New Antenna Materials and Technologies

Not Available The objective of SAL (silicon-carbide adjustable limiter) is to design a replacement limiter for the Cooperative Engagement Capability (CEC) transceiver upgrade. The SAL will withstand 250 W while occupying no more space than the present limiter. More than twice as much power has to be transferred to the heat sink through a limiter with the same foot print as the present CEC limiter. This will be accomplished by designing the limiter from silicon carbide (SiC). The high thermal conductivity and high operating temperature of SiC solves the heat-transfer problem. To avoid problems experienced by others using bipolar SiC devices, Mission Research Corporation will design the limiter with n-type field-effect transistors (FETs). A working prototype will be made with chip and wire technology and tested for feasibility. We have successfully performed this type of design in gallium arsenide (GAL) and are presently teamed with Raytheon to develop and market a commercial product. The SAL approach can be used to design compact limiters for any system. The flexibility of the FET circuit can be utilized to design limiters with adjustable insertion loss for avoiding pulsed interference; hence the acronym SAL for SiC Adjustable Limiter. Since the field-effect transistor is amenable to monolithic integrated circuit techniques, this work will set the stage for the production of integrated receiver front ends when SiC technology matures sufficiently to support low-noise amplifier design.