Investigation of Curvature Radius on the Performance of a Reconfigurable Microstrip Parasitic Array (RMPA)

This work studies the effects of curvature on a pattern reconfigurable microstrip parasitic array (RMPA). Varying the effective electrical length of the parasitic elements allows for switching or scanning the beam pattern. The RMPA is simulated on a singly curved surface and oriented to scan along elevation. The resonant frequency of the structure is observed to decrease with the radius of curvature. Additionally, beam tilting behavior significantly deteriorates relative to the planar design. Several design parameters are investigated for the purpose of correcting beam tilting performance, including substrate width and parasitic element length and spacing. As the curvature radius decreases, simulations indicate that smaller element spacing improves the directivity of the beam at higher frequencies.