Integrated Waveguide Bandpass Filter Research Articles

Ku-Band SIW Filter with High Fractional Bandwidth Optimized Using Feed Forward Back Propagation ANN

An Artificial Neural Network (ANN) based Substrate Integrated Waveguide Band Pass Filter (SIW BPF) is proposed in this paper. A Feed Forward Back Propagation Neural Network (FF-BP NN) is utilized to optimize the filter dimensions. The Gradient Descent with Momentum and Adaptive Learning Rate algorithm is used to train the network at a learning rate of 0.01. The high pass characteristics of the SIW is converted into band pass by incorporating U slots on its top plane. Defected Ground Structure (DGS) is utilized in the bottom plane to improve the impedance matching. To validate, the prototype is fabricated using RT/Duroid 5880 and tested. The proposed filter has a center frequency at 14.68 GHz with a wide pass band from 12.92 to 16.43 GHz with a 3-dB Fractional Bandwidth (FBW) of 24%, return loss more than 20 dB and insertion loss of about 1.9 dB within the pass band. The filter has a small dimension of about 0.63 λ g 2 , where λ g is the guided wavelength at the center frequency. This filter offers wide passband, smaller size, low insertion loss, good return loss and it is useful in Ku-band satellite communication applications.

Design of miniaturized high selectivity folded substrate integrated waveguide band pass filter with Koch fractal

ABSTRACTThis paper proposes the design of a novel double folded substrate integrated waveguide (FSIW) band pass filter (BPF) based on Koch space-filling curve (SFC). The folded SIW filter is incorporated with first and second iteration levels of Koch curve on central conducting layer. A prototype of second iteration Koch fractal FSIW BPF has been fabricated using substrate having dielectric constant 2.55 and thickness 0.508 mm for each layer and then tested. The fabricated second order filter has merits of compact size (0.204 λ02), high roll off rate (82.2 dB/GHz) and low insertion loss (<0.85 dB) in the X band.

Cost-effective and Green Manufacturing Substrate Integrated Waveguide (SIW) BPF for Wireless Sensor Network Applications

This paper presents a comparison between innovative technique for implementation of substrate integrated waveguide band pass filter centered at 4 GHz and conventional PCB results . Two poles filter is designed, simulated and fabricated. The novel fabrication process technique is based on green manufacturing where physical etching of metal layer of aluminum is glued on paper substrate. The pass band filter is composed of two resonant adjacent and symmetric cavities separated by a coupling iris. The same topology is adopted with conventional substrate and PCB technology to validate the new technique results. The bandwidth achieved is almost four times wider than found with PCB technology developed for UWB applications. The proposed technique keeps the advantages of conventional SIW technology including low profile, compact size, complete shielding, easy fabrication, low cost for mass production as well as convenient integration with planar waveguide components including transitions. Moreover, the flexible quality of paper offer the possibility to fabricate conformal shapes of SIW components which is not possible with conventional rigid substrates made with PCB technology . In addition to the advantages of eco friendly, renewable, light weight , and ultra low cost materials

In brief

PAGE 1615 An algorithm using backlog information for slot allocation in satellite-based sensor systems based on Quality of Service (QoS) fairness has been developed by a team from China. The group used delay performance as a measure of QoS, and focussed on long term rather than short term fairness. PAGE 1584 A group based in Germany have used liquid crystal as a tuneable dielectric material to produce a continuously tuneable substrate integrated waveguide band pass filter. The device has a high Q-factor comparable to substrate integrated waveguides with other types of tuneable material, but achieves operating frequencies ten times as high. Simulations show that the system could improve performance by at least 10% PAGE 1587 Authors from the USA present a useful document on achieving and maintaining two decades of bandwidth with monolithic microwave integrated circuit (MMIC) distributed amplifiers. According to the authors, achieving this level of performance can be difficult even when suppliers indicate it can be achieved with their devices. The filter is continuously tuneable within a tuning range of 610 MHz PAGE 1563 Using leather as a substrate, a team from India have designed and fabricated a tri-band substrate integrated waveguide based antenna. The antenna, which uses a combination of conducting and non-conducting leather materials, is compact and flexible, and directs radiation away from the user. The paper also outlines ways to improve devices with lower performance PAGE 1591 The performances and architecture of a multilevel driver for Pulse Amplitude Modulation (PAM) formats is reported on by a team based in France and the USA. The device is designed and fabricated in InP double-heterojunction bipolar transistor technology, and is developed for short reach and long haul networks. The antenna is designed for use in the ISM, WiMAX and Military Applications bands The device can generate PAM-2, PAM-4 and PAM-8 outputs

A Ka-Band Bandpass Filterusing U-Shape Resonators Based on LTCC Technology

This paper demonstrates a new Low Temperature Co-fired Ceramic (LTCC) U-shape resonator. Based on this 3D structure, a Ka-band Substrate Integrated Waveguidebandpass filter isdesigned. Compared with the conventional two dimensional PCB, LTCC technology achieveshigher Qe factor, higher density, smaller size, and lower cost. EM simulator HFSS is employed in determining and optimizingthephysical dimension of the filter.The filter's simulation results showfractional bandwidth (FBW) of3.94% centered at 34.7 GHzwith insertion loss of -1.2 dB and return loss of -20 dB in the passband. The attenuation of -30dB is obtained at 32.8 GHz and 36.8 GHz.

Low-Loss Integrated-Waveguide Passive Circuits Using Liquid-Crystal Polymer System-on-Package (SOP) Technology for Millimeter-Wave Applications

In this paper, we show a low-loss integrated waveguide (IWG), microstrip line-to-IWG transition, IWG bandpass filter (BPF), and system-on-package (SOP) using a liquid-crystal polymer (LCP) substrate, which can be used toward SOP technology for millimeter-wave applications. The proposed IWG can be used as a low-loss millimeter-wave transmission line on this substrate. The measured insertion loss of the IWG is -0.12 dB/mm and the measured insertion loss of two microstrip line-to-IWG transitions is -0.14 dB at 60 GHz. The evaluated IWG filter is demonstrated as the pre-select filter for RF front-end modules at the millimeter-wave band. The fabricated three-pole BPF at a center frequency of 61.1 GHz has specifications: a 3-dB bandwidth of approximately 13.4% (~8.4 GHz), an insertion loss of -1.8 dB at the center frequency of 61.1 GHz, and a rejection of >15 dB over the passband. The proposed IWG can also be used as a low-loss millimeter-wave feed-through transition and interconnection between the monolithic microwave integrated circuit and the module instead of the vertical via structure. In terms of a SOP on LCP for millimeter-wave applications, the top face of the IWG does not have any electromagnetic effects, and a package lid can be attached to provide a hermetic sealing. These low-loss IWG circuits on LCP can easily be used in many millimeter-wave packaging applications