Design and Testing of a Microstrip Patch Antenna for Vehicle-to-Vehicle Communication

In this paper, a linearly polarized compact patch antenna for potential application to vehicle-to-vehicle communication is presented. This work focuses on the antenna's miniaturization for enhanced gain and wide half-power beamwidth. Two quarter-wavelength resonators are used as a part of the feeding network which leads to suppression of the unwanted out-of-band harmonics. As a result, the impedance bandwidth is slightly enhanced, and the patch size is also reduced by 25.4% as compared to the conventional patch. In addition, two semicircular slots are etched on radiating part in each direction to boast the symmetrical current distributions, thereby, enhancing the polarization purity of the antenna. Moreover, a circular slot is used at the center of the radiating patch to improve the proposed structure's front-to-back ratio. The antenna is fabricated and validated experimentally. The measured values of fractional impedance bandwidth of 4.0%, peak realized gain of 6.0 dBi, cross-polarization level of 40.7 dB, and front-to-back-lobe ratio of 20 dB is achieved at 5.9 GHz. Additionally, the simulated radiation efficiency of 95% is obtained. Such features are a potential for application to aerodynamic wireless devices in intelligent vehicles for blind spot detection.