High frequency performance and compact LTCC bandpass filter (BPF) with three transmission zeros

Abstract

In this paper, a design of compact LTCC bandpass filter with three layers and three Transmission Zeros (TZs) is proposed, which obtain a high skirt selectivity with narrow passband and wide stopband. The mixed Electric and Magnetic (EM) coupling and Source-Load (S-L) coupling are utilized to create TZs in this design. And the simulated results of the proposed filter are presented to validate, which show that the passband is 2.2GHz-2.6GHz with center frequency 2.4GHz. Due to the LTCC multilayer structures, the filter's size is 2.9 mm × 2.8 mm × 0.4 mm (0.064λ g × 0.062λ g × 0.009λ g ).