Microstrip Hairpin Filter Research Articles

Novel neural network modeling method and applications

Neural networks play an important role for designing the parametric model of electromagnetic structures. The current neural network methods are unfit for a circuit model with many input variables because it is costly to extract a large number of the training data and test data to complete the highly nonlinear mapping approximation. This article proposes a new neural network modeling method-the multidimensional neural network model, which can be used to solve the issue of multivariable radiofrequency and microwave passive device modeling. The entire multidimensional neural network modeling problem is simplified into a set of neural network submodels through decomposition method. Then the submodels are combined into an equivalent model, and the final entire model is produced through the neural-network mapping model developed with the submodels and equivalent model. A microstrip hairpin filter model is developed using the proposed method. The simulation results show the correctness and the effectivity of the proposed method. © 2015 Wiley Periodicals, Inc. Int J RF and Microwave CAE 25:769-779, 2015.

Rapid Yield Estimation and Optimization of Microwave Structures Exploiting Feature-Based Statistical Analysis

In this paper, we propose a simple, yet reliable methodology to expedite yield estimation and optimization of microwave structures. In our approach, the analysis of the entire response of the structure at hand (e.g., $S$ -parameters as a function of frequency) is replaced by response surface modeling of suitably selected feature points. On the one hand, this is sufficient to determine whether a design satisfies given performance specifications. On the other, by exploiting the almost linear dependence of the feature points on the designable parameters of the structure, reliable yield estimates can be realized at low computational cost. Our methodology is verified using two examples of waveguide filters and one microstrip hairpin filter and compared with conventional Monte Carlo analysis based on repetitive electromagnetic simulations, as well as with statistical analysis exploiting linear response expansions around the nominal design. Finally, we perform yield-driven design optimizations on these filters.

Optimum Design of Novel UWB Multilayer Microstrip Hairpin Filters with Harmonic Suppression and Impedance Matching

Optimum design of a novel ultra-wideband multilayer microstrip hairpin filter is presented, providing for harmonic suppression and impedance matching between source and load impedances. The theory of N-coupled transmission lines is employed to obtain an equivalent circuit for development of a design procedure based on the method of least squares. A prototype model of proposed two-layer filter of order 5 is fabricated for 3.1–10.6 GHz. The dimensions of designed filter are 23 mm × 7 mm. The insertion loss in the passband varies from 0.3 dB to 3 dB (in the worst case at the edge of passband) and in the stopband is about 30 dB up to 20 GHz. Its group delay in the UWB region is about 0.5 ns. Close agreement among the filter frequency responses as obtained by the proposed method, full-wave computer simulation softwares, and measurement data verify the effectiveness of the proposed filter structure and design methods.

Reliability of Suspended Bridges on Superconducting Microstrip Filters Using MEMS Switches

This work proposes to use capacitive micro-electro-mechanical systems (MEMS) switches built on a superconducting microstrip hairpin filter to investigate the reliability of MEMS for long term survivability. This device is made of a YBa <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> Cu <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">7</sub> thin film deposited on a 20 mm × 20 mm LaAlO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> substrate by pulsed laser deposition and BaTiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> by RF magnetron sputtering, which is utilized as a dielectric insulation layer at the switching points of contact. The major concern for capacitive MEMS switches is stiction between the gold suspended bridge membrane (top layer) and the dielectric material (bottom layer). The main failure mode results from charge build-up at the bottom layer which in turn depends on the actuation voltage. The actuation voltage measured at room and cryogenic temperature is used to derive and calculate the Young's modulus formula which takes into consideration the device geometry, residual stress and mechanical properties of the device. Modified Young's modulus equation will be validated through reliability data of membrane actuation and failure mode. This equation will in turn be used in modeling other RF MEMS devices operating at cryogenic temperatures.

Design of a Compact Hairpin Filter with Spurious Suppression

In this paper, a new method for suppressing the first spurious passband in microstrip hairpin filter is proposed. For this purpose, meandered shaped coupled lines are used instead of conventional coupled lines. Furthermore, by using this method, a size reduction of 50% is achieved. Simulated and measured results show that the modified bandpass hairpin filter presents a rejection level exceeding 35 dB in the first spurious passband.

Harmonics blocking in hairpin filter using Defected Microstrip Structure

In this paper, it is demonstrated that the first and second spurious passbands suppression in microstrip hairpin filters can be achieved by simply patterning appropriate geometries of several Defected Microstrip Structure (DMS) in parallel coupled sections. By properly tuning DMS resonator dimensions, multiple transmission zeros can be generated in the vicinity of spurious harmonics and a wide stopband can be obtained. Experimental results verify that 25dB and 40dB suppression for the first and the second harmonics, respectively, without affecting the main passband response.

Combining Coarse and Fine Models for Optimal Design

In this article we reviewed the implicit space mapping concept. We illustrated it using a simple tapped-line microstrip filter example. We demonstrated the robustness of our approach by performing an accurate design of a microstrip hairpin filter. A detailed and easy-to-follow design optimization procedure was provided and the Agilent ADS implementation of the algorithm was described. A good electromagnetically validated design in Sonnet em was obtained in a few fine model simulations. Implicit space mapping is a simple approach to combine a circuit-theory based CAD model and an EM simulator model to achieve fast and accurate optimal design and modeling.

Design, simulation, and fabrication of a MEMs switched superconducting microstrip hairpin filter

High performance high T c superconductor based series micro electromechanical system (MEMs) switches have been utilized to switch between a bandpass hairpin filter, center frequency f 0 = 2.5 GHz, and BW of 250 MHz, and a through transmission line. This was accomplished with four switches actuated in pairs, one pair at a time. When the first pair is actuated, the through transmission line is capacitively connected between the input and output ports; accordingly, the system behaves as a throughline. When the second pair of switches is actuated, the bandpass filter is coupled to the input and output ports; thus a corresponding bandpass response is obtained. The design is implemented on a YBa 2Cu 3O 7 thin film deposited on a 15 mm × 15 mm LaAlO 3 substrate by pulsed laser deposition. BaTiO 3 deposited by RF magnetron sputtering is utilized as the insulation layer at the switching points of contact. The advantages and issues of this structure and its fabrication details are discussed along with simulations and experimental data.

Design and Fabrication of Two Switch Superconducting Microstrip Hairpin Filters Using Series MEMS Switches

A superconductor circuit based on series Micro- Electro-Mechanical (MEM) switches is utilized to switch between two bandpass hairpin filters with 200 MHz bandwidth and nominal center frequencies of 2.1 GHz and 2.6 GHz. This is accomplished using 4 switches actuated in pairs, one pair at a time. When one pair is actuated the first bandpass filter is coupled to the input and output ports. When the other pair is actuated the second bandpass filter is coupled to the input and output ports, thus corresponding output responses are obtained. The device is made of YBa2Cu3O7 thin film deposited on a 20 mm times 20 mm LaAlO3 substrate by pulsed laser deposition. BaTiO3 deposited by RF magnetron sputtering is utilized as the insulation layer at the switching points of contact. Fabrication details are discussed along with simulation data and test results.

NOVEL MICROSTRIP BANDPASS FILTERS WITH TRANSMISSION ZEROS

Some design methods for band-pass filters based on half- wavelength resonators have been proposed. The main feature of these methods is that n or n + 1transmission zeros can be generated for a structure composed of n resonators. To demonstrate the usefulness of the proposed filter structures, three kinds of two-pole compact microstrip hairpin filters are designed and fabricated. Good agreement between measured and simulated data has been demonstrated.

High isolation and compact size microstrip hairpin diplexer

Since conventional microstrip hairpin filter and diplexer are inherently formed by coupled-line resonators, spurious response and poor isolation performance are unavoidable. This letter presents a simple technique that is suitable for an inhomogeneous structure such as microstrip to cure such poor performances. The technique is based on the stepped impedance coupled-line resonator and is verified by the experimental results of the designed 0.9GHz/1.8GHz microstrip hairpin diplexer.

Multiple-coupled microstrip hairpin-resonator filter

This letter presents the design of six-resonator multiple-coupled microstrip filter. A low-pass prototype of six-resonator multiple-coupled filter is developed first based on the conventional Chebyshev filter. The characteristics of attenuation poles located on both sides of the frequency response are described. According to the low-pass prototype, the design of a six-resonator multiple-coupled microstrip hairpin filter at 6 GHz is completed with the aid of EM simulation. The experimental results are demonstrated and discussed.

Superconducting microstrip hairpin filter with BaTiO/sub 3/ patches

A high temperature superconducting microstrip line hairpin filter with BaTiO/sub 3/ has been designed and fabricated. The design and the filter simulation were done using Genesys software from Eagleware. In order to maximize the quality factor of the filter, the microstrip lines were made of superconducting YBa/sub 2/Cu/sub 3/O/sub 7/. A YBa/sub 2/Cu/sub 3/O/sub 7/ thin film was deposited on a LaAlO/sub 3/ single crystal substrate using pulsed laser deposition. The microstrip line hairpin filter was then patterned and tested at cryogenic temperatures. A BaTiO/sub 3/ thin film was then deposited and patterned to form patches between the resonators. Microwave tests of the filter with and without the BaTiO/sub 3/ patches were performed at low temperatures. The filter has measured center frequency of 1.65 GHz with a bandwidth of 20 MHz. The results show the effect of using BaTiO/sub 3/ patches on top of YBa/sub 2/Cu/sub 3/O/sub 7/. The most current results on the performance of the filter will be presented.