In this paper a microstrip antenna on a suspended substrate with capacitive feed is presented. capacitive feed is created by a slot within the rectangular patch around the feed point. The proposed antenna exhibits a much higher impedance bandwidth of about 47% (S11 < −10 dB). Effects of key design parameters such as the air gap between the substrate and the ground plane, the gap width between r...

This paper presents an E-ring shaped printed monopole antenna for UWB applications with dual notched bands performance. In order to generate single frequency band notch function, we applied a U-ring shaped monopole antenna, and by inserting a rectangular ring in the centre of it an E-ring shaped radiating patch created and a dual band-notch function can be achieved. The measured bandwidth of th...

Energy beamforming (EB) is a key technique to significantly enhance the efficiency of wireless power transfer (WPT). In this paper, we study optimal EB under per-antenna power constraint (PAC) which is more practical than conventional sum-power constraint (SPC) at multi antenna energy transmitter (ET). We consider a broadcast network, where one multi antenna ET with PAC, transfers wireless ener...

The thesis describes a method of' beam steering aimed at producing a useful amount of deflection of an antenna beam from boresight, by a simple and Inexpensive method. For large antennas, It is difficult, as well as expensive, to steer the beam by more than a few beamwidths. The method studied was developed with particular reference to the beam steering requirements of Direct Broadcast Satellit...

The indirect two-port reflection method for measuring antenna impedances is reviewed using scattering parameter techniques and developed into a more accurate low perturbation optically coupled transmission measurement. This transmission measurement infers the antenna impedance by measuring the voltage induced in a number of loads connected to the antenna port with reference to the antenna used ...

fresnel zone plate antenna (fzpa) was considered as a recieving antenna. an expression of electric field on axis of antenna produced by an incidente plane wave was found . the expression was used for calculation of gain, efficiency and optimum phase correcting function. several fzpa are fabricated and tested. experimental and theoretical results were compared and it was shown that there was a g...