Circular Dipole Antenna for Mode 1 UWB RadioWith Integrated Balun Utilizing a Flex-Rigid Structure

摘要

Abstract—Afully integrated dipole antenna with balun for ultra-wideband (UWB) radio utilizing a flexible and rigid printed circuit board is presented in this paper. The concept in this paper is to take advantage of the respective possibilities of the rigid and flex-ible parts. The balun utilizes broadside-coupled microstrips and is integrated in the rigid part of the printed circuit board, whereas the radiator is placed in the flexible part. The antenna with thebalun covers the mode 1 UWB frequency-band 3.1–4.8 GHz (with margin) at voltage standing wave ratio (VSWR) < 2. Further-more, good radiation characteristics and a linear phase responseare observed with measurements.