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《Microwave and Wireless Components Letters, IEEE》2008,18(8):533-535
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de Paco P. Villarino R. Junkin G. Menendez O. Corrales E. Parron J. 《Microwave and Wireless Components Letters, IEEE》2007,17(8):607-609
The concept of composite right left-handed transmission lines provides for one additional degree of freedom in realizing arbitrary dual-band frequency response devices. In this letter, an arbitrary dual-band operation mixer, based on the classical balanced mixer topology is proposed. The prototype demonstrates the mixer performance for a ratio of 2.5 between the two operation bands (860 MHz and 2,150 MHz). The conversion losses are better than 8.5 dB in both bands. 相似文献
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设计了一种基于复合左右手传输线结构的零阶谐振天线,讨论了零阶谐振天线的工作原理。使用Ansoft Designer软件仿真和优化了中心频率为1.8 GHz,单元组为5单元、7单元、9单元单元和11单元的零阶谐振天线。文中给出了零阶谐振天线的具体设计尺寸和由9单元构成的零阶谐振天线的仿真图,其天线增益为8.7 dBi,在中心频率处电压反射系数为1.28。基于复合左右手传输线结构设计的零阶谐振天线其尺寸和损耗都比微带阵列天线小。 相似文献
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Propagation and radiation characteristics of 1-D dielectric-resonator-based composite right/left-handed metamaterial structures with open mesh plates are investigated as a function of configuration parameters. The complex effective permittivity and permeability are estimated from the scattering parameters of the unit-cell structure. Based on this configuration, the single-mode transmission line is designed and the backfire-to-endfire frequency-scanned leaky wave antenna is implemented. It is found from numerical simulations that the 30-cell leaky wave antenna has a gain of 10 dBi with a scanning angle of over 90deg covering backfire-to-endfire directions. The measurement results show as wide beam-steering angles as numerically predicted. 相似文献
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《Microwave and Wireless Components Letters, IEEE》2009,19(12):804-806
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Chao-Hsiung Tseng Chih-Lin Chang 《Microwave and Wireless Components Letters, IEEE》2008,18(4):269-271
A new balanced amplifier (BA) using metamaterial-based quadrature power splitters (QPSs) is presented in this letter. Instead of using conventional 90 couplers, the developed BA is implemented by two parallel amplifiers with broadband metamaterial-based QPSs at input and output ends. Since the QPSs can provide a broadband quadrature phase difference between two outputs, the input/output reflections from two amplifiers can be effectively cancelled over a wide bandwidth. The developed BA demonstrates the input/output return loss of better than 10 dB from 1.2 to 3.5 GHz with 97.9% relative bandwidth. 相似文献
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《Microwave Theory and Techniques》2009,57(6):1572-1580
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《Applied Superconductivity, IEEE Transactions on》2006,16(3):1893-1897
This paper implements wideband, low-loss, and via-free left-handed transmission lines (LH-TLs) using superconductor thin films. Introducing superconductors greatly reduces the loss inherited in the constituent series capacitors and shunt inductors of such planar LH-TLs. The measured results agree very well with design expectations. The bandwidth of left-handed characteristics is 4.9–10.9 GHz, with a minimum insertion loss of 0.03 dB at 30 K. Open-ended LH-TL resonators are also characterized at the different harmonics; of special interest are those with zero or negative phase constants, which are not possible when using any conventional transmission lines. Temperature-dependence measurements of the LH-TLs reveal the effect of the superconductor kinetic inductance. 相似文献
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A broadband quadrature power splitter (QPS) is developed using the metamaterial transmission line (MM TL). It consists of a Wilkinson power divider and two phase-adjusting TLs, namely a MM TL and a microstrip (MS). The slope of the phase-response curve of the MM TL is synthesized to be the same as that of the MS along with the 90deg phase increment at two design frequencies. Hence, the broadband quadrature phase difference over the desired frequency range can be obtained. In this letter, the QPS is developed at the center frequency of 2 GHz. Over the frequency range of 1.1-3.5 GHz, an amplitude imbalance of less than 0.9 dB and a phase error of less than plusmn5deg have been experimentally demonstrated. 相似文献
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《Microwave and Wireless Components Letters, IEEE》2006,16(11):585-587
The novel concept of dual composite right/left-handed (D-CRLH) transmission line metamaterial is introduced. The D-CRLH is the "dual" of the conventional CRLH in the sense that it has a series parallel (instead of series) LC tank and a shunt series (instead of parallel) LC tank. This topological duality results in dual properties. The D-CRLH indeed exhibits its left-handed (LH) band at high frequencies and its right-handed (RH) band at low frequencies and is of stop-band nature, in opposition to the CRLH which is low-frequency-LH/high-frequency-RH and pass-band. The so-called balanced condition is still valid in the D-CRLH for broadband matching. However, phase origin is at dc and infinity instead, as at the LH-RH transition, and the gap between the RH and LH bands cannot be closed up in practical implementations. In contrast, the D-CRLH provides an unlimited LH bandwidth. This letter presents the homogeneous and LC-network transmission parameters and the fundamental dispersion/impedance properties of the D-CRLH 相似文献
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基于复合左右手传输线技术研究设计超小型的天线,通过对复合左右手传输线结构的适当调整获得一个零阶谐振天线,此时天线的工作频率不再依赖于天线的几何尺寸,而只与构成左手传输线的电感与电容相关,从而可大大降低天线的几何尺寸。文中基于复合左右手传输线设计了一款小型天线,使其可以工作在ISM频段,能够满足无线局域网(2.4~2.4835GHz)的要求。 相似文献
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《Microwave and Wireless Components Letters, IEEE》2006,16(11):624-626
An enhanced composite right/left-handed (CRLH) transmission line (TL) is presented in this letter. This TL, designed in microstrip technology, is implemented by means of a new improved interdigital capacitor (IDC), the so-called wire bonded IDC (WBIDC). The use of the WBIDC broadens the frequency band where the CRLH TL can be considered as a TL. A conventional 70-Omega CRLH TL (using IDCs) has been compared, by full-wave simulation and measurements, with its enhanced counterpart (using WBIDCs). In addition, this enhanced CRLH TL has been used to design a CRLH diplexer which presents several advantages over standard CRLH coupled lines (using IDCs). The diplexer response has been verified by means of a full-wave electromagnetic solver 相似文献
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