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Showing papers on "Coplanar waveguide published in 1995"


Patent
30 Aug 1995
TL;DR: In this paper, the first dielectric waveguide is mounted coaxially within the distal end portion of the metal waveguide and tapering outwardly toward the inwardly tapering portion.
Abstract: A microwave antenna comprises a single moded metal waveguide tapering inwardly to a cutoff dimension near the distal end thereof. The antenna also comprises a first solid dielectric waveguide mounted coaxially within the distal end portion of the metal waveguide and tapering outwardly toward the inwardly tapering portion of the metal waveguide. The first dielectric waveguide extends beyond the distal end of the metal waveguide in the axial direction. The antenna also comprises a second dielectric waveguide surrounding the first dielectric waveguide beyond the distal end of the metal waveguide and having a dielectric constant lower than the dielectric constant of the first dielectric waveguide. A distal end portion of the first dielectric waveguide tapers inwardly toward the axis thereof, to launch signals propagating toward the distal end of the first dielectric waveguide into the second dielectric waveguide.

190 citations


Patent
03 Jan 1995
TL;DR: In this paper, a passive element (10) has an insulating layer (12) overlying a silicon substrate (14), and a metal layer (16) comprising a signal line (18) and a groundplane (20) is disposed overlying the groundplane.
Abstract: A passive element structure and method for a microwave integrated circuit reduces signal propagation losses. In one approach, a passive element (10) has an insulating layer (12) overlying a silicon substrate (14). A metal layer (16) comprising a signal line (18) and a groundplane (20) is disposed overlying the insulating layer (12), and at least a portion of the metal layer (16) contacts the substrate (14) through at least one opening (22, 24) in the insulating layer (12). The silicon substrate (14) has a resistivity greater than 2,000 ohm-cm, and the passive element (10) preferably carries signals having frequencies greater than 500 MHz. Signal losses in the passive element (10) are minimized because the charge density at the surface (15) of the substrate (14) underlying the metal layer (16) is significantly reduced. In one example, the passive element (10) is a coplanar waveguide transmission line.

155 citations


Journal ArticleDOI
TL;DR: In this article, the authors examined the conductor loss and effective dielectric constant of microshield lines and presented results on transitions to conventional coplanar waveguide, right-angle bends, different stub configurations, and lowpass and bandpass filters.
Abstract: Several millimeter-wave passive components have been fabricated using the microshield transmission line geometry, and their performance is presented herein. Microshield is a quasi-planar, half-shielded design which uses a thin dielectric membrane (1.5 /spl mu/m) to support the conducting lines. This approach provides a nearly homogeneous, air-filled environment and thus allows extremely broad-band TEM operation. This paper examines the conductor loss and effective dielectric constant of microshield lines and presents results on transitions to conventional coplanar waveguide, right-angle bends, different stub configurations, and lowpass and bandpass filters. Experimental data is provided along with numerical results derived from an integral equation method. The microshield line is shown to be very suitable for high performance millimeter and submillimeter-wave applications. >

153 citations


Journal ArticleDOI
TL;DR: In this paper, a coplanar waveguide design enabled uniform microwave power coupling to a five-segment array of 8192 junctions, so each segment had constant voltage steps over the same bias range.
Abstract: Series arrays of Nb–PdAu–Nb Josephson junctions were fabricated with characteristics ideally suited for application in programmable voltage standards and D/A converters with fundamental accuracy. Large arrays of junctions with applied microwave power showed constant voltage steps with current amplitudes as large as 7 mA. A novel coplanar waveguide design enabled uniform microwave power coupling to a five‐segment array of 8192 junctions, so each segment had constant voltage steps over the same bias range. The 8192‐junction device generated 1.1 mA steps at 186 mV with 11 GHz power and a maximum constant voltage step of 260 mV at 15.34 GHz.

129 citations


Journal ArticleDOI
TL;DR: In this paper, design guidelines for single and double folded-slot (DFS) antennas on a dielectric half-space are presented, and the resonant circumference and self-and mutual impedances of single folded-slots on various substrates are included.
Abstract: Design guidelines are presented for single and double folded-slot (DFS) antennas on a dielectric half-space. The DFS antenna consists of two folded-slot elements which are separated by a half-wavelength and are fed from one side using a coplanar waveguide transmission line. A space-domain integral equation technique, based on the free-space Green's function, has been used to compute the resonant circumference and self- and mutual impedances of single folded-slots on various substrates. In addition, the input impedance and radiation patterns of DFS designs are included. Specific examples are shown for air, quartz, and silicon substrates, and measured data for DFS antennas on air and silicon substrates is provided to validate the calculated results.

110 citations


Journal ArticleDOI
TL;DR: In this article, a closed form expression for the attenuation constant due to conductor loss of coplanar waveguide (CPW) structures was obtained for an arbitrarily shaped edge and any conductor thickness.
Abstract: In previous work, we used a matched asymptotic technique to investigate the fields near an edge of a finitely conducting strip with nonzero thickness. It was demonstrated that with this asymptotic solution of the fields, the power loss in the region local to the edge could be determined accurately. In this paper, we will show how the accurate representation of the power loss can be used to obtain a closed form expression for the attenuation constant due to conductor loss of coplanar waveguide (CPW) structures. This expression is valid for an arbitrarily shaped edge and any conductor thickness. Results obtained with this expression are compared to and closely agree with both experimental results and other techniques found in the literature. We also investigated conductors with different edge shapes (45/spl deg/ and 90/spl deg/ edges) to explore their effect on the attenuation constant (or loss) of CPW structures.

103 citations


Journal ArticleDOI
TL;DR: In this paper, superconducting YBa2Cu3O7−x (YBCO) and paraelectric SrTiO3 (STO) layers on LaAlO3 substrates were used for microwave transmission through the coplanar transmission line.
Abstract: We have prepared electrically tunable microwave resonators incorporating superconducting YBa2Cu3O7−x (YBCO) and paraelectric SrTiO3 (STO) layers on LaAlO3 substrates. The top YBCO layer for each sample was patterned into a 8 mm long coplanar transmission line with a 40 μm gap and a 20 μm center line width. The microwave transmission through the coplanar transmission line exhibits resonances corresponding to standing microwaves along the coplanar transmission line. These resonances are modulated by applying a bias voltage between the center line and the ground planes. Samples with a 0.5 μm thick (2 μm thick) bottom STO layer show, for a resonance at around 8 GHz (5 GHz), a frequency modulation of about 4% (24%) and a quality factor Q of about 200 (50) under 100 V bias at 80 K.

93 citations


Proceedings ArticleDOI
Bonkee Kim1, Beom-Kyu Ko1, Kwyro Lee1, Ji-Won Jeong, Kun-Sang Lee, Seong-Chan Kim 
10 Dec 1995
TL;DR: In this paper, a monolithic inductor and transmission line on Si substrate with very high Q factor, low insertion loss, and high resonant frequency, achieved by using very thick polyimide (10/spl mu/m) as dielectric material, and thick Al (4 /spl mu /m) metalization system.
Abstract: The monolithic inductors and transmission lines on Si substrate with very high Q factor, low insertion loss, and high resonant frequency, are achieved by using very thick polyimide (10 /spl mu/m) as dielectric material, and thick Al (4 /spl mu/m) metalization system. This structure is made on the finished conventional standard two layer metalization BiCMOS wafer. For 10 nH inductor, 6 GHz resonant frequency, maximum Q factor of 5.5 at 1.2 GHz, and 1.2 dB insertion loss at 3 GHz are obtained, which are very comparable to those available in GaAs MMIC, These inductors can be used as RF choke as well as matching element. Transmission lines are also fabricated using this technology. The S/sub 21/ of coplanar waveguide with 1 mm length is -0.2 dB at 4 GHz, and that of microstrip line is -0.3 dB. It is expected that, using these passive elements, Si RF IC can be designed up to several GHz with performance comparable to GaAs MMIC.

86 citations


Journal ArticleDOI
TL;DR: In this paper, a ridge-type coplanar waveguide (CPW) electrode and asymmetric Coplanar strip line (A-CPS) electrode structures were proposed for ultra-broadband LiNbO/sub 3/ optical modulators.
Abstract: This paper describes novel coplanar waveguide (CPW) electrode and asymmetric coplanar strip line (A-CPS) electrode structures, introducing ridged LiNbO/sub 3/ substrates and thicker electrodes, for ultra-broad-band LiNbO/sub 3/ optical modulators. The structures are designed here with quasistatic analysis using the finite-element method. Ridged-structures with CPW and A-CPS electrodes are shown to be able to reduce the driving-voltage below that of the conventional planar-type electrodes and are suitable for modulation of exceeding 100 GHz and driving voltage of far less than 4 V under an optical wavelength of 1.55 /spl mu/m and 50 /spl Omega/ characteristic-impedance system. The ridge-type CPW can provide a broader bandwidth characteristic with a relatively thinner buffer layer and thinner electrode than the ridge-type A-CPS and is easier to fabricate. The ridge-type LiNbO/sub 3/ modulators are consequently candidate devices for future ultra-high-speed optical fiber transmission systems. >

80 citations


Journal ArticleDOI
TL;DR: In this article, a ribbon-of-brick-wall design of the coplanar waveguide bandpass filter is proposed, which is built from cascading several sections of quarter wavelength open-end series stubs.
Abstract: This paper proposes a novel ribbon-of-brick-wall design of the coplanar waveguide bandpass filter which is built from cascading several sections of quarter wavelength open-end series stubs. The design originates from modeling the series stub as a system of two asymmetrically coupled transmission lines, which is then made equivalent to a basic filter element of admittance inverter. The relationship between the parameters of the coupled transmission lines and the admittance inverter is derived and the design charts are provided for the convenience of the designers. Systematic procedure is established to design the Chebyshev filter, which is also fabricated and measured. In addition, the quasistatic equivalent lumped circuit models of the discontinuities formed between two sections are evaluated and incorporated into the circuit simulation to get better prediction for the filter performance. The good agreement between simulation results and experimental data justifies the design procedure and validates the present analysis approach. >

79 citations


Journal ArticleDOI
TL;DR: In this paper, nonlinear transmission lines (NLTL's) fabricated with Schottky diodes on GaAs were used to electrically generate 3.7-V step functions that had a measured 10%-90% fall time of 0.68 ps.
Abstract: Nonlinear transmission lines (NLTL's) fabricated with Schottky diodes on GaAs were used to electrically generate 3.7-V step functions that had a measured 10%-90% fall time of 0.68 ps. These NLTL's were integrated on wafer with sampling circuits that had a measured 3-dB bandwidth of 725 GHz. Key to circuit performance are the use of low-loss, high-wave-velocity elevated coplanar waveguide transmission lines and the elimination of active device pad parasitics by contacting devices above the plane of the wafer. >

Journal ArticleDOI
TL;DR: In this paper, an analysis of conductor-backed aperture antennas with multilayered substrate is presented, where the printed antennas are fed by a coplanar waveguide and the theoretical approach taken is to develop an integral equation over the aperture region and apply Galerkin's procedure in the spectral domain.
Abstract: This paper presents an analysis of conductor-backed aperture antennas with multilayered substrate. These printed antennas are fed by a coplanar waveguide (CPW). The theoretical approach taken is to develop an integral equation over the aperture region and apply Galerkin's procedure in the spectral domain. The properties of printed antennas with a CPW feed are characterized. Numerical results include the scattering parameters, antenna pattern, and radiation efficiency. The reflection coefficient, input impedance, and far-field pattern are also compared with measurements and good agreement is observed. >

Journal ArticleDOI
TL;DR: In this article, a new MMIC compatible sensor that measures RF power transmitted over a 50 /spl Omega/ coplanar waveguide is presented, based on the thermoelectric effect in AlGaAs and GaAs/AlGaAs micromachining technology is used for realisation.
Abstract: A new MMIC compatible sensor that measures RF power transmitted over a 50 /spl Omega/ coplanar waveguide is presented. The sensor is based on the thermoelectric effect in AlGaAs and GaAs/AlGaAs micromachining technology is used for realisation. A sensitivity of 1.1 V/W has been achieved with a reflection coefficient of 0.1 at 10 GHz, by a first realisation.

Journal ArticleDOI
TL;DR: In this article, a full-wave algorithm is proposed to analyze thoroughly a 90/spl deg/ bend of coplanar waveguide (CPW) based on the mixed potential integral equation (MPIE) formulation, the equivalent magnetic current distribution on the apertures is solved by the moment method using overlapping rooftop basis functions and the Galerkln weighting procedure.
Abstract: A full-wave algorithm is proposed to analyze thoroughly a 90/spl deg/ bend of coplanar waveguide (CPW) Based on the mixed potential integral equation (MPIE) formulation, the equivalent magnetic current distribution on the apertures is solved by the moment method using overlapping rooftop basis functions and the Galerkln weighting procedure The matrix pencil approach is then utilized to do the de-embedding procedure and extract both the coplanar and slotline modes scattering off the asymmetric discontinuity Experiments are performed to measure the scattering parameters and the results verify the accuracy of the present algorithm The full 4/spl times/4 scattering matrix between these two modes is presented from which the occurrence of the mode conversion is investigated The mode conversion is noticed to become almost complete at certain frequencies, which may be useful in the design of CPW to coupled slotline transition >

Journal ArticleDOI
TL;DR: In this article, a moment method analysis of a microstrip antenna fed by an open-end coplanar waveguide is presented, where the surface electric current on the antenna is represented by the entire domain basis functions.
Abstract: A moment method analysis of a microstrip antenna fed by an open-end coplanar waveguide is presented. The surface electric current on the microstrip antenna is represented by the entire domain basis functions, while the surface magnetic currents in the open-end slot and in the slots of the coplanar waveguide near the open end are expanded by the subsectional roof-top basis functions. Some practical numerical aspects are carefully discussed, and a numerical device is introduced to reduce the computation time for the integrals involving roof-top basis functions and the spectral-domain Green's function. The solution accuracy is thus improved. Computed results for the reflection coefficients and input impedances are given and compared with measured values. Good agreement between theory and experiment is obtained. >

Patent
Kei Goto1, Takayuki Kato1
26 Jan 1995
Abstract: A semiconductor device includes a substrate having a microwave semiconductor element, a microwave transmission line disposed on the substrate and electrically connected to the microwave semiconductor element, and a waveguide terminal structure disposed in the substrate and connected to an end of an external waveguide, wherein an end of a signal conductor of the microwave transmission line is included in the waveguide terminal structure. Input and output of microwave signals between the semiconductor device and an external device are carried out simply by applying an end of the external waveguide to the waveguide terminal structure. As a result, even when the substrate of the semiconductor device warps, an input-output characteristic evaluation of the semiconductor device is carried out with high stability. Further, the microwave signals are transmitted from the external waveguide directly to the microwave transmission line on the substrate or from the microwave transmission line directly to the external waveguide, thereby reducing transmission loss of the microwave signals.

Proceedings ArticleDOI
16 May 1995
TL;DR: In this article, the difference between flip chip and wire bond technology is demonstrated, and the influence of a metallic lid on a coplanar waveguide structure is examined, where the flip chip version has a lower insertion loss of the flip-chip interconnections and the higher flexibility of mounting the MMICs directly on the back structure of the planar patch antenna, leading to reduced losses of the feedline.
Abstract: In this paper the difference between flip chip and wire bond technology is demonstrated. Test assemblies with coplanar waveguides have been attached in flip chip and wire bond technology and measured up to 75 GHz. Further, the influence of a metallic lid on a coplanar waveguide structure is examined. To compare flip chip and wire bond interconnections, 51 GHz frontends with GaAs devices in coplanar waveguide technology have been realized. In one frontend the low noise amplifier (LNA) is connected to a planar patch antenna by wire bonding and in a second one by flip chip attachment. RF evaluations show the clear advantage of the flip chip version due to the lower insertion loss of the flip chip interconnections and the higher flexibility of mounting the MMICs directly on the back structure of the planar patch antenna, leading to reduced losses of the feedline. >

Journal ArticleDOI
Xiang Zhang1, T. Miyoshi1
TL;DR: In this paper, a finite element method combined with conformal mapping (FEM-CM) for a quasi-static analysis of coplanar waveguides (CPW) was presented, and the optimum CPW structures for the use in the Ti:LiNbO/sub 3/ optical modulator were discussed in detail to realize optical-microwave phase velocity match and electrode-source characteristic impedance match.
Abstract: In this paper, we first present a novel finite element method combined with the conformal mapping (FEM-CM) for a quasi-static analysis of coplanar waveguides (CPW). Using this approach, the optimum CPW structures for the use in the Ti:LiNbO/sub 3/ optical modulator are discussed in detail to realize optical-microwave phase velocity match and electrode-source characteristic impedance match. Our numerical results reveal that both conditions can be satisfied simultaneously by introducing a SiO/sub 2/ buffer layer and thicker electrodes. The modulator efficiency with respect to the voltage-length product is also evaluated for the optimized structures. Finally, the design guidelines to the optimum CPW structure are presented. >

Journal ArticleDOI
TL;DR: In this article, a non-leaky coplanar (NLC) waveguide with conductor backing was proposed. But the leakage in the multilayered structure can be removed if the geometrical and material parameters of the structure are chosen appropriately.
Abstract: In this paper, we present a structure called a non-leaky coplanar (NLC) waveguide with conductor backing. It is a multilayered structure with two possible configurations. The spectral domain approach with a complex root searching procedure is used to investigate leakage phenomena. The simulation results confirm that the leakage in conductor-backed coplanar waveguide (CBCPW) occurs in the form of wave in the parallel plate waveguide with infinite width. The results show that the leakage in the multilayered structure can be removed if the geometrical and material parameters of the structure are chosen appropriately. Experiments were carried out to investigate the transmission of these structures. It was found that the resonance in the transmission of finite-width conductor-backed coplanar waveguide (FW-CBCPW) is caused by the energy leakage from the dominant CPW mode. The resonance is eliminated in the NLC waveguides. These NLC waveguides are feasible and practical in the uniplanar MMIC design due to their planar nature. >

Proceedings ArticleDOI
16 May 1995
TL;DR: In this paper, a CPW-type stub and filter configurations for compact microwave circuit design are presented, where the stubs can be shortened by a factor of three by folding the center conductor and thin-film overlay capacitors integrated across the stub sections.
Abstract: This paper presents new CPW-type stub and filter configurations which are useful approaches for compact microwave circuit design. It is shown that conventional open- and short-end quarter wavelength stubs can be shortened by a factor of three by folding the center conductor. Also, narrowband open-end stubs are demonstrated which have thin-film overlay capacitors integrated across the stub sections. In this work the circuits have been implemented using the microshield transmission line, a geometry in which a 1.4 /spl mu/m-thick dielectric membrane supports coplanar conducting lines virtually in free-space. The new stub configurations, however, are also suitable for standard substrate-supported CPW. >

Journal ArticleDOI
TL;DR: In this paper, a series of coplanar waveguide transmission lines in laser-deposited YBa/sub 2/Cu/sub 3/O/sub 7-/spl delta// and SrTiO/ sub 3/ thin films were fabricated to explore the electrical characteristics of monolithic microwave circuits with integrated high temperature superconductor and ferroelectric materials.
Abstract: To explore the electrical characteristics of monolithic microwave circuits with integrated high-temperature superconductor and ferroelectric materials, we fabricated a series of coplanar waveguide transmission lines in laser-deposited YBa/sub 2/Cu/sub 3/O/sub 7-/spl delta// and SrTiO/sub 3/ thin films. We characterized the voltage-tunable two-port microwave response of the transmission lines at cryogenic temperatures using a calibrated network analyzer system. Total phase shifts and phase tuning in these devices increased for increasing ferroelectric film thickness with only moderate increases in transmission loss. >

Journal ArticleDOI
TL;DR: In this article, an asymmetric coplanar waveguide with finite ground plane (ASYCPWFGP) was used to achieve a return loss better than 16 dB up to 50 GHz.
Abstract: A novel balun based on an asymmetric coplanar waveguide with finite ground plane (ASYCPWFGP) to coplanar strip (CPS) transition is presented. A return loss better than 16 dB is obtained up to 50 GHz. The baluns are combined with four silicon Schottky barrier crossover diodes to yield a planar double-balanced mixer (DBM) which demonstrates an ultra-broadband performance up to 40 GHz.

Journal ArticleDOI
TL;DR: In this paper, an undercut mesa and an air-bridged coplanar metal waveguide were used to reduce both the diode RC constant and the parasitic capacitance.
Abstract: We demonstrate a long-wavelength detector structure using an undercut mesa and an air-bridged coplanar metal waveguide to significantly reduce both the diode RC constant and the parasitic capacitance. Record electrical bandwidths of 120 GHz are demonstrated for long-wavelength photodetectors.

Journal ArticleDOI
TL;DR: In this article, the authors proposed a generalized scattering matrix method for full-wave analysis of the electromagnetic field also in the metallic regions, where the mode-matching method was revisited in the context of a network representation of discontinuities.
Abstract: Cascaded coplanar waveguide discontinuities with transverse dimensions of the order of some micrometers are analyzed by the mode-matching and generalized scattering matrix method. This approach permits a full-wave analysis of the electromagnetic field also in the metallic regions. Compared with full-wave analysis assuming perfect conductors and a subsequent loss computation based on the surface impedance model the accuracy is considerably enhanced. The mode-matching method is revisited in the context of a network representation of discontinuities. The implications of Tellegen's general network theorem on the mode-matching method, particularly on the testing functions, are investigated. Furthermore, the mode-matching method is related to the equivalence principle applied to discontinuities and to the continuity condition of voltage and current of quasi-TEM waves in the static approximation.

Journal ArticleDOI
TL;DR: In this paper, a new approach of modifying the conventional spectral-domain approach is proposed for an analysis of the coplanar waveguide whose signal strip and ground planes have finite thickness and conductivity.
Abstract: A new approach of modifying the conventional spectral-domain approach is proposed for an analysis of the coplanar waveguide whose signal strip and ground planes have finite thickness and conductivity. By introducing suitable equivalent sources in the slot and signal strip regions, the problem can be significantly simplified by reducing the two-dimensional numerical integration into the one-dimensional one, thus it can be treated as easily as the conventional spectral-domain approach. By this modified approach, both the phase constant and attenuation constant can be determined simultaneously without using the assumption that the metallization thickness is much larger or smaller than the skin depth. In this work, comparison with published theoretical and experimental results is presented to check the accuracy of the new approach's results. In particular, the effective dielectric constant /spl epsiv//sub eff/ and attenuation constant a of a coplanar waveguide with finite metallization thickness and finite conductivity are discussed in detail, together with the current distributions along the signal strip and ground planes. >

Patent
26 May 1995
TL;DR: In this article, a coaxial-to-coplanar-waveguide (C2C-WG) connector is proposed that incorporates a slabline section within the coaxial connector interface between a circular-coaxial-transmission-line-to coplanar waveguide transmission line.
Abstract: A coaxial-to-coplanar-waveguide connector that incorporates a slabline section within the coaxial connector interface between a circular-coaxial-transmission-line-to-coplanar-waveguide transmission line. As RF energy enters a circular coaxial input, the slabline section shapes the electromagnetic field distribution to more closely resemble that of coplanar waveguide at the output. The slabline section provides better field matching from the circular coaxial transmission line to the coplanar waveguide transmission line. Angular bends and lateral offsets can readily be incorporated in the connector.

Patent
25 Sep 1995
TL;DR: In this paper, a coplanar waveguide with an elongate waveguide signal conductor (48b, 48c) for each gate terminal (70) on the FET chip (26) is flip mounted on a connection region (32) of a substrate (30).
Abstract: A radio-frequency power amplifier (22) includes a multiple-FET chip (26) that is flip mounted on a connection region (32) of a substrate (30). An input impedance-matching network (62, 64) is also mounted on the substrate. The network includes a coplanar waveguide (24) having an elongate waveguide signal conductor (48b, 48c) for each gate terminal (70) on the FET chip (26) with a distal end (48d, 48c) spaced from the connection region (32) and a proximal end (48g, 48h) in the connection region. A capacitor (54, 56) couples each of the input signal conductor distal ends (48d, 48c) to an adjacent ground conductor (36, 38). The signal conductors (48b, 48c) and capacitors (54, 56) provide a selected impedance at a selected frequency. An output coplanar waveguide (28) includes, for each drain terminal (72) an output signal conductor (88) having an end (82a) in the connection region (32) that is electrically connected to the flip mounted FET chip (26). This waveguide (28) also has a length selected to provide desired impedance matching and may also have other means of impedance matching.

Journal ArticleDOI
TL;DR: In this paper, the authors studied voltage-tunable (0-200 V) broadband (0.1-5.1 GHz) microwave properties at room temperature and the liquid nitrogen temperature of two coplanar waveguide devices made from a Au / Sr 0.5Ba0.5TiO3 bilayer and a YBa2Cu3O7-x / SrTiO 3 bilayer, respectively.
Abstract: We have studied voltage-tunable (0–200 V) broadband (0.1–5.1 GHz) microwave properties at room temperature and the liquid nitrogen temperature of two coplanar waveguide devices made from a Au / Sr0.5Ba0.5TiO3 bilayer and a YBa2Cu3O7-x / SrTiO3 bilayer, respectively. The experimental results agree well with the predictions of simple quasistatic and quasi-TEM models. © 1995 John Wiley & Sons, Inc.

Journal ArticleDOI
TL;DR: In this article, the authors have developed and tested simple and inexpensive electronics for interfacing Rapid Single-Flux-Quantum (RSFQ) Josephson-junction circuits to room temperature digital systems.
Abstract: We have developed and tested simple and inexpensive electronics for interfacing Rapid Single-Flux-Quantum (RSFQ) Josephson-junction circuits to room temperature digital systems. Voltage-level (Non-Return-to-Zero) bit signals with a swing of /spl sim/150 uV, developed on-chip by standard SFQ/DC converters, and in some cases amplified to 1.5 mV swing by HUFFLE-type circuits, are passed to the 300 K environment using a high density (40 channel) flexible coplanar waveguide assembly. AC-coupled, 2-3 stage microwave Si-bipolar amps, and Emitter-Coupled-Logic (ECL) buffers accomplish voltage level translation to the standard ECL levels, Using this technique, data rates in excess of 1 Gb/s per channel can be achieved at low cost per channel,. >

Journal ArticleDOI
TL;DR: In this article, the authors applied the extended spectral domain analysis to analyze symmetrical and asymmetrical coplanar and non-leaky waveguide discontinuities, and derived the three-dimensional dyadic Green's function to calculate the contributions of horizontal (vertical) magnetic (electrical) currents.
Abstract: The extended spectral domain analysis is applied to analyze symmetrical and asymmetrical coplanar and non-leaky coplanar waveguide discontinuities. The three-dimensional dyadic Green's function is derived first to calculate the contributions of horizontal (vertical) magnetic (electrical) currents. No air-bridges are needed if the discontinuity is symmetrical, It is shown that the coupled slotline (CSL) mode excited by asymmetrical discontinuities drastically affects the CPW circuit performance. The effect of air-bridges used to suppress the unwanted CSL mode is studied. Experimental data agree very well with numerical results for CPW discontinuities. In addition, the discontinuities of a novel conductor-backed CPW structure, the non-leaky coplanar (NLC) waveguide, are also investigated. From experiment, it is found that the SMA-to-NLC transition causes power leakage. Except for the small leakage, theoretical and experimental results agree well.