Embedded Bandpass Filter Research Articles

Implementation of High-Q Embedded Band Pass Filter in Wireless Communication

At 12.8 MHz center frequency, the advanced miniaturized polymer-based planar high quality factor (Q) passive elements embedded bandpass filter works in the L-band. Because most of the demands operate inside the spectrum, the wideband or high-speed operation necessary to enhance must be acquired in microwave frequency ranges. The channel has a quiet, high-performance microfilter with wideband rejection. Capacitors and inductors are used in the high quality factor (Q) passive components, and related networks are incorporated in the filter. Embedded layers are concatenated using Three-Dimensional Integrated Circuit (3D-IC) integration, parasitics are removed, and interconnection losses are negotiated using de-embedding methods. A wireless application-based Liquid Crystalline Polymer (LCP) viewpoint is employed as a substrate material in this work. The polymer processes, their properties, and the incorporated high-Q Band Pass Filter Framework. The suggested filter model is computed and manufactured utilizing the L-band frequency spectrum, decreasing total physical length by 31% while increasing bandwidth by 45%.

Ultra-Compact WiMAX Bandpass Filter Embedded Into a Printed Circuit Board With a ${\rm SrTiO}_{3}$ Composite Layer

An ultra-compact bandpass filter has been developed for 2.3-2.7 GHz worldwide interoperability used for microwave access applications. The proposed filter was fully embedded into a multilayered printed circuit board (PCB) with a high dielectric strontium titanate (SrTiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> ) composite film layer. In order to reduce the size of the filter and to avoid unwanted 3-D electromagnetic coupling between the embedded passive filter circuit elements, the proposed filter was designed using J-inverter transformation technology. Two grounding via inductors and a single grounding capacitor were also utilized to generate three independent finite transmission zeros to enhance the rejection characteristics at the proper frequency bands. Since the J-inverter transformed filter circuit elements could be designed with relatively small inductance and large capacitance values, the high dielectric composite film was highly effective in reducing the size and improving the performance of the filter. The high dielectric film exhibited a dielectric constant of 17, a tangent loss of 0.01, and a capacitance density of 12.2 pF/mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> at 1 GHz. The measured maximum insertion loss in the passband ranged from 2.3 to 2.7 GHz was better than 1.8 dB, with a minimum value of 1.58 dB at 2.6 GHz. The return loss was higher than 15 dB in the passband. The transmission zeros occurred at 1.71 and 5.1 GHz, and provided suppressions of 45 dB at 1.71 GHz, and 54 dB at 5.1 GHz, respectively. The measured group delay was less than 0.8 ns in the passband. The embedded bandpass filter had a volume of 2.6 × 2.6 × 0.55 (H) mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> , which is the smallest one found, compared to previously reported devices, the filter, embedded into the eight-layered packaging substrate with the high dielectric composite layer, dramatically reduced the size up to 56%, and its performance was also much improved in comparison to the one embedded into a conventional six- layered PCB.

A Low‐Loss Fully Embedded Stripline Parallel Coupled BPF for Applications using the 60 GHz Band

This article presents a low‐loss fully embedded bandpass filter (BPF) using low‐temperature co‐fired ceramic (LTCC) for multilayer System‐in‐Package (SiP) and Multi‐Chip‐Module (MCM) applications, for example, wireless applications for the unlicensed 60 GHz band. Critical coupling gaps of conventional bandpass filters in this frequency range, which are not suitable for screen printing, could be eased by introducing coupling plates in adjacent layers. The four‐layer BPF is designed for Du Pont's 9k7 LTCC system, and occupies a substrate area of 5.6 × 2.1 × 0.42 mm3 including transitions and a shielding via fence. The filter, including the two grounded coplanar waveguide transmission line (CPWg) to stripline transitions, has a measured insertion loss of 1.5 dB at the center frequency 58 GHz, and a return loss of less than −10 dB over the 11 GHz 3 dB passband.

A Low Loss Fully Embedded Stripline Parallel Coupled BPF for Applications using the 60 GHz Band

This paper presents a low loss fully embedded bandpass filter (BPF) using low temperature co-fired ceramic (LTCC) for multilayer System-in-Package (SiP) and Multi-Chip-Module (MCM) applications, e.g. wireless applications for the unlicensed 60 GHz band. The measured insertion loss was 1.5 dB at the center frequency 58 GHz, and a return loss of less than −10 dB was achieved, including two grounded coplanar waveguide transmission line (CPWg) to stripline transitions. The four layers BPF has a 3 dB bandwidth of about 11 GHz which supplies e.g. broadband and high data rate applications. The whole BPF requires a substrate area of 5.6 × 2.1 × 0.42 mm3 with transitions and a shielding via fence. This BPF suits well for V-band applications in a LTCC package because of the compact dimensions and the good performance.

Compact LTCC band pass filter using high‐Q bondwire inductor for RF system‐in‐package applications

AbstractA low‐temperature cofired ceramics(LTCC)‐embedded bandpass filter (BPF) using a high quality (Q) factor (130) bondwire inductor is proposed for radio frequency (RF) system‐in‐package (SiP) applications. The usage of high‐Q bondwire inductors significantly improves the passband insertion loss (1.35 dB) compared with that (2.0 dB) of embedded spiral inductors at 5.25 GHz and also greatly reduces the device size to 1.000 × 1.500 × 0.675 mm3. The insertion loss and the size of the proposed bondwire filter are the best compared with those of open literature filters. Excellent tolerances of 1.9% and 4.4% are, respectively, measured for the cutoff frequency and the insertion loss. We expect the proposed bondwire filter play an important role to improve the performance and to reduce the sizes of RF SiP circuits. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 1424–1428, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24390

LTCC broadband deep embedded interconnects (DEI) with application for embedded bandpass filter

AbstractCareful design of via transitions intended for use in practical microwave applications is needed to realize the advantages of low‐temperature co‐fired ceramic (LTCC), such as highly integrated buried passive circuits. Grounded coplanar waveguide (GCPW) to asymmetrical stripline vertical interconnects is optimized for thick LTCC substrate. The focus is to develop a vertical transition through thick substrate supporting deep embedded interconnects (DEI). The measured results demonstrate vertical transitions with good performance up to 20 GHz. Embedded LTCC bandpass filter with such vertical transition has been demonstrated with an insertion loss of 2.2 dB and return loss better than −20 dB at 16.2 GHz. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 38: 179–181, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11007

A compact LTCC-based Ku-band transmitter module

Presents design, implementation, and measurement of a three-dimensional (3-D)-deployed RF front-end system-on-package (SOP) in a standard multi-layer low temperature co-fired ceramic (LTCC) technology. A compact 14 GHz GaAs MESFET-based transmitter module integrated with an embedded bandpass filter was built on LTCC 951AT tapes. The up-converter MMIC integrated with a voltage controlled oscillator (VCO) exhibits a measured up-conversion gain of 15 dB and an IIP3 of 15 dBm, while the power amplifier (PA) MMIC shows a measured gain of 31 dB and a 1-dB compression output power of 26 dBm at 14 GHz. Both MMICs were integrated on a compact LTCC module where an embedded front-end band pass filter (BPF) with a measured insertion loss of 3 dB at 14.25 GHz was integrated. The transmitter module is compact in size (400 /spl times/ 310 /spl times/ 35.2 mil/sup 3/), however it demonstrated an overall up-conversion gain of 41 dB, and available data rate of 32 Mbps with adjacent channel power ratio (ACPR) of 42 dB. These results suggest the feasibility of building highly SOP integrated RF front ends for microwave and millimeter wave applications.