In this paper, we have presented simulated and measured results of tunable monopole circular microstrip antenna for wide frequency impedance bandwidth which covers low frequency wireless applications. The proposed antenna consists of two identical slots placed on either side of feed axis having fixed dimensions of L1=0.446 cm, L2= 0.6 cm and width W1= 0.4cm. A stub of fixed width is loaded on left side of patch having with Ws=0.9 cm .The upper and lower length of stub is varied from LUS=0.62 to 1.22 cm and LLS=0.457 to 1.057 cm to tune an antenna for wide frequency impedance bandwidth from 1.7425 GHz to 1.4725 GHz. This variation also increases the impedance bandwidth from 163 to 200%when simulated where as it varies from 98.6 to 164 % when measured and gives a peak gain of 1.9079 dB. The proposed antenna can cover all low frequency microwave applications like GPS, GSM, DCS, PCS, UMTE, LTE, Wi-Fi, WLAN, Wi-MAX, FCC ID etc., The simulated results are in good agreement with experimental results .The VSWR is less than 2. The radiation patterns are nearly Omni directional nature both in E and H plane.

Identical slots, stub, TMCMSAWB and FIBW

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