Radiation efficiency measurement of a balanced miniature IFA-inspired circular antenna using a differential Wheeler cap setup

This paper presents the radiation efficiency measurement of a novel balanced miniature IFA-inspired circularly folded antenna whose maximum dimension is λ/14 at 433 MHz. The measurement is performed using a Wheeler cap (WCap) and a differential measurement setup using two feeding coaxial cables. Original narrowband WCap method is compared to the Ultra Wide Band (UWB) WCap approach. The accuracy of the measurement is discussed and additional simulations are performed to understand the overestimated results measured by the WCap method.