Design and Fabrication of Low-Loss Toroidal Air-Core Inductors

The design and fabrication of high-Q air-core toroidal inductors are described. Designs are optimized for maximum Q for a given size and inductance, independent any particular fabrication process. A fabrication process using a combination of thin-film processes and conventional machining has been used to make prototypes. Measurements performed on the first prototypes confirm the predicted Q of 115 at 50 MHz.

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