Circularly Polarized Patch Antenna Array at 24 GHz for Radar Applications

The paper presents the design of the novel circularly polarized antenna array operating at IMS band 24.05-24.25 GHz. The antenna array consists of 24 identical truncated patches which are serially fed through the microstip line. The antenna is a travelling-wave array with exponential power distribution which provides very good side lobe suppression of 32 dB in the whole operating band making it suitable for automotive radar applications. Simulated axial ratio is below 3dB in the range (24.07-24.27) GHz, the antenna gain is around 18 dBi, cross polarization is better than 15 dB and return loss is greater than 16 dB in the entire IMS band.