A Miniaturized and Low Insertion Loss LTCC Filter with Two Finite Transmission Zeros for Bluetooth Application

Abstract

This letter outlines the design and manufacture of a miniaturized bandpass filter realized by low-temperature cofired ceramic (LTCC) technology for bluetooth applications. The bandpass filter with a central frequency of 2450 MHz and a 100 MHz passband is designed as a three-dimensional (3-D) structure based on lumped components. Experimental measurements were compared with modeling. The insertion losses in the passband (100 MHz) were less than 1.2 dB and the attenuation was more than 20 dB in the stop band. The area occupied by the filter is 1.6×0.8×0.6 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> .