Microstrip resonators having reduced radiation loss

The radiation loss of several forms of microstrip resonator is considered with a view to determining a form which retains as far as possible the advantages of compactness and easy fabrication of the half-wave o.c. resonator, but having reduced radiation loss. A new form of resonator, of U shape or `hair-pin¿ configuration, is proposed, and theoretical and experimental confirmation of its low radiation is described.