mmWave multibeam phased array antenna for 5G applications

A fully integrated 28 GHz, 5G mmWave microstrip phased array antenna on a multilayer substrate is presented. The proposed $ 8\times 8 $ 8×8 array provides independently steerable, simultaneous multiple beams in any arbitrary azimuth, elevation angles with equal or unequal peak gains. A computation method is proposed to calculate the weights required to generate multiple beams. Multiple beams (up to six) over various arbitrary angles are generated using the proposed method and the results are presented. The inherent amplitude and phase variations due to the hardware impairments are independently captured through simulation and measurements, and their impact on the performance of the phased array is analyzed. Measured results are compared with simulations for single, dual, and multiple beams over arbitrary angles. The phased array performance is measured and presented over $ {\pm }35^\circ $ ±35∘ and $ {\pm }25^\circ $ ±25∘ scan angles in azimuth and elevation planes respectively over 400 MHz bandwidth for both single and dual beam deployment. The proposed multibeam computation method is validated with measurements at 28 GHz for a dual beam case, ( $ \theta =25^\circ $ θ=25∘, $ \phi =0^\circ $ ϕ=0∘) and ( $ \theta =25^\circ $ θ=25∘, $ \phi =180^\circ $ ϕ=180∘) in azimuth plane for equal and unequal power beams with a side lobe level of better than 17 dB.