Microwave devices utilizing magnetoelectric hexaferrite materials for emerging communication systems

Abstract

Ferrite materials are widely used in passive and tunable electromagnetic signal processing devices such as phase shifters, circulators, isolators, and filters. These materials can also be used as tunable antenna substrates and EMI suppression cores. Due to their excellent dielectric properties, ferrites possess the advantages of low loss and high power handling relative to semiconductors. Typically, parameters of magnetic materials are controlled by an external magnetic field thus allowing for tuning of device performance. Magnetic fields are usually generated using permanent magnets or current driven coils, leading to relatively large component size, weight, and cost, as well as slow response time in comparison to semiconductor-based technologies. Magneto-electric materials can be a practical solution to control the magnetic parameters of ferrites by electric field and/or voltage and would eliminate permanent magnets and tuning coils to overcome most of the disadvantages in the use of ferrites for microwave devices. A situation where ferrites are compatible with active components based on semiconductors would become a reality. Furthermore, key advantages of ferrites, including low insertion loss and high power handling capability could be exploited without the penalty of added size, weight, and cost, as well as increased response time.