Single-layer slotted post-wall waveguide array with compact feed-line structures for 77 GHz automotive radar

A single-layer antenna composed of four subarrays and compact low-loss feed-line structures connecting to an RFmodule for 77 GHz automotive radar systems is presented. This antenna is based on a slotted post-wall waveguide array, which is integrated in a ceramic-filled PTFE substrate. The antenna gain is higher than 16 dBi relative to the maximum available directivity of 20.4 dBi at 76.5 GHz. The proposed compact feedline structures achieve the low transmission loss of less than 3.2 dB.