A Single-layer Series-fed Microstrip Array with Enhanced Bandwidth for Automotive Radar Systems

A series-fed antenna array is designed on a single-layer substrate with enhanced bandwidth to provide a cost-effective solution for automotive radar systems. Coplanar coupled feed is used to enhance the impedance bandwidth of a conventional rectangular patch. Differential feed technique is applied to cancel the inherent directional offset of the radiating patches. And the feed network is designed based on the Taylor distribution of the current to obtain low side lobe. The simulation results show that the proposed array exhibits an impedance bandwidth of 1180 MHz ranging from 23.6 GHz to 24.78 GHz. The gain is better than 15.5 dBi in bandwidth, and the side lobe level is lower than −23 dB.