Developing Millimeter-Wave Planar Antenna With a Cosecant Squared Pattern

This communication reports a novel planar array antenna having a cosecant squared pattern for millimeter-wave communication systems. The substrate integrated waveguide, which has high quality factor, low transmission loss, and no parasitic radiation, has been adopted to develop the proposed antenna. To improve the design efficiency, the aggressive space mapping (ASM) algorithm is used for synthesizing the desired excitations with low computation cost and high accuracy. A radiation model that considers mutual couplings among element antennas is developed based on the active element pattern for the coarse model of the ASM. And the genetic algorithm is adopted for the parameter mapping and extraction of the ASM process. As a demonstration, a prototype has been designed with a center frequency of 42.6 GHz, and experiments are carried out to verify the design. The measured results show that the measured antenna has a cosecant squared region up to 40°, a gain of 17.7 dBi at 42.6 GHz, and the maximum sidelobe is lower than -16.5 dB. The proposed antenna can be used for the base station of the long-range Qlink-Pan communication system.