Compact and Low Cost Linear Antenna Array for Millimeter Wave Automotive Radar Applications

A low-cost microstrip patch antenna array is proposed in this paper for automotive radar applications in ISM 24 GHz band. The elements of the center-fed array are connected in series to make a compact design with low complexity by obviating Wilkinson power divider. This approach also helps to reduce the dielectric losses of the array. A full-wave electromagnetics (EM) software EMPIRE XPU is used in the design process. The measurement results show 25 percent fractional bandwidth in terms of antenna impedance (23.75–30 GHz), 8.5 dBi maximum gain, 6 degrees half power beam width (HPBW), -12 dB side lobe level (SLL), and more than 50 dB isolation between TX/RX in the desired frequency range.