Implementation of a Compact EMI Filter Array for 4G-LTE Applications on LTCC

Abstract

In this paper, a mixed type material is described for the first time whereby a fully integrated electromagnetic interference (EMI) filter array in low-temperature co-fired ceramic technology is implemented. To miniaturize the size of the component and have high rejection and low insertion loss, a mixed powder material with a higher permittivity and a lower loss tangent is employed to design and fabricate the filter. The material system used in this paper is BaNd 2 Ti 4 O 12 + Ni-Cu-Zn ferrite. The addition of Bi 2 O 3 reduces the sintering temperature to below 900°C. A compact EMI filter array architecture that has a wide rejection band and sufficient isolation is also introduced. For the development of wireless communications, the spectrum for global 4G-Long Term Evolution (LTE) covers different frequencies within 700-2600 MHz. In this paper, an EMI filter array that rejects unwanted frequencies from 700 to 2700 MHz, which covers all 4G-LTE bands, is presented. The EMI filter array is 1.6 mm (L) × 0.8 mm (W ) × 0.5 mm (H), the smallest reported so far. The measured results of the developed filter are in good agreement with the simulated results by a fullwave electromagnetic simulator.

High attenuation electromagnetic interface filter for effective processing of audio signals

“…The following are some of the major problems that EMI can cause in the industrial sector. EMI can even more severely affect mission-critical functions in the military and medical fields [2]. A strong electromagnetic wave can induce unwanted electric currents in an electronic device, causing unintended operations or interfering with intended operations.…”