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Microwave Theory and Techniques, IEEE Transactions on

Issue 11 • Date Nov. 2009

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Displaying Results 1 - 25 of 30
  • Table of contents

    Publication Year: 2009 , Page(s): C1 - C4
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  • IEEE Transactions on Microwave Theory and Techniques publication information

    Publication Year: 2009 , Page(s): C2
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  • Compressive Receiver Using a CRLH-Based Dispersive Delay Line for Analog Signal Processing

    Publication Year: 2009 , Page(s): 2617 - 2626
    Cited by:  Papers (21)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1163 KB) |  | HTML iconHTML  

    A compressive receiver (CR) is presented utilizing a composite right/left-handed (CRLH) dispersive delay line (DDL) for analog signal processing applications. The CRLH DDL offers advantages such as arbitrary frequency of operation and wide bandwidth, filling a gap with competing DDL technologies. The presented CR system utilizes an impulse-driven CRLH DDL and mixer inversion for chirp generation required for real-time signal processing. At high frequencies, this eliminates frequency ramp generators. The CR is employed as a frequency discriminator and a tunable delay line with dispersion compensation. The simulation and experimental results fully validate the presented systems as proof-of-concept for high-frequency applications such as real-time Fourier transformers and signal analyzers. View full abstract»

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  • Inductive Compensation of High-Permittivity Coatings on Automobile Long-Range Radar Radomes

    Publication Year: 2009 , Page(s): 2627 - 2632
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (497 KB) |  | HTML iconHTML  

    A theoretical and practical investigation of polymer composites including paint layers as radomes for automotive long-range radar systems operating at 76.5 GHz is carried out. The materials in focus of this research are metallic base paints with a high concentration of metal, and hence, a high dielectric constant. A multilayered free-space measurement technique is presented to derive the dielectric properties of coatings with a thickness of several micrometers. The impact of the paint layers on the radar performance are discussed in this paper, and a narrowband technique is presented to compensate the reflection effects of critical paints. View full abstract»

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  • A CMOS Resistive Feedback Differential Low-Noise Amplifier With Enhanced Loop Gain for Digital TV Tuner Applications

    Publication Year: 2009 , Page(s): 2633 - 2642
    Cited by:  Papers (13)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (875 KB) |  | HTML iconHTML  

    A resistive feedback differential low-noise amplifier (LNA) with enhanced loop gain is implemented as a part of a digital TV (DTV) tuner using a 0.18-mum CMOS process. A voltage buffer having higher gain, higher linearity, and lower noise figure (NF) than those of the conventional differential source follower (DSF), which is called the differential hybrid voltage buffer (DHVB) in this paper, is designed by combining the common source amplifier and source follower. By adopting the DHVB with optimized performance as a voltage buffer of the conventional resistive feedback differential LNA, the loop gain of the LNA can be increased. This leads to a highly linear resistive feedback LNA with higher gain and lower NF compared to the conventional resistive feedback LNA. For the wide gain range, the proposed LNA includes the variable gain function based on the resistive attenuator employing the T-switch. The measurement results of the proposed LNA exhibit a maximum gain of 16 dB and a gain range of 50 dB. At maximum gain, the LNA shows an average NF of 2.8 dB, a third-order input-referred intercept point of -1 dBm, a second-order input-referred intercept point of 40 dBm, and S11 of under -9 dB in a frequency range from 48 to 860 MHz. The power consumption is 30.6 mW at a 1.8-V power supply and the chip area is 0.25 mm2. View full abstract»

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  • Comparative Analysis of VDMOS/LDMOS Power Transistors for RF Amplifiers

    Publication Year: 2009 , Page(s): 2643 - 2651
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (749 KB) |  | HTML iconHTML  

    A comparison between the RF performance of vertical and lateral power MOSFETs is presented. The role of each parasitic parameter in the assessment of the power gain, 1-dB compression point, efficiency, stability, and output matching is evaluated quantitatively using new analytical expressions derived from a ten-element model. This study reveals that the contribution of the parasitic parameter on degradation of performance depends upon the specific technology and generic perceptions of source inductance and feedback capacitance in VDMOS degradation may not always hold. This conclusion is supported by a detailed analysis of three devices of the same power rating from three different commercial vendors. A methodology for optimizing a device technology, specifically for RF performance and power amplifier performance is demonstrated. View full abstract»

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  • A 1.8-GHz CMOS Power Amplifier Using Stacked nMOS and pMOS Structures for High-Voltage Operation

    Publication Year: 2009 , Page(s): 2652 - 2660
    Cited by:  Papers (11)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1107 KB) |  | HTML iconHTML  

    A class-E power amplifier is proposed in this study. It uses both nMOS and pMOS as switching devices to reduce the voltage stress of each transistor. A voltage-combining scheme with nMOS and pMOS is proposed, and a transformer is designed using this scheme. The power amplifier is implemented in a 0.18-mum RF CMOS process. Measurements show a maximum output power of 30.2 dBm with 36.8% power-added efficiency at a 3.3-V supply voltage. The power amplifier sustains a supply voltage of up to 3.9 V. View full abstract»

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  • A 1.8-GHz 33-dBm P 0.1-dB CMOS T/R Switch Using Stacked FETs With Feed-Forward Capacitors in a Floated Well Structure

    Publication Year: 2009 , Page(s): 2661 - 2670
    Cited by:  Papers (10)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1269 KB) |  | HTML iconHTML  

    A 33-dBm P 0.1-dB single-pole double-throw antenna switch is designed and implemented using a standard 0.18-mum CMOS process at 1.8 GHz. An analysis shows a relation between parasitic junction capacitors and substrate resistance for low insertion loss (IL). The power-handling capability of the switch was also investigated through the voltage dividing mechanism through the substrate in the case of an ON-insertion loss-state NMOS switch implemented in a triple-well structure. A multistacked field-effect transistor (FET) structure with feed-forward capacitors in an Rx switch was chosen as the method of designing an antenna switch with high power-handling capability. Low IL of the switch in the multistacked FET structure is achieved by the optimization of layout and minimization of junction capacitors through the deep N-well bias. Allowance of a negative voltage swing at either the source or drain port is ensured by a floated well structure with a negatively biased P-well for each switch device of the multistacked FET structure. Intentional unequal division of the voltage swing level at each NMOS device by feed-forward capacitors with negative biases of the off-state switches helps to prevent channel formation in the off-state device. Experimental data shows that the proposed design achieves a 0.1-dB compression point at 33-dBm input power at 1.8 GHz with a negative bias supply to control the voltage at the off-state switches and the P -well of each device. The IL of the Tx switch is 0.5 and 0.73 dB at 900 MHz and 1.8 GHz, respectively. The Rx switch has 0.7- and 1.1-dB IL at 900 MHz and 1.8 GHz, respectively. In addition, a reliability issue related to antenna load mismatch was tested using a load-pull measurement setup. View full abstract»

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  • Distortion in Current Commutating Passive CMOS Downconversion Mixers

    Publication Year: 2009 , Page(s): 2671 - 2681
    Cited by:  Papers (21)  |  Patents (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (557 KB) |  | HTML iconHTML  

    CMOS passive mixer linearity is analyzed using a Volterra-series analysis and closed-form expressions for IIP2, two-tone IIP3, and cross-modulation IIP3 are presented, exhibiting dependence upon the mixer source and load impedances. Design guidelines are suggested for improving the mixer linearity performance. Accurate expressions are presented for the input impedance of an ideal passive mixer with an arbitrary load impedance. The calculations are in close agreement with the measured results and the simulated response. View full abstract»

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  • Vector Hole Punching Technique for OFDM Signals Using Circle-Tangent Shift and Unused Tones

    Publication Year: 2009 , Page(s): 2682 - 2691
    Cited by:  Papers (3)  |  Patents (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2001 KB) |  | HTML iconHTML  

    In order to combat high peak-to-average power ratio and poor power efficiency, drain modulated polar transmitter architectures have been proposed for orthogonal frequency-division multiplexing (OFDM) systems. However, this type of power amplifier architecture suffers from poor linearity in the low amplitude region, which often causes significant distortion to the system. In this paper, we propose a novel technique to introduce a vector hole into the constellation diagram of the OFDM signal, called vector hole punching, so that the envelope of the signal will avoid the origin region, thereby preventing the amplitude of the signal approaching zero, which dramatically improves the linearity of the system. This is achieved through a technique based on a combination of direct clipping, circle-tangent shifting, and the use of unused tones. Test results show a clear vector hole can be created by employing this technique that only slightly broadens the original spectrum and maintains a very low error vector magnitude. View full abstract»

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  • Effects of Spatial Dispersion on Reflection From Mushroom-Type Artificial Impedance Surfaces

    Publication Year: 2009 , Page(s): 2692 - 2699
    Cited by:  Papers (27)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (999 KB) |  | HTML iconHTML  

    In a spatially dispersive medium, the electric dipole moment of an inclusion cannot be related to the macroscopic electric field through a local relation. Several recent works have emphasized the role of spatial dispersion in wire media, and demonstrated that arrays of parallel metallic wires may behave very differently from a uniaxial local material with negative permittivity. Here, we investigate the effect of spatial dispersion on reflection properties of the mushroom structure introduced by Sievenpiper, based on local and nonlocal homogenization methods. The objective of this paper is to clarify the role of spatial dispersion in the mushroom structure and demonstrate that, under some conditions, it is suppressed. The metamaterial substrate, or metasurface is modeled as a wire medium covered with an impedance surface. Surprisingly, it is found that, in such a configuration, the effects of spatial dispersion may be nearly suppressed when the slab is electrically thin, and that the wire medium can be modeled very accurately using a local model. View full abstract»

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  • Characterization of Surface-Wave and Leaky-Wave Propagation on Wire-Medium Slabs and Mushroom Structures Based on Local and Nonlocal Homogenization Models

    Publication Year: 2009 , Page(s): 2700 - 2714
    Cited by:  Papers (22)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1913 KB) |  | HTML iconHTML  

    In this paper, a nonlocal homogenization model is proposed for the analysis of the spectrum of natural modes on sub-wavelength mushroom-type high-impedance surfaces composed of a capacitive grid connected to a grounded wire-medium (WM) slab. Modal characteristics of mushroom structures are studied in conjunction with the surface-wave and leaky-wave propagation on WM slabs based on local and nonlocal homogenization models, showing the importance of spatial dispersion (SD) in WM. It is shown that mushroom structures support proper real (bound) forward and backward modes, whose dispersion determines the stopband properties of the mushroom structure, and proper (exponentially decaying from the surface) and improper (exponentially growing from the surface) complex leaky-wave modes related to the backward and forward radiation, respectively. Results obtained by different homogenization models are compared leading to important conclusions. Specifically, an interesting observation concerns the mushroom structures with short vias, wherein the SD of the WM slab is significantly reduced, and the results of local and nonlocal homogenization models are in excellent agreement. View full abstract»

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  • Enhanced Periodic Structure Analysis Based on a Multiconductor Transmission Line Model and Application to Metamaterials

    Publication Year: 2009 , Page(s): 2715 - 2726
    Cited by:  Papers (4)  |  Patents (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (962 KB) |  | HTML iconHTML  

    We propose to model periodic structures by equivalent multiconductor transmission lines (MTLs). The developed technique is based on a multimodal representation of the periodic structure unit cell, such as required for periodically loaded MTLs and periodically loaded waveguides with higher order evanescent mode interaction between cells. Compared to commonly employed periodic structure analyses which only provide the dispersion diagram, the proposed method provides all the parameters needed to accurately model the excitation and matching of finite-size periodic structures. The usefulness of the method is illustrated by means of two examples of negative-refractive-index metamaterials. First, a loaded MTL known as the shielded mushroom is analyzed. The proposed technique allows addressing the fundamental issue of the excitation of the different propagating Bloch modes supported by such a structure. Second, a split-ring resonator and wire metamaterial is analyzed. The method is shown to accurately represent the coupling between cells, thereby providing an enhanced design tool compared to the dominant-mode analysis usually employed for this type of metamaterials. View full abstract»

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  • A New Training Approach for Parametric Modeling of Microwave Passive Components Using Combined Neural Networks and Transfer Functions

    Publication Year: 2009 , Page(s): 2727 - 2742
    Cited by:  Papers (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1690 KB) |  | HTML iconHTML  

    This paper presents a novel technique to develop combined neural network and transfer function models for parametric modeling of passive components. In this technique, the neural network is trained to map geometrical variables onto coefficients of transfer functions. A major advance is achieved in resolving the discontinuity problem of numerical solutions of the coefficients with respect to the geometrical variables. Minimum orders of transfer functions for different regions of geometrical parameter space are identified. Our investigations show that varied orders used for different regions result in the discontinuity of coefficients. The gaps between orders are bridged by a new order-changing module, which guarantees the continuity of coefficients and simultaneously maintains the modeling accuracy through a neural network optimization process. This technique is also expanded to include bilinear transfer functions. Once trained, the model provides accurate and fast prediction of the electromagnetic behavior of passive components with geometrical parameters as variables. Compared to conventional training methods, the proposed method allows better accuracy in challenging applications involving high-order transfer functions, wide frequency range, and large geometrical variations. Three examples including parametric modeling of slotted patch antennas, bandstop microstrip filters, and bandpass coupled-line filters are examined to demonstrate the validity of this technique. View full abstract»

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  • High-Pass Filtering Characteristics of Transmission-Line Combs

    Publication Year: 2009 , Page(s): 2743 - 2752
    Cited by:  Papers (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1107 KB) |  | HTML iconHTML  

    The filtering characteristics of a transmission line loaded at regular intervals with closely spaced shorted stubs are investigated theoretically, experimentally, and by means of rigorous electromagnetic simulations. It is shown that this periodic structure exhibits waveguide-like behavior with a first passband whose width is a function of the characteristic impedance and pitch of the stubs. It is also shown that when the stub pitch vanishes, the structure degenerates into a waveguide whose mode-cutoff frequencies correspond to a shorted-stub length that is an odd multiple of the wavelength. These features enable the design of compact high-pass filters, and make possible cutoff-frequency hopping and tuning. Implementations in microstrip are shown that demonstrate desirable characteristics such as wide bandwidth, low insertion loss, reduced size, easy integration with planar circuits, as well as common and differential-mode filtering, making such structures attractive for use in low-cost microwave and millimeter-wave applications. View full abstract»

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  • High Aspect-Ratio Coplanar Waveguide Wideband Bandpass Filter With Compact Unit Cells

    Publication Year: 2009 , Page(s): 2753 - 2760
    Cited by:  Papers (8)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2759 KB) |  | HTML iconHTML  

    This paper introduces a micromachined thick single-metal-layer high aspect-ratio coplanar waveguide (CPW) wideband bandpass filter with compact unit cells based on the electromagnetic bandgap (EBG) concept. The filter is miniaturized as a result of using the EBG concept in design, and also by realizing high aspect-ratio structures with polymer-based deep X-ray lithography fabrication. Cascaded unit cells in the EBG model consist of capacitive and inductive parallel periodically loaded transmission lines, which determine the filter bandwidth. Compact unit cells are realized by using high aspect-ratio CPW stepped-impedance resonators. The main advantage of this approach is that the high aspect-ratio CPW structures make short unit cells practically realizable, resulting in a compact filter structure. A bandpass filter with 47% bandwidth is designed and fabricated using deep X-ray lithography, and the performance and physical size is compared to a conventional quarter-wavelength-based admittance inverter filter. View full abstract»

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  • Planar Probe Coaxial-Waveguide Power Combiner/Divider

    Publication Year: 2009 , Page(s): 2761 - 2767
    Cited by:  Papers (16)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (864 KB) |  | HTML iconHTML  

    A novel axially symmetric oversized coaxial waveguide power combiner/divider, which utilizes a planar probe array to transform multiway input to a central oversized coaxial waveguide, is presented in this paper. The use of a coaxial waveguide allows standard transverse electromagnetic design theory to be used, and the characteristics of the coaxial taper transition and the planar probe array are analyzed in detail. A design procedure is also established for the structure. A ten-way planar probe coaxial-waveguide power combiner/divider over the Ku-band is designed and measured. The measured results show a reasonable agreement with the simulated results. The measured 15-dB return-loss bandwidth is approximately 4.3 GHz, and a maximum amplitude imbalance of plusmn 1 dB and a phase imbalance of plusmn5deg are observed in the 11.5-16-GHz band. Furthermore, the isolation between the peripheral ports is also discussed. View full abstract»

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  • Reconfigurable CMOS Tuners for Software-Defined Radio

    Publication Year: 2009 , Page(s): 2768 - 2774
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (905 KB) |  | HTML iconHTML  

    A reconfigurable tuner is demonstrated by using a low-loss shielded coplanar waveguide transmission line periodically loaded with CMOS transistor switches in series with capacitors. The switch-capacitor combination is used to change the local impedance of the transmission line in a binary fashion. It achieves a higher capacitance ratio (by 60%), less transmission loss (by 40%), higher quality factor (by 100%), and subsequently wider bandwidth and better Smith impedance chart coverage compared to optimized CMOS varactors realized in the same technology. The 5-16 GHz tuner demonstrated here is implemented in a standard 0.13-mum CMOS technology and can be configured to 220 different impedances through an integrated 20-bit shift register. View full abstract»

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  • A Slot-Loaded Composite Right/Left-Handed Transmission Line for a Zeroth-Order Resonant Antenna With Improved Efficiency

    Publication Year: 2009 , Page(s): 2775 - 2782
    Cited by:  Papers (11)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1587 KB) |  | HTML iconHTML  

    In this paper, a new composite right/left-handed transmission line (CRLH-TL) with equilateral slots is proposed for efficiency-improved zeroth-order resonant antennas. A 1-D infinitesimal equivalent transmission line circuit model is derived, and the characteristic impedance and dispersive relation are theoretically computed. Based on the isotropic arranged unit cells of the slot-loaded composite right/left-handed transmission line (SL CRLH-TL), 2-D zeroth-order resonators are designed for planar magnetic monopole antenna applications. The SL CRLH-TL provides the zeroth-order resonance with some degradation of the quality factor. Therefore, a highly efficient radiating resonator can be designed with higher gain at the zeroth-order frequency. The theoretical approach was verified by the experimental results. The radiation efficiency was improved by up to 45.6% for the nine-rectangular zeroth-order resonant antenna and 21.4% for the seven-hexagonal zeroth-order resonant antenna without degrading the radiating performance. Moreover, the antenna gains of these two antennas were enhanced by 7.56 and 6.31 dB, respectively, due to the increase of the radiation efficiency. View full abstract»

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  • Broadband Micro-Coaxial Wilkinson Dividers

    Publication Year: 2009 , Page(s): 2783 - 2789
    Cited by:  Papers (13)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1495 KB) |  | HTML iconHTML  

    This paper presents several micro-coaxial broadband 2 : 1 Wilkinson power dividers operating from 2 to 22 GHz, a 11 : 1 bandwidth. Circuits are fabricated on silicon with PolyStrata technology, and are implemented with 650 mum times 400 mum air-supported micro-coaxial lines. The measured isolation between the output ports is greater than 11 dB and the return loss at each port is more than 13 dB over the entire bandwidth. The footprints of these dividers can be miniaturized due to the high isolation between adjacent coaxial lines and their tight bend radius. For higher power handling, larger lines with a cross section of 1050 mum times 850 mum are also demonstrated. The effect of mismatch at the output ports is investigated in order to find the power loss in the resistors. View full abstract»

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  • Electrical Prism: A High Quality Factor Filter for Millimeter-Wave and Terahertz Frequencies

    Publication Year: 2009 , Page(s): 2790 - 2799
    Cited by:  Papers (8)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1542 KB) |  | HTML iconHTML  

    A 2-D electrical filter is introduced that is compatible with today's conventional integrated circuit processes. The rich 2-D propagation properties of the medium are used to introduce a novel high quality factor filter called an electrical prism. The proposed filter shows a quality factor much larger than the quality factor of the individual components at high millimeter-wave and terahertz frequencies. This structure also provides a negative effective index in a low-pass LC lattice. Based on this idea, we show filters with quality factors of 130 at 230 GHz and 420 at 460 GHz consisting of elements with the quality factor of 10 and 20, respectively. The effect of component loss on the filter quality factor is discussed in this paper. The negative effective index and the filter behavior of the lattice is verified by measuring a prototype on a CMOS process at 32-40 GHz. There is good agreement among the theory, simulation, and experimental results. View full abstract»

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  • A Reformulation and Stability Study of TRL and LRM Using S -Parameters

    Publication Year: 2009 , Page(s): 2800 - 2807
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (518 KB) |  | HTML iconHTML  

    This paper derives a unified thru, reflect, match (TRL) and line, reflect, match (LRM) calibration algorithm using S-parameters instead of traditional T-parameters. The advantage of this approach is that we get a solution where the LRM is an integral part of the TRL algorithm. The expression for the transmission coefficient of the line standard has the convenient property that, in many cases, the transmission coefficient is obtained directly without a need for a root choice. View full abstract»

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  • Novel SPICE Compatible Partial-Element Equivalent-Circuit Model for 3-D Structures

    Publication Year: 2009 , Page(s): 2808 - 2815
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (743 KB) |  | HTML iconHTML  

    This paper presents a novel SPICE compatible partial-element equivalent-circuit (PEEC) model for general linear medium. In this new model, the magnetized current in conductive magnet and fictitious magnetized current through the magnetic interface are considered, as well as conduction current in conductor and polarization currents in a dielectric, to model the magnetization and conduction loss effect of a conductive magnet. Corresponding equivalent circuits are derived. The magnetic field couplings between inductive cells are taken into account as current controlled current sources to avoid the time-consuming calculation of time derivatives. The new model was applied in 3-D magnetically enhanced inductor structure analysis and antenna modeling. Obtained results are compared with those obtained from commercial numerical electromagnetic simulation software and show good agreement. View full abstract»

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  • Improved Radio-Over-Fiber Transponder With Multistage Automatic Gain Control

    Publication Year: 2009 , Page(s): 2816 - 2823
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1238 KB) |  | HTML iconHTML  

    In this paper, improved transponders with multistage automatic gain control (AGC) for radio-over-fiber-based distributed antenna systems are presented. Error vector magnitude performance measurements for both uplink and downlink paths are carried out to verify the feasibility of applying this system for IEEE 802.11g signal transmission. The developed conventional radio-over-fiber system shows its capability of supporting the wireless local area network signal transmission for an input dynamic range of approximately 14 dB. The improved radio-over-fiber systems with a single- and two-stage AGC are also demonstrated to have a better input dynamic range of 27 dB and more than 37 dB, respectively. The error vector magnitude for the case with a two-stage AGC is much better than that with a single-stage AGC. View full abstract»

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  • Frequency Scalable Model for MEMS Capacitive Shunt Switches at Millimeter-Wave Frequencies

    Publication Year: 2009 , Page(s): 2824 - 2833
    Cited by:  Papers (7)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2332 KB) |  | HTML iconHTML  

    This paper presents an approach to RF microelectromechanical systems (MEMS) capacitive shunt switch design from K-band up to W-band based on the scalability of the RF MEMS switch with frequency. The parameters of the switch's equivalent-circuit model also follow scaling rules. The measurement results of the fabricated switches show an excellent agreement with simulations that allow to validate the MEMS model in the entire band from 20 up to 94 GHz. This model is going to be used in the phase shifter circuit design for antenna array applications. The first 60-GHz phase shifter results are also reported here. View full abstract»

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The IEEE Transactions on Microwave Theory and Techniques focuses on that part of engineering and theory associated with microwave/millimeter-wave components, devices, circuits, and systems involving the generation, modulation, demodulation, control, transmission, and detection of microwave signals. This includes scientific, technical, and industrial, activities. Microwave theory and techniques relates to electromagnetic waves usually in the frequency region between a few MHz and a THz; other spectral regions and wave types are included within the scope of the Society whenever basic microwave theory and techniques can yield useful results. Generally, this occurs in the theory of wave propagation in structures with dimensions comparable to a wavelength, and in the related techniques for analysis and design..

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