High gain active microstrip antenna for 60-GHz WLAN/WPAN applications

A 60-GHz active microstrip antenna design comprising a three-stage pseudomorphic high electron mobility transistor amplifier integrated with a high gain antenna on an alumina substrate is presented. The amplifier has 18-dB gain and is ribbon bonded to the substrate on which the antenna is defined. The antenna is a microstrip array antenna with a simple etched pattern for producibility at high frequencies. Two antenna layouts are designed, for different coverage areas: a single array having 13.4-dBi directivity and a double array with 14.6-dBi directivity. Antenna losses are approximately 1-2 dB, giving antenna gains of about 12 and 13 dBi, respectively. Mechanical simplicity is achieved with this design, and unnecessary transitions are avoided. Measurements are performed on amplifier and antenna separately, as well as on the integrated design. Amplifier chips with and without benzocyclobutene passivation are fabricated and measured for comparison