Analysis and Design of a Substrate Integrated Waveguide (SIW) Cavity Slot Antenna for DSRC-Band Applications

This paper presents a substrate integrated waveguide (SIW) cavity slot antenna for the dedicated short-range communication (DSRC) band. The DSRC band (5.9 GHz) covers the vehicle-to-vehicle communication frequency range. Conductor-backed coplanar waveguide is used to feed the antenna. To ensure the improvement in the bandwidth, the out-of-band harmonics are suppressed by employing two quarter wave resonators and a shorting pin in the feed of the antenna. The antenna radiation characteristics are also improved by good impedance matching that is achieved by placing two between the radiating patches. The SIW concept implemented in the antenna is reducing the cross-polarization level and lateral leakage. The antenna is designed, fabricated, and measured to validate the design approach. The antenna achieves fractional bandwidth of 8.8%, with the gain of 7.45 dBi. Furthermore, the measurement also indicated the radiation efficiency of 88.68% and cross-polarization level below -33 dB.