Prospects for design and construction development of integral circuits of LC–filters based on the modern dielectric materials

Abstract

An analysis of design and technological solutions related to the production of integrated microwave filters based on modern materials - liquid-crystalline polymers (LCP) and low-temperature ceramics (LTCC) is considered. An important factor in the design of integrated filters based on multilayer printed circuit boards is the limited choice of designs for inductive and capacitive elements. It is proposed to use dielectric materials with more stable parameters and a wide range of operating frequencies (LCP up to 20 GHz, and LTCC up to 40 GHz). The results of comparison of the manufacturing process of microwave filters based on LCP and LTCC technologies are shown. One of the possible schemes and designs of a bandpass filter with a cut-off frequency of 2.9 GHz, a bandwidth of 500 MHz, and an insertion loss of about 1 dB is demonstrated. Experimental characteristics based on computer simulation of the microwave filter are presented. It is concluded that the use of LTCC-technology is preferable for solving the problem of microminiaturization of microwave filters, and the use of LCP-technology is expedient for creating narrower-band filters intended for operation in a higher frequency range of microwave filters.