ULTRA WIDE BAND PLANAR PRINTED QUASI-YAGI ANTENNA WITH SIZE REDUCTION FOR WATER DETECTION IN THE EGYPTIAN DESERT

Ultrawideband quasi-Yagi antenna with size reduction is presented for developing the ground penetrating radar system. The proposed antenna printed on FR-4 substrate and consists of meandered driver dipole, a radial quarter-wavelength stubs, and two meandered parasitic strips. The meandered driver dipole is connected to the slot line through coplanar strip line. The ground plane is modified by symmetrically adding two extended folded meandered stubs to reduce the lateral size. The results show that the proposed quasi-Yagi antenna has a wide bandwidth and good unidirectional radiation characteristics. The -10 dB impedance bandwidth extends from 47 to 150 MHz with 45% size reduction and average gain around 4.5 dBi over operating band with very flat gain (around 5 dB) over the entire bandwidth. The proposed antenna presents an excellent end-fire radiation with a front-to-back ratio greater than 10 dB. Simulations and measurements show very good agreement with the proposed antenna. High frequency structure simulator is used to design and study the effect of sandy soil, water layer and the distance between sand and proposed antenna. (c) 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:226-233, 2015