Millimeter-Wave Planar Antenna Array for Radar and Sensing Applications

We propose an efficient high gain millimeter-wave planar antenna array. The packaging of the antenna array feeding structure is eliminated by aggregating the feeding network in between the antenna elements, which has a significant advantage in maintaining neat and symmetric radiation characteristics with low cross polarization level. The proposed antenna array is extremely low in cost and can be used as either a linearly or circularly polarized antenna array. The antenna array has a realized gain of 20 dBi in both scenarios. The matching bandwidth is 4.1% and the 3-dB axial ratio bandwidth is 6%. The antenna array only uses a single substrate layer with no need for any vias. To switch to circular polarization operation, a 3D printed dielectric polarizer is used. The proposed antenna array suits well various applications at 24 GHz, while maintaining high performance metrics, and extremely low cost. The antenna array can be easily integrated with transceivers due to the use of printed microstrip line technology.