The Influence of a Band-Stop Filter on the Effectiveness of Linearizing the Analog Band-Pass Filter Phase Frequency Response

Introduction. Band-pass filters circuit elements can be calculated by converting low-pass filter (LPF) parameters, which is the prototype of the designed band-pass filter. The conversion causes problems in case calculated values of circuit elements (resistors and capacitors) are out of standard values determined by the GOST standard. Obviously, frequency characteristics of band-pass filters are distorted when replacing the calculated values of circuit elements by the standard ones. The number of circuit elements with values different from standard can be reduced to zero by solving an additional system of equations that connects parameters of designed and reintroduced non-equiripple frequency responses. Objective. The objective of this work is to develop a calculation method of band-pass ladder filters with values of circuit elements corresponding to standard ones. Materials and methods. The filter design process includes two stages. The first stage is a parameters calculation of a polynomial LPF prototype. The calculated parameters are determined as a system of equations solution set. The equations are formed by equating coefficients of variables raised to the same powers in transfer function (TF) expressions of designed and realized filters. Initial characteristics are the filter order and frequency response unevenness. The transition to the standard values of circuit elements can be done when solving another system of equations that connects LPF converted parameters with unknown parameters of reintroduced non-equiripple frequency response. Results. TF of LPF prototypes up to the fifth order and frequency responses of band-pass filters (BPF) and bandrejection filters up to the tenth order are presented. Analytical expressions of non-equiripple and equiripple frequency responses are used to estimate distortions of the latter when a band-pass filter center frequency is tuned by using variable inductors or capacitors. The integral quadratic function of a variable is taken as a measure of real frequency response distortions. The tenth order BPF calculation example is given. Conclusion. The presented calculation methods of band-pass filters and given example demonstrate possibilities of the filter design method based on the systems of non-linear equations solution. In contrast to approximation methods of ideal filter frequency response by using special functions and tabular filters design, the presented method allows high-order filter calculation for any initial requirements without using reference data.

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Design of a Broadband Band-Pass Filter with Notch-Band Using New Models of Coupled Transmission Lines

The Scientific World JOURNAL ◽

10.1155/2014/238717 ◽

2014 ◽

Vol 2014 ◽

pp. 1-12 ◽

Cited By ~ 1

Author(s):

Navid Daryasafar ◽

Somaye Baghbani ◽

Mohammad Naser Moghaddasi ◽

Ramezanali Sadeghzade

Keyword(s):

Frequency Response ◽

Transmission Lines ◽

Band Pass Filter ◽

Pass Filter ◽

New Model ◽

Notch Band ◽

New Models ◽

Basic Parameters ◽

Band Pass ◽

Coupled Transmission Lines

We intend to design a broadband band-pass filter with notch-band, which uses coupled transmission lines in the structure, using new models of coupled transmission lines. In order to realize and present the new model, first, previous models will be simulated in the ADS program. Then, according to the change of their equations and consequently change of basic parameters of these models, optimization and dependency among these parameters and also their frequency response are attended and results of these changes in order to design a new filter are converged.

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A Novel Three-Port Combiner Based on Coaxial Cavity

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.605-607.1924 ◽

2012 ◽

Vol 605-607 ◽

pp. 1924-1928

Author(s):

Su Nan Zhang ◽

Qiang Ye ◽

Chang Wei Luo

Keyword(s):

Return Loss ◽

Ultra Wideband ◽

Band Pass Filter ◽

The Novel ◽

Pass Filter ◽

Coaxial Cavity ◽

Transmission Zero ◽

Band Stop Filter ◽

Band Pass ◽

Good Agreement

In this paper, a novel three-port combiner based on coaxial cavity is presented, which consists of a band-pass filter with a transmission zero and a ultra-wideband band-stop filter, and the combiner is different to the conventional combiner based on microstrip or stripline. The design and simulated results show that the novel combiner has a good performance, which are insert loss more than -0.5dB and return loss less than -20dB between the GSM/DCS/TD band (800-2170MHz) and WLAN band (2400-2500MHz), the isolation in both bands less than -85dB, respectively. In addition, the performances of the novel combiner are demonstrated experimentally, the measured results have good agreement with simulated results.

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Improved RF Metamaterial Band-Pass Filter Design Using CSRR Structures on LCP Substrate

Additional Conferences (Device Packaging HiTEC HiTEN & CICMT) ◽

10.4071/2015dpc-tp61 ◽

2015 ◽

Vol 2015 (DPC) ◽

pp. 001016-001047

Author(s):

Christopher James ◽

Robert N. Dean

Keyword(s):

Frequency Response ◽

Filter Design ◽

Ring Resonators ◽

Band Pass Filter ◽

Split Ring ◽

Pass Filter ◽

Signal Line ◽

Low Pass ◽

Band Pass ◽

High Pass

In the past decade, the emergence of man-made structures with unusual electromagnetic properties not seen in nature—commonly known as “metamaterials”—has generated much interest in designing filters, antennas, lenses, and other devices based on negative values of permittivity (ε) and permeability (μ). Manipulating negative values of these electromagnetic parameters has found applications in communication technology and cloaking research by taking advantage of interesting phenomena such as a negative index of refraction and the reverse Doppler Effect. RF and microwave filters with different frequency responses (low-pass, high-pass, band-pass, and band-stop) can be realized by varying microstrip signal line shapes at a frequency of interest due to the fact that the metamaterial frequency response is dependent on the physical dimensions of the structures. For example, the center frequency of a filter can be determined by adjusting the physical dimensions of metamaterial building blocks called split-ring resonators (SRR) or their duals, complementary split-ring resonators (CSRR). To further metamaterial applications, however, non-planar surfaces and effects of curvature on frequency response must also be considered. In this work, an RF metamaterial filter is presented to demonstrate an improvement in the band-pass frequency response from a previous design at Auburn University by enhancing the upper band behavior of the filter. This is achieved by modifying the metamaterial design on the microstrip device to incorporate new additions to the signal line to combine both high-pass and low-pass metamaterial design concepts, resulting in a band-pass response. The filter is designed using a liquid crystal polymer (LCP) slab as a substrate due in part to its dielectric properties, but also to investigate the filter's performance on a flexible structure. An exploration into the roles of different signal line and CSRR dimensions in filter design is given, and a microstrip filter designed using ANSYS HFSS is shown along with simulation results to verify band-pass filter response. LCP was selected due to its excellent RF properties, its resistance to moisture absorption, and its ability to be micromachined.

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Switchable Terahertz Band-Pass/Band-Stop Filter Enabled by Hybrid Vanadium Dioxide Metamaterial

Advances in Condensed Matter Physics ◽

10.1155/2020/3902835 ◽

2020 ◽

Vol 2020 ◽

pp. 1-6

Author(s):

Ying Chen ◽

Jianwei Cheng ◽

Chaowu Liang

Keyword(s):

Vanadium Dioxide ◽

Surface Current ◽

Center Frequency ◽

Pass Band ◽

Metallic State ◽

Band Pass Filter ◽

Pass Filter ◽

Band Stop Filter ◽

Band Pass ◽

Functional Components

To date, little research has been carried out on the integration of switchable and diversified functionalities into a single metamaterial in the terahertz (THz) range. Here, a hybrid vanadium dioxide (VO2) metamaterial was designed with switchable properties of band-pass filter and band-stop filter in the frequency range of 0.3–1.6 THz. Simulations demonstrated that under TE polarization, the proposed system acted as band-stop filter with the center frequency of 0.95 THz when VO2 is in the insulating state. Upon the transformation of VO2 into the metallic state, the proposed system behaved as a band-pass filter with a transmittance of >80%. The physical mechanism of the band-pass/band-stop conversion was examined by analyzing the surface current distribution of the designed device. The switchable characteristics of this structure can enable its wide application in tunable THz functional components such as amplitude modulators, polarization control, and intelligent switches.

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Simulasi Perancangan Filter Analog dengan Respon Chebyshev

ELKOMIKA Jurnal Teknik Energi Elektrik Teknik Telekomunikasi & Teknik Elektronika ◽

10.26760/elkomika.v1i2.106 ◽

2013 ◽

Vol 1 (2) ◽

pp. 106

Author(s):

RUSTAMAJI RUSTAMAJI ◽

ARSYAD RAMADHAN DARLIS ◽

SOLIHIN SUPARMAN

Keyword(s):

User Interface ◽

Graphical User Interface ◽

Band Pass Filter ◽

Pass Filter ◽

Low Pass Filter ◽

Band Stop Filter ◽

Low Pass ◽

Band Pass ◽

High Pass ◽

Filter Response

ABSTRAKDalam suatu sistem komunikasi penggunaan rangkaian filter sangat penting. Salah satu cara untuk memudahkan dalam perancangan sebuah filter dilakukanlah teknik simulasi. Penelitian ini bertujuan untuk merancang simulasi yang menghasilkan respon filter jenis chebyshev serta menghasilkan nilai komponen induktor (L) dan kapasitor (C) yang dibutuhkan untuk merangkai filter. Simulasi yang dirancang pada penelitian ini menggunakan Graphical User Interface (GUI). Dari simulasi yang dilakukan, didapatkan respon Chebyshev pada low pass filter, high pass filter, band pass filter, dan band stop filter sudah sesuai dengan input yang dimasukkan ke dalam parameter program dan sesuai dengan teori respon filter Chebyshev. Hasil Simulasi dari rangkaian band pass filter dan band stop filter dengan menggunakan Electronic Workbench (EWB), menunjukkan respon dengan pergeseran frekuensi sebesar 0,1 kHz lebih tinggi dari frekuensi yang diharapkan.Kata Kunci: filter, Chebyshev, band, respon frekuensi. ABSTRACTOn communication system using filter is very important. One way to simplify the design of filter undertaken a simulation technique. This research aims to design a simulation that generates the filter response of chebyshev and generate the value component of the inductor (L) and capacitor (C) that needed for constructing the filter. This Simulation using Graphical User Interface (GUI). From result simulation, response in low pass filter, high pass filter, band pass filter, band stop filter and is in compliance with the input entered into the program and in accordance with the theory of Chebyshev filter response. The simulation of the band pass filter and bands stop filter by using electronic workbench ( EWB ), show a response with shifts frequency of 0.1 khz higher than frequency expected.Keywords: filter, Chebyshev, band, frequency respons

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Design of Dual Ultra–Wideband Band–Pass Filter Using Stepped Impedance Resonator λg/4 Short Stubs and T–Shaped Band-Stop Filter

Electronics ◽

10.3390/electronics10161951 ◽

2021 ◽

Vol 10 (16) ◽

pp. 1951

Author(s):

Kicheol Yoon ◽

Kwanggi Kim

Keyword(s):

Wireless Communication ◽

Insertion Loss ◽

Communication Systems ◽

Dual Band ◽

Wireless Communication Systems ◽

Band Pass Filter ◽

Pass Filter ◽

Band Stop Filter ◽

Band Pass ◽

Stepped Impedance Resonator

Portable wireless communication systems are increasingly in demand in small sizes for human convenience. In wireless communication systems, the performance, size, and unit cost are very important. A band−pass filter is important to sharp cut–off frequency characteristics, size, and frequency selectivity in wireless communication systems. The band−pass filter has three types of techniques in the transmission−zero method, stub−loaded resonator, and stepped impedance resonator for the sharp cut−off frequency characteristic, adjustable bandwidth, and excellent frequency response characteristics. To obtain these characteristics, the impedance ratio and length of a stub are mainly adjusted. It also utilizes a multi–mode technique to increase bandwidth. However, it is analyzed that the problem of reducing the size of the device still remains. To solve these problems, the paper is applied to a stub−loaded resonator and a stepped impedance resonator to control the impedance ratio and the length of the stub to obtain the results of the transmission−zero method, bandwidth control, and size reduction through the folded structure. Dual−band bandwidth was secured by integrating a T−shaped band−stop filter. The designed band–pass filter has center frequencies of 243 GHz and 7.49 GHz, and the insertion loss of a proposed band−pass filter is 0.102 dB and 0.103 dB. Additionally, the return loss of a proposed band−pass filter is 19.13 dB and 19.96 dB, respectively. The bandwidth of a filter is 120% and 105%, respectively. The size of the filter is 0.0708 λg × 0.0533 λg. The designed filter has a good skirt phenomenon, small size, low insertion loss, and dual−band characteristics.

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Automation of Bandwidth Re-design and its Applications in Amplifier Tuned Oscillators Based on Nullors

Journal of Circuits System and Computers ◽

10.1142/s0218126621500547 ◽

2020 ◽

pp. 2150054

Author(s):

R. Rohith Krishnan ◽

S. Krishnakumar

Keyword(s):

Frequency Response ◽

Narrow Band ◽

Center Frequency ◽

Band Pass Filter ◽

Amplitude Control ◽

Pass Filter ◽

Feedback Network ◽

Reference Circuit ◽

Band Pass ◽

Model Circuit

In this paper, the method for the design automation of a narrow band-pass amplifier, and hence the amplifier tuned oscillator is discussed. A fixator approach is utilized in this method to design the narrow band-pass amplifiers and a reference circuit is required for this process. The fixator–norator pair helps to generate an extra sub-circuit, generally the feedback network; the addition of this sub-circuit in the actual amplifier circuit will modify the frequency response of the amplifier. The amplifier now behaves like an active narrow band-pass filter, which exactly follows the frequency response of the model circuit. This can be turned into an oscillator by providing positive feedback. Such a circuit possesses independent frequency and amplitude control. Hence, the re-designed circuit can be employed as an active filter or an oscillator at the selected center frequency. In addition to the technical merits, the proposed method has pedagogical importance. Few case studies are worked out in this paper to demonstrate the method.

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Development of a Microwave Sensor for Solid and Liquid Substances Based on Closed Loop Resonator

Sensors ◽

10.3390/s21248506 ◽

2021 ◽

Vol 21 (24) ◽

pp. 8506

Author(s):

Aiswarya S ◽

Sreedevi K. Menon ◽

Massimo Donelli ◽

Meenu L

Keyword(s):

Dielectric Property ◽

Experimental Validation ◽

Closed Loop ◽

Food Samples ◽

Band Pass Filter ◽

Pass Filter ◽

Dielectric Sensor ◽

Microwave Sensor ◽

Band Stop Filter ◽

Band Pass

In this work, a compact dielectric sensor for the detection of adulteration in solid and liquid samples using planar resonators is presented. Six types of filter prototypes operating at 2.4 GHz are presented, optimized, numerically assessed, fabricated and experimentally validated. The obtained experimental results provided an error less than 6% with respect to the simulated results. Moreover, a size reduction of about 69% was achieved for the band stop filter and a 75% reduction for band pass filter compared to standard sensors realized using open/short circuited stub microstrip lines. From the designed filters, the miniaturised filter with Q of 95 at 2.4 GHz and size of 35 mm × 35 mm is formulated as a sensor and is validated theoretically and experimentally. The designed sensor shows better sensitivity, and it depends upon the dielectric property of the sample to be tested. Simulation and experimental validation of the designed sensor is carried out by loading different samples onto the sensor. The adulteration detection of various food samples using the designed sensor is experimentally validated and shows excellent sensing on adding adulterants to the original sample. The sensitivity of the sensor is analyzed by studying the variations in resonant frequency, scattering parameters, phase and Q factor with variation in the dielectric property of the sample loaded onto the sensor.

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