Accurate CAD formulation for rectangular microstrip patch antennas

CAD of mechanically tunable rectangular microstrip patch with variable aspect ratio

Abstract: An improved CAD formulation is proposed to determine accurate input impedance of rectangular microstrip patches with variable aspect ratio. This paper demonstrate the effect of aspect ratio of rectangular microstrip patch on its input impedance. The computed results have been verified with our own experiments and simulated data showing very close agreement amongst them.

Microstrip radiating structures: Theoretical and experimental investigations executed in recent years at the University of Calcutta

Abstract: In this paper, we have presented a comprehensive review of research on microstrip antennas conducted at the Institute of radio Physics and Electronics, University of Calcutta with an emphasis to those done in recent years.

An experimental investigation of electrically thick rectangular microstrip antennas

Abstract: The electromagnetic properties of electrically thick rectangular microstrip antennas were investigated experimentally. Antennas were fabricated with different patch sizes and with electrical thicknesses ranging from 0.03 to 0.23 wavelengths in the dielectric substrate. The resonant frequencies were measured and compared to existing formulas. The bandwidth was calculated as a function of electrical thickness and the antenna radiation patterns were measured.

Microstrip antennas on synthesized low dielectric-constant substrates

Abstract: Micromachining techniques using closely spaced holes have been used underneath a microstrip antenna on a high dielectric-constant substrate (/spl epsiv//sub r/=10.8) to synthesize a localized low dielectric-constant environment (/spl epsiv//sub r/=2.3). The measured radiation efficiency of a microstrip antenna on a micromachined 635-/spl mu/m thick /spl epsiv//sub r/=10.8 Duroid 6010 substrate increased from 48/spl plusmn/3% to 73/spl plusmn/3% at 12.8-13.0 GHz (including 3.3-cm feed line losses). We believe that this technique can be applied to millimeter-wave antennas (microstrip, dipoles, slots, etc.) on silicon and GaAs substrates to result in relatively wideband (3-6%) monolithic microwave integrated circuits (MMIC) active antenna modules for phased-arrays and collision-avoidance systems.

Resonant frequency of circular microstrip antennas with and without air gaps

Abstract: An improved analytical model is presented for calculating the resonant frequency of circular microstrip antennas with and without air gaps. Unlike the previous models, the present one is widely applicable to all patch diameters-from very large to very small compared to the height of the dielectric medium below the patch and also to the substrates covering the entire range of dielectric constants. The computed results for different antenna dimensions and modes of resonance are compared with the experimental values.

Design considerations for rectangular microstrip antenna elements with various substrate thicknesses

Abstract: The effective design and analysis of microstrip antennas presupposes the quantitative knowledge of the effects of the physical and mechanical properties of the patch, the ground plane, and the substrate material on electromagnetic properties of the antenna. The behavior of antenna electromagnetic properties for varying mechanical and physical properties of the patch, the ground plane, and the substrate material is presented. A set of graphs for a relevant set of parameters is presented which enables the designer to clearly see the tradeoffs involved in choosing specific parameters for the antenna. Several parameters that are deterrents to the proper functioning of the antennas are also identified. © 1998 John Wiley & Sons, Inc. Microwave Opt Technol Lett 19: 111–121, 1998.