Special Issues and Features of a Scanning Reflectarray Antenna Based on Ferroelectric Thin Film Phase Shifters

摘要

Thought there are examples of scanning phased array antennas that have flown successfully in space, the quest for "low-cost", high-efficiency, large aperture microwave phased arrays continues. The reflectarray promises greater efficiency and economy compared to directly-radiating varieties. Implementing a practical scanning version has proven elusive. The ferroelectric reflectarray, underdevelopment and described herein. involves phase shifters based on coupled microstrip patterned on Ba{sub}xSr{sub}(1-x)TiO{sub}3 films, that were laser ablated onto LaAlO{sub}3 substrates. These devices outperform their semiconductor counterparts from X-through and K-band frequencies. There are special issues associated with the implementation of a scanning reflectarray antenna, especially one realized with thin film ferroelectric phase shifters, This paper will discuss these issues which include: modulo 2π effects and phase shifter transient effects on bit error rate; scattering from the ground plane; relevance of phase shifter loss; presentation of a novel hybrid ferroelectric-semiconductor phase shifter; and the effect of mild radiation exposure on phase shifter performance.