摘要:

AbstractWe report a technique for measuring the spatial profile of microwave‐frequency currents in resonant thin‐film superconducting microstrip devices operated near resonance. We probe the patterned superconducting device as a function of position by scanning a modulated light beam across the region to be probed. With the light focused to a spot size much smaller than the microstrip width, we have measured the current density distribution as a function of position across the width of the strip. Using an elementary model for the superconducting current density distribution, we fit an effective penetration depth at the edge of the microstrip. © 1993 John Wiley&Sons,

ISSN:0895-2477    

DOI:10.1002/mop.4650061303

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1993

数据来源: WILEY

摘要:

AbstractA 3‐GHz‐bandwidth real‐time spectral‐analysis receiver has been demonstrated. The fully integrated compressive receiver is based on the chirp‐transform algorithm and uses a high‐Tcsuperconductive (HTS) tapped‐delay‐line chirp filter with a time‐bandwidth product of 40. The 3‐GHz bandwidth of the HTS chirp filter is unobtainable using other technologies such as surface acoustic waves. This prototype receiver, a combination of an HTS passive microwave component and conventional semiconductor circuits, demonstrates a microwave system that could not be built without the unique HTS component. © 1993

ISSN:0895-2477    

DOI:10.1002/mop.4650061304

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1993

数据来源: WILEY

摘要:

AbstractThe electrical parameters of III‐V semiconductor devices were measured at cryogenic temperatures. These data were used for the accurate design of high‐temperature superconductor (HTS)III‐V hybrid microwave circuits. A number of such hybrid circuits, including amplifiers, oscillators, balanced mixers, and a dual channel receiver front end were designed and fabricated. Some of the test data for these circuits are presented. © 1993 John Wiley&Son

ISSN:0895-2477    

DOI:10.1002/mop.4650061305

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1993

数据来源: WILEY

摘要:

AbstractApplications of HTS to radiating elements and beam‐forming networks of multibeam and/or multifrequency arrays are discussed. This includes radiating elements which meet special requirements with respect to size and frequency response. Realized versions of both a three‐port HTS array and a April × 4 Butler matrix are presented. © 1993 John Wiley&Sons

ISSN:0895-2477    

DOI:10.1002/mop.4650061306

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1993

数据来源: WILEY

摘要:

AbstractA method for characterizing the noise and conversion loss performance of high‐temperature superconductor (HTS) nonlinear components is described. Data on conversion loss and noise figure for step edge junctions (SEJs) manufactured on HTS is presented and discussed. © 1993 John Wiley&Sons, I

ISSN:0895-2477    

DOI:10.1002/mop.4650061307

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1993

数据来源: WILEY

摘要:

AbstractExperiments are performed on an HTS transmission line fabricated with a series array of Josephson junctions. We have determined the phase shift mechanism and have measured the magnitude of the phase shift of wide junctions. A qualitative model of the phase shift mechanism has been developed which explains the effects of applied magnetic fields. © 1993 John Wiley&Sons, Inc

ISSN:0895-2477    

DOI:10.1002/mop.4650061308

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1993

数据来源: WILEY

摘要:

AbstractThe performance of 7.3‐GHz two‐pole bandpass filters (5% bandwidth) fabricated on double‐sided Y‐Ba‐Cu‐O and Tl‐Ba‐Ca‐Cu‐O thin films deposited on LaAlO3is discussed. At 77 K, the Tl‐Ba‐Ca‐Cu‐O and Y‐Ba‐Cu‐O superconducting filters exhibited minimum passband insertion losses of 0.3 and 1.2 dB, respectively. An insertion loss of 3.4 dB was measured for an all‐gold filter a

ISSN:0895-2477    

DOI:10.1002/mop.4650061309

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1993

数据来源: WILEY

摘要:

AbstractHigh‐Q transmission high‐Tcsuperconducting coplanar waveguide resonators have been employed to make accurate measurements of the temperature dependence of the penetration depth via the change in phase velocity. Resonators made from several different film thicknesses are well described using a zero temperature penetration depth and a T‐squared temperature dependence using a full‐wave spectral‐domain model of the coplanar waveguide transmission line. © 1993 John Wiley

ISSN:0895-2477    

DOI:10.1002/mop.4650061310

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1993

数据来源: WILEY

摘要:

AbstractThe first fully integrated HTS millimeter‐wave oscillator operating at 77 K with a phase noise improvement of 20 dB over conventional oscillators is reported. A loaded Q of 59,000 at 36.5 GHz obtained from a sapphire resonator shielded by HTS ground planes is almost 100 times greater than ceramic resonators. © 1993 John Wiley&Sons, I

ISSN:0895-2477    

DOI:10.1002/mop.4650061311

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1993

数据来源: WILEY

摘要:

AbstractThe fundamental radiation characteristics of a microstrip antenna on a cylindrical substrate with a thick cover layer is investigated by using a magnetic line source model. Numerical results for the radiation pattern and conductance are presented. It is found that certain combinations of curvature radius and cover‐layer thickness could result in significant distortions in the pattern. Lossy dielectric material may be used to reduce these undesired effects. © 1993 John Wiley&Sons, I

ISSN:0895-2477    

DOI:10.1002/mop.4650061312

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1993

数据来源: WILEY