A Low-Cost Antenna Using SISL Technology With Suppressed Sidelobe Level for 77 GHz Automotive Radar

The letter proposes a substrate integrated suspended line low-cost antenna with suppressed sidelobe levels for 77 GHz automotive radar. The antenna consists of two embedded air cavities. The double-layer wiring with dielectric excavation makes more electromagnetic energy distributed in the air cavity, significantly reducing the dielectric loss. The sidelobe level is decreased to −15 dB according to the Chebyshev synthesis. The measured results validate that the antenna bandwidth is from 75.01–82.12 GHz which can cover the 77 GHz application (76–81 GHz) with the max realized gain of 13.5 dBi. In addition, the antenna is fabricated on the FR4 substrates resulting in low cost.