Miniaturised double-coaxial cavity resonator and duplexer with ZOR characteristic using air-core coils

A novel method of miniaturising the size of a coaxial cavity resonator by utilising zeroth-order resonance (ZOR) characteristics is presented. This miniaturisation has been achieved through the introduction of aircore coils inside a conventional coaxial cavity resonator. This structure possesses ZOR characteristics, which results in the miniaturisation of the resonator while still exhibiting a rea...