Aspect Ratio: A Major Controlling Factor of Radiation Characteristics of Microstrip Antenna

Syed Md. Danish Abbas, Sharmistha Paul, Jhelam Sen, Prity Rani Gupta, Kaushik Malakar, Sudipta Chattopadhyay, Sandip Banerjee

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DOI: 10.4236/jemaa.2011.311072                

Abstract

The effect of aspect ratio (width-to-length ratio) on overall radiation characteristics of a rectangular microstrip patch antenna is theoretically investigated with a view to develop a concrete physical insight in to the phenomenon. The detailed variation of co polarized and cross polarized radiation performance as a function of aspect ratio is thoroughly presented. The gain enhancement of a microstrip patch antenna along with a radical variation of cross polarized field radiation with aspect ratio is obtained. Indeed the conjecture of occurring different fringing fields with different aspect ratio is employed to theoretically estimate the effective size of a rectangular patch, and hence to determine the quantitative change in the gain value. Close agreement amongst the theory and simulations justifies the conjecture indicating a concrete physical insight in to the fact. The aspect ratio for which the cross polarized field radiation is minimum for a particular patch is also presented and justified quantitatively.

Keywords

Aspect Ratio, Co-Polarized Gain, Cross Polarized Radiation, Microstrip Patch

Conflicts of Interest

The authors declare no conflicts of interest.

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