UWB circularly polarized coax-fed spiral slot antenna

A design of a circularly polarized (CP) coax-fed spiral slot antenna for ultra wide band (UWB) requests is offered. In the presented structure, an Archimedean spiral shaped radiating element is utilized to produce UWB CP functionality. In order to reducing the antenna size, number of spiral turns, and reflected energy, chip resistor is used to dissipate energy at the end of arm. Although by added spiral slotted ground plane, deforming at bottom of designed antenna, reflected energy is existed, and much wider bandwidth can be produced, especially at the lower bands. The proposed antenna radiates a bidirectional wave with opposite CP.