Micromachined CPW-fed suspended patch antenna for 77 GHz automotive radar applications

A new approach to high performance patch antenna at millimeter wave, especially 77 GHz of frequency for automotive applications, is introduced. The proposed antenna is composed of coplanar waveguide (CPW) feed line, a feeding post, supporting posts, and a radiating patch. The performance of antenna was improved by elevating the radiating patch in the air while remaining feed network on the high dielectric constant substrate. A 2 /spl times/ 1 array antenna was also designed with a simple feed network. The fabricated antenna showed broadband characteristics and high radiation efficiency. Measured -10 dB bandwidths were about 9.0 GHz (11.8 %) from 73.3 GHz to 82.3 GHz in single patch antenna and about 10.0 GHz (12.7 %) from 73.9 GHz to 83.9 GHz in 2 /spl times/ 1 patch array antenna. Simulated radiation efficiencies were 94 % for single patch antenna and 93 % for 2 /spl times/ 1 patch array antenna respectively.