Abstract
An omnidirectional circularly polarized (OCP) collinear helical antenna employing a form of self-canceling sections is proposed in this paper. It consists of three separateλ/2 (where λis the free space wavelength at the center frequency) helical sections, which serve as the radiating elements, and two λ/2 self-canceling sections to connect them. The self-canceling section is simply a wire folded in half to form two parallel sections with surface current directions opposing each other, thereby canceling out the far-field components. The current direction is reversed every half wavelength at the operating frequency. Thus, the surface current vector along the three helical wires would point in the same direction, achieving enhanced radiation. A prototype of the proposed antenna with a diameter of 0.12λand a height of 0.51λhas been fabricated and tested. Measured results demonstrate a maximum gain of 2.23 dBic, an axial ratio and impedance bandwidth of 15.8% and 2%, respectively.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
