Design of a 77GHz Microstrip Antenna with Electrically Large Property

In this paper, a 77GHz microstrip antenna with electrical large property (ELP) is designed and simulated by high-frequency simulation software HFSS. We obtain the ELP antenna by cutting a gap in the middle of the rectangular antenna to construct the interdigital capacitor. The theory of the ELP antenna is analyzed by the surface current distribution and the electric field distribution of it. Compared with the traditional rectangular antenna, the dimensional area of the antenna is increased by 2.245 times, and the antenna maintains a good radiation pattern. The parameters of the antenna which affect the electrically large characteristics are discussed. From the results, we can see that this antenna can better adjust the impedance matching than the traditional antenna.