A Novel Wide-Band Butler Matrix for Vehicle Radars at 24GHz

Abstract

There is a great scientific and commercial interest in car radars for anti-crash and pre-crash systems, for which beamformer networks with antenna arrays are becoming the norm. In this paper a novel Butler matrix at 24 GHz using a new type of micromachined suspended transmission-line couplers presented. This configuration arranges all the couplers in the center so that no line crossovers are needed. This circuit has been micromachined on a glass-quartz substrate and BCB layers have been used to suspend the transmission lines of the coupler. In this paper the fabrication method will be fully described, simulated and preliminary experimental results are presented.