摘要:

AbstractAn analysis of the relationship between complex permittivity and complex resonance frequency is proposed for a cylindrical cavity oscillating in a TM0mpmode. Effects of wall conductivity, coupling loops, and holes for the insertion of dielectric samples are fully taken into account. With dielectric samples of small radii, insertion holes produce the most important corrections. Their effect is modelled through a finite difference solution of the field equations in the neighbourhood of the holes. A computer program is described for the analysis, the use of which is illustrated with results of measurements.

ISSN:0894-3370    

DOI:10.1002/jnm.1660040403

出版商:John Wiley&Sons, Ltd    

年代:1991

数据来源: WILEY

摘要:

AbstractA moment method solution is presented to compute electromagnetic scattering from material bodies. The bodies are supposed to be homogeneous, arbitrarily shaped and lossy; they can be coated with very thin perfect conductors in some parts. A formulation of the scattering problem is made in terms of the equivalent surface current densities for which mixed potentials are used. The equivalent currents are expanded in the space‐domain by a triangular expansion function on the triangulated surfaces of the scatterer. The Galerkin procedure is carried out to test boundary integral equations and reduce the functional form of the equations to a partitioned matrix equation. The solution is applied to the scattering problem of a dielectric slab, a thin conductor coated by absorber material and a rectangular patch on a grounded dielectric slab. The computed backscattering radar cross‐section and surface current densities of the structures are presented and some of the results are compared with experimental d

ISSN:0894-3370    

DOI:10.1002/jnm.1660040404

出版商:John Wiley&Sons, Ltd    

年代:1991

数据来源: WILEY

摘要:

AbstractA new GaAs carrier transport modelling methodology is presented, designed to address the competing needs of microscopic detail and of computational efficiency. The rationale for advanced semiclassical models based on the Boltzmann transport equation (BTE) are reviewed and discussed in terms of the unique properties of GaAs. A new methodology is then presented, formulated around a one‐dimensional velocity–space variable. It includes a realistic description of the GaAs band structure including multiple valleys, non‐parabolicity, and anisotropy, which is used to explicitly evaluate the scattering distributions, and rates, for different scattering mechanisms. These in turn allow a direct evaluation of the BTE scattering inegral, which is solved iteratively with the non‐scattering terms. Based on this methodology, a prototype model is shown to reproduce the GaAs velocity–field relationship in homogeneous, undoped material. Band structure and forward‐scattering effects are clearly visible in the model's solutions for the carrier velocity distribution. The model's computational simplicity, combined with a finer level of detail, makes it suitable for device simulation without invoking Monte Carlo or other computationally intens

ISSN:0894-3370    

DOI:10.1002/jnm.1660040405

出版商:John Wiley&Sons, Ltd    

年代:1991

数据来源: WILEY

摘要:

AbstractThe relationship between microwave power absorbed by a detector diode and the resulting detected voltage at high signal level is investigated. Experimental data is obtained from a zero‐biased diode mounted in a rectangular waveguide system operating at 9.5 GHz. The Alpa Industries Inc. 4561, 6724 and 6725 Schottky diodes and the M/A‐COM 1N23 Point Contact diode with 1 kω and 106 kω loads are examined. TheP–Vrelationships are analysed by solving a system of non‐linear differential equations based on a lumped parameter model of the microwave system

ISSN:0894-3370    

DOI:10.1002/jnm.1660040406

出版商:John Wiley&Sons, Ltd    

年代:1991

数据来源: WILEY

ISSN:0894-3370    

DOI:10.1002/jnm.1660040402

出版商:John Wiley&Sons, Ltd    

年代:1991

数据来源: WILEY