A low profile reconfigurable antenna for defense aircrafts

Abstract

In this paper a low profile frequency reconfigurable antenna is proposed that can conform to the host surface. The proposed design is a pixelated antenna structure with a grid of small metallic patches with RF switches for re-configurability. The prototype of the proposed design is designed on an FR4 substrate with the relative dielectric constant of 4.4 and thickness of 1.6 mm. This antenna is capable of resonating in three different frequencies. The prototype resonates at 10 GHz with return loss of − 12.47 dB and gain of 4.35 dB, 3.9 GHz with return loss of − 19.95 dB and gain of 3.52 dB and 2.6 GHz with a return loss of − 14.22 dB and gain of 4.26 dB. The simulated result shows that the gain of the pixel antenna on FR4 substrate ~ 4 dB comparable to gain attained by pixel antenna on substrates with low tangent loss and low dielectric constant. It is observed that the measured results are in good agreement with the simulated result.

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