kaule ◽  
M. Hossain ◽  
R. Doerner ◽  
T. Johansen ◽  
...  
Keyword(s):  
Noise Figure ◽  
Impedance Matching ◽  
Low Noise ◽  
Ultra Wideband ◽  
Frequency Range ◽  
Collector Current ◽  
Noise Sources ◽  
Distributed Amplifier ◽  
Double Heterojunction ◽  
High Bandwidth

AbstractThis 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-connected transistors with 500 nm emitter length and ft/fmax of ~360/492 GHz, respectively. Due to optimum line-impedance matching, low common-base transistor capacitance, and low collector-current operation, the circuit exhibits a low-noise figure (NF) over a broad frequency range. A 3-dB bandwidth from 40 to 185 GHz is measured, with an NF of 8 dB within the frequency range between 75 and 105 GHz. Moreover, this circuit demonstrates the widest 3-dB bandwidth operation among all reported single-stage amplifiers with a cascode configuration. Additionally, this work has proposed that the noise sources of the InP DHBTs are largely uncorrelated. As a result, a reliable prediction can be done for the NF of ultra-wideband circuits beyond the frequency range of the measurement equipment.

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