Quad-Band Diversity Antenna for Automotive Environment

A compact, unilateral grounded Coplanar Strip (CS) antenna for automotive communications is presented in this letter. The antenna is designed for quad band operation covering DCS1800, IEEE 802.11b/g/n standards, Wi-MAX, Vehicle-to-Vehicle (V2V), and Vehicle-to-Infrastructure (V2I) Communications. A simple folded microstrip line radiator along with unilateral ground plane of CS is attempted to generate the required frequency bands. To achieve polarization and pattern diversity functionality, a 4 port diversity antenna array is developed. The antenna unit cells are spaced 0.125λ_g1 calculated at the lowest resonant frequency and are oriented orthogonal to adjacent unit cells to achieve high isolation greater than 20 dB, correlation coefficient less than 0.25 and diversity gain greater than 9.5 dB. The proposed antenna is suitable for automotive communications as it can be conveniently placed anywhere inside the vehicle more specifically in the wind screen, side mirrors and fenders.