LTCC based electronically tunable multilayer microstrip-stripline combline filter

An embodiment of the present invention provides an apparatus, comprising a multilayer filter including a first resonator on a first layer of dielectric material or low-temperature-co fired-ceramic, a second resonator coupled to the first resonator on a second layer of dielectric material or low-temperature-co fired-ceramic, a third resonator coupled to the second resonator and cross coupled to the first resonator, and wherein a voltage tunable dielectric capacitor is connected to at least one of the resonators to electrically tune the multilayer filter.