A 45 degrees slant polarized radar antenna is designed using gapwaveguide technology. Using slant polarization in radar antennas is beneficial for collision avoidance applications as interference from opposing radars can be reduced. With a curved distribution network, the design complexity of the radiation layer is low allowing for easy fabrication. The element design consists of 4 slanted slots and is implemented in an array resulting in a realized co-polarized gain of 17.18 dBi averaged over the 76-81 GHz frequency band, and can scan to +/- 50 degrees in the azimuth plane.