Status of ferrite technology in the United States

There has been steady progress in advancing the state-of-the-art in ferrite devices in the United States over the past several years. Microstrip circulator technology at microwave frequencies has advanced to the point where cost and manufacturability rather than performance are the major issues. A primary goal is to produce a ferrite device which is compatible in size and cost with monolithic microwave circuits. Activity in thin-film YIG filter technology has been waning in the United States over the past few years but the intrinsically high Q of YIG resonators and the compatibility of film technology with monolithic circuits may reverse this trend. Vacuum electronics will continue to play an important role in future military systems. There is currently a substantial triservice initiative to advance this technology along many fronts (microwave power modules, vacuum microelectronics, millimeter-wave amplifiers, crossed field devices, etc.) in support of military requirements.<>