A D‐band wideband low‐cost array for antenna‐in‐package applications

A wideband patch array operating at D‐band for antenna‐in‐package applications is presented in this paper. The array consists of two symmetrically positioned subarray elements and a grounded coplane waveguide feed line. Four E‐shaped patches are loaded in the array to enhance bandwidth. All geometry of the array is manufactured on a single‐layer quartz substrate without via hole, so that the difficulty and cost of fabrication are relieved greatly. Good agreements of reflection coefficient, pattern, and gain between measured and simulated results are achieved. Measurement shows that the array exhibits a −10 dB bandwidth of 19 GHz from 138 to 157 GHz and a 3‐dB gain bandwidth covering 140–159 GHz with a peak gain of 11.8 dBi at 147 GHz. Properties of wideband, moderate gain, low cost, and easy manufacture are achieved in this array.