摘要:

AbstractMemory requirements often limit the scope of problems that can be solved using the finite‐difference—time‐domain (FDTD) method. However, problems involving complicated geometries with fine features and large geometries can be more readily handled using nonuniform orthogonal FDTD. Grid dispersion error on nonuniform meshes is addressed in this communication. The critical parameters of cell size in terms of wavelength and growth rate are studied. A theoretical analysis followed by a numerical example demonstrate that grid dispersion error can be held to acceptably small levels. © 1995 John Wiley&Son

ISSN:0895-2477    

DOI:10.1002/mop.4650100402

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

年代:1995

数据来源: WILEY

摘要:

AbstractAxially magnetized ferrite phase‐shift sections can be biased above or below ferrimagnetic resonance. Mode charts displayed in terms of frequency/bias field, rather than tensor entries, cater for partial magnetization. From this construction it is shown that TM modes have separate onset frequencies above and below ferrimagnetic resonance leading to unique modal hierarchies in each region. For one waveguide structure the theoretical cutoff numbers are compared with experimental data and the phase‐shift calculations are separately corroborated by finite‐element solutions. © 1995 John Wiley&Son

ISSN:0895-2477    

DOI:10.1002/mop.4650100403

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

年代:1995

数据来源: WILEY

摘要:

AbstractWe analyze and measure the electrical properties of a hybrid coplanar/ microstrip traveling‐wave optical modulator containing an InGaAs/InAlAs quantum‐well electron transfer structure. S‐parameter measurements to 20 GHz reveal the microwave refractive index and microwave loss as a function of waveguide geometry. These experiments allow us to project electro‐optical modulation bandwidths in excess of 40 GHz. © 1995 John Wiley&S

ISSN:0895-2477    

DOI:10.1002/mop.4650100404

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

年代:1995

数据来源: WILEY

摘要:

AbstractIn this work a numerical investigation is reported on the propagation regimes that allow single‐channel systems to obtain the maximum capacity in links with optical amplification. Links with anomalous and zero mean chromatic dispersion are considered, adopting both DS and stepindex fibers and operating at a wavelength of 1.55 μm. Solitons and NRZ signals are used. © 1995 John Wiley&Sons,

ISSN:0895-2477    

DOI:10.1002/mop.4650100405

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

年代:1995

数据来源: WILEY

摘要:

AbstractIn this article we present the analysis of an optoelectronic mixer (OEM) based on a metal‐semiconductor‐metal photodiode (MSM‐PD) in microwave fiber‐optic links. The nonlinearities inherent in the MSM‐PD OEM are examined by modeling its dc responsivity as a third‐order polynomial function of applied bias voltage. The OEM has been analyzed in terms of its conversion loss, carrier‐to‐noise ratio, and noise figure. © 1995 John

ISSN:0895-2477    

DOI:10.1002/mop.4650100406

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

年代:1995

数据来源: WILEY

摘要:

AbstractA systematic approach to the design of GaAs FET bandpass distributed amplifiers is presented for the first time. The graphical design procedures presented enable one to examine the trade‐offs between the design variables and arrive at the appropriate design for a specified gain and bandwidth. © 1995 John Wiley&Sons, I

ISSN:0895-2477    

DOI:10.1002/mop.4650100407

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

年代:1995

数据来源: WILEY

摘要:

AbstractA generalized calibration and de‐embedding technique for reflection‐based S‐parameter measurements of microwave devices is proposed. This technique allows two‐port calibration of a network analyzer directly from the embedded reflection coefficient measurements. This technique is a general one, in the sense that it can be implemented in network analyzers with or without transmission measurement capabilities. © 1995 John Wiley&S

ISSN:0895-2477    

DOI:10.1002/mop.4650100408

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

年代:1995

数据来源: WILEY

摘要:

AbstractHybrid modes in the broadside‐coupled coplanar waveguide (CPW) are examined for the first time using the full‐wave spectral‐domain method. Various numerical results for the characteristic impedances and effective dielectric constants are obtained to study the behaviors of the dominant and higher‐order modes as well as to assess the operating range of the dominant propagation modes in this structure. Criteria to enhance the dominant‐mode frequency range are also discussed. Over the dominant‐mode frequency range, the dispersion is low. However, variation of the characteristic impedances is more pronounced than that of the effective dielectric constants, indicating the need for dynamic characteristic impedances for accurate circuit designs. The results in the low‐frequency limit agree well with those obtained using a quasistatic approach. Also, the calculated effective dielectric constants of the dominant odd mode match closely the existing data for the effective dielectric constants of a shielded conductor‐backed CPW. © 1995 John

ISSN:0895-2477    

DOI:10.1002/mop.4650100409

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

年代:1995

数据来源: WILEY

摘要:

AbstractIn this Letter we propose a novel technique for all‐optical address recognition in all‐optical packet switching, based on wide‐deviation FSK with direct detection and FWM in semiconductor optical amplifiers. The probability of erroneous recognition is evaluated theoretically to assess the feasibility of this solution. © 1995 John Wiley&Son

ISSN:0895-2477    

DOI:10.1002/mop.4650100410

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

年代:1995

数据来源: WILEY

摘要:

AbstractA new method for analyzing a millimeter‐wave H‐plane waveguide Y‐junction circulator with a partial height ferrite post is presented. Simple formulas are developed for determining the center frequency of the circulator and the length of the ferrite rod. The lowest mode of operation is not unique and is dependent on the length of the ferrite post. Based on the newly derived formulas, several broadband 3‐mm circulators have been designed, assembled, and tested. Good agreement between the analytically obtained performance and experimental results is observed. © 1995 John Wiley&S

ISSN:0895-2477    

DOI:10.1002/mop.4650100411

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

年代:1995

数据来源: WILEY