Optimized Microstrip Antenna Arrays for Emerging Millimeter-Wave Wireless Applications

Two compact planar antennas operating in the unlicensed 60 GHz frequency band are presented based on the physical layer specifications of IEEE 802.15.3c and ECMA 387 standards for different classes of wireless applications. Each antenna is an array of 2 × 2 microstrip antennas covering at least two channels of the 60 GHz spectrum. The first antenna is optimized to achieve the highest gain, while the second antenna is optimized to give the largest beamwidth. The maximum measured radiation gain of the first antenna is 13.2 dBi. The measured beamwidth and gain of the second antenna are 76^° and 10.3 dBi, respectively. The areas of these two antenna are only 0.25 and 0.16 cm². The variation of radiation gain of each antenna over the frequency range of 57-65 GHz is less than 1 dB.