Abstract: The present invention relates to a frequency-stable low-dielectric microwave dielectric ceramic material and a preparation method thereof. The material is prepared from the following components in percentage by mass: 70-90% of a main-phase ceramic material A, 10-30% of an auxiliary-phase ceramic material B and 0-1.0% of an oxide sintering aid C. The main-phase ceramic material A is MgxMeySiO2+x+y; the auxiliary-phase ceramic material B is composed of ?RO-bRe2O3-cTiO2, R is at least one of Ca or Sr, Re2O3 is at least two of Sm2O3, Nd2O3, Y2O3, Al2O3 and La2O3; and the oxide sintering aid C is at least one of MnO2, WO3 and CeO2.

Abstract: The disclosure relates to an ultra-wide passband five-order band-pass filter based on an LTCC process. The ultra-wide passband five-order band-pass filter comprises a ceramic substrate, a bottom input electrode, a bottom output electrode and a bottom grounding electrode. Five parallel resonators, a grounding polar plate, two series connection capacitors, two series connection inductors, a cross-coupling capacitor and a parallel inductor are arranged in the ceramic substrate; the two series connection capacitors comprise a first series capacitor and a second series capacitor; the two series connection inductors comprise a first series inductor and a second series inductor; and according to the filter, a five-order parallel resonance structure is adopted, out-of-band suppression is deepened through the five parallel resonance units, a cross coupling capacitor, a parallel inductor and two series connection inductors are innovatively introduced.