SUPERCONDUCTING ANTENNAS - WHAT CAN THEY DO FOR THE NAVY

In situations where a limited platform size forces the use of electric ally small antennas (especially 30 Mhz-3 GHz), superconducting antenna s can increase gain performance by up to 10dB. Both superconducting el ectrically small half loops and spirals have shown significant increas es in performance over their normal metal counterparts. Additionally, compact arrays, such as a multi function array or GPS anti-jam arrays, where mutual coupling between elements increases loss can benefit fro m superconducting elements as well. Ongoing progress in the areas of h igh quality large area high temperature superconducting (HTS) thin fil m and multilayer growth, including frequency agile materials such as t he perovskite ferroelectrics, has opened the doors for producing super conducting antennas which could be used in the fleet. The development of cost effective small cryogenic coolers has also made superconductin g antennas a viable technology. This paper will review both the fundam ental RF properties of high temperature superconductors (HTS) and demo nstrations of increased performance by superconducting antennas. Condi tions requiring a superconducting antenna, examples of possible system s and industry's ability to produce them will be discussed. Supercondu ctivity is a viable technology ready for incorporation into appropriat e Naval RF systems.