Near-field behavior from circular aperture antenna and tunable gain of a super-Gaussian beam

Abstract

Using the aperture field integral method, near-field behavior of a super-Gaussian beam from a circular aperture is presented. Some analyzing expressions of aperture antenna gain are obtained, both under the focusing condition and in unfocused cases. It has been demonstrated that under the focusing condition, the gain at focus of a circular aperture antenna varies evidently with super-Gaussian parameter m. For the unfocused case, the peak gain of an aperture antenna is achieved when m = 2. Furthermore, radiation patterns of an aperture antenna relate to the observing point position as well as the ratio of the aperture (RAW) to the beam waist. An important finding is that the gain of the aperture antenna can be tuned by varying m.

Keywords:

• near-field gain
• super-Gaussian distribution
• circular aperture antennas

Acknowledgements

We would like to appreciate the support from The Fundamental Research Funds for the Central Universities (G470216 and 2009RC0308) and Project 60802033, 60973111 and 60873190 supported by NSFC. Thanks also for the reviewers' valuable suggestions.