摘要:

The wave functions for propagation of rotationally symmetric modes in circular gyrotropic waveguides with azimuthal magnetisation (the complex Kummer and Tricomi confluent hypergeometric functions) are studied analytically and numerically. Based on specially compiled tables, families of curves are presented, illustrating the behaviour of both higher transcendental functions. The analysis allows a comprehensive treatment of closed and opened circular guiding structures with radially stratified gyrotropic layers, magnetised azimuthally.

DOI:10.1049/ip-h-2.1988.0026

出版商:IEE    

年代:1988

数据来源: IET

摘要:

A new algorithm for calculating the excitation coefficients of Dolph-Chebyshev arrays is based on reconstructing the Schelkunoff polynomial from its roots. The new method compares favourably with a number of others as regards speed of computation and/or sensitivity to the precision of the computer arithmetic employed.

DOI:10.1049/ip-h-2.1988.0027

出版商:IEE    

年代:1988

数据来源: IET

摘要:

Design and measured results for two X-band conformal microstrip arrays are presented. The two 4 × 4 arrays are built on the surface of a cylinder of small radius. They differ by the orientation of the elements relative to the cylinder axis. The measured directivities and radiation patterns are in reasonable agreement with theoretical predictions.

DOI:10.1049/ip-h-2.1988.0028

出版商:IEE    

年代:1988

数据来源: IET

摘要:

Numerical results are presented for impedance, near field, and far field, for a relatively large NEMP-simulator wire antenna in the frequency range 100 kHz to 100 MHz. The results were obtained by a program based, essentially, on the simultaneous Hallen-type equations of Kominami and Rokushima.

DOI:10.1049/ip-h-2.1988.0029

出版商:IEE    

年代:1988

数据来源: IET

摘要:

Taking advantages of the low loss and open nature of the groove guide, and of relatively cheap linear transducers, a simple technique has been developed to measure dielectric properties at 100 GHz using a groove-guide resonator. The change of frequency or length to restore resonance before and after the insertion of the dielectric and the change of the respective (Mactor can be used to compute both the permittivity and the losstangent of the dielectric.

DOI:10.1049/ip-h-2.1988.0030

出版商:IEE    

年代:1988

数据来源: IET

摘要:

Dual resonant modes in hollow cavities, and in dielectric resonators occur in degenerate pairs, having either identical, or very closely situated, resonant frequencies. Equivalent circuits for the input impedance of such dual-mode resonators are analysed and the behaviour of the impedance locus, typically observed with the vector network analyser, is described.

DOI:10.1049/ip-h-2.1988.0031

出版商:IEE    

年代:1988

数据来源: IET