The Experts below are selected from a list of 85359 Experts worldwide ranked by ideXlab platform
M Mrozowski - One of the best experts on this subject based on the ideXlab platform.
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a novel Coupling Matrix synthesis technique for generalized chebyshev filters with resonant source load connection
IEEE Transactions on Microwave Theory and Techniques, 2013Co-Authors: Lukasz Szydlowski, Adam Lamecki, M MrozowskiAbstract:This paper reports a novel synthesis method for microwave bandpass filters with resonant source-load connection. In effect, a network realizing N+1 transmission zeros (where N is the number of reflection zeros) is obtained. The method is based on a prototype transversal Coupling Matrix (N+2, N+2) with source and load connected by a resonant circuit formed by a capacitor in parallel with a frequency-invariant susceptance. To complement the proposed synthesis technique, a method of reconfiguring the transversal Coupling Matrix as a more practical cross-coupled circuit is outlined. The technique is based on quickly converging gradient optimization with a cost function involving generalized eigenvalues of the transversal Coupling Matrix and its principal upper and lower submatrices. To illustrate and validate the proposed synthesis procedure, numerical tests have been carried out. Moreover, some aspects of implementation of the resonant connection between source and load were investigated, and experimental verification was performed. A third-order generalized Chebyshev filter with four transmission zeros was designed, fabricated, and tested. The measured results validate the proposed synthesis method.
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A Novel Coupling Matrix Synthesis Technique for Generalized Chebyshev Filters With Resonant Source–Load Connection
IEEE Transactions on Microwave Theory and Techniques, 2013Co-Authors: Lukasz Szydlowski, Adam Lamecki, M MrozowskiAbstract:This paper reports a novel synthesis method for microwave bandpass filters with resonant source-load connection. In effect, a network realizing N+1 transmission zeros (where N is the number of reflection zeros) is obtained. The method is based on a prototype transversal Coupling Matrix (N+2, N+2) with source and load connected by a resonant circuit formed by a capacitor in parallel with a frequency-invariant susceptance. To complement the proposed synthesis technique, a method of reconfiguring the transversal Coupling Matrix as a more practical cross-coupled circuit is outlined. The technique is based on quickly converging gradient optimization with a cost function involving generalized eigenvalues of the transversal Coupling Matrix and its principal upper and lower submatrices. To illustrate and validate the proposed synthesis procedure, numerical tests have been carried out. Moreover, some aspects of implementation of the resonant connection between source and load were investigated, and experimental verification was performed. A third-order generalized Chebyshev filter with four transmission zeros was designed, fabricated, and tested. The measured results validate the proposed synthesis method.
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coupled resonator filters with frequency dependent Couplings Coupling Matrix synthesis
IEEE Microwave and Wireless Components Letters, 2012Co-Authors: Lukasz Szydlowski, Adam Lamecki, M MrozowskiAbstract:This letter presents a novel technique for synthesis of coupled-resonator filters with inter-resonator Couplings varying linearly with frequency. The values of non-zero elements of the Coupling Matrix are found by solving a nonlinear least squares problem involving eigenvalues of Matrix pencils derived from the Coupling Matrix and reference zeros and poles of scattering parameters. The proposed method was verified by numerical tests carried out for various Coupling schemes including triplets and quadruplets for which the frequency-dependent Coupling was found to produce an extra zero.
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bandpass bandstop Coupling Matrix synthesis based on rational representation of scattering parameters
Asia-Pacific Microwave Conference, 2010Co-Authors: Adam Lamecki, M MrozowskiAbstract:A novel formulation of Coupling Matrix synthesis is presented in this paper. The proposed approach uses rational functions of scattering parameters instead of admittance parameters, which allows one to synthesize the the Matrix without necessity of construction of transversal Matrix.
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Bandpass/bandstop Coupling Matrix synthesis based on rational representation of scattering parameters
2010Co-Authors: Adam Lamecki, M MrozowskiAbstract:A novel formulation of Coupling Matrix synthesis is presented in this paper. The proposed approach uses rational functions of scattering parameters instead of admittance parameters, which allows one to synthesize the the Matrix without necessity of construction of transversal Matrix.
Michael J. Lancaster - One of the best experts on this subject based on the ideXlab platform.
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Substrate Integrated Waveguide Filter–Amplifier Design Using Active Coupling Matrix Technique
IEEE Transactions on Microwave Theory and Techniques, 2020Co-Authors: Yang Gao, Xiaobang Shang, Yi Wang, Fan Zhang, Cheng Guo, Yuhuai Liu, Jiashan Liu, Michael J. LancasterAbstract:This article presents a comprehensive active ${N}\,\,+ 4$ Coupling Matrix approach for the design of integrated filter–amplifier. The feedback between gate and drain, which is neglected in a previous work, is considered, which improves the accuracy of the Coupling Matrix model for transistors. More importantly, the relationship between the Coupling Matrix and the noise figure is also established, which extends the Coupling Matrix method to tackle noise-related circuit functions. Substrate integrated waveguide (SIW) filters are used to implement an integrated $X$ -band filter–amplifier design and to validate the design approach in terms of return loss, gain, and noise. Compared with rectangular waveguide, SIW is utilized for its appealing advantages, such as lower production cost, easier fabrication, and most importantly easier integration with active components. A second-order filtering circuit is applied to simultaneously match the input and output of the transistor. The integration reduces the losses from the intermediate networks in conventional designs, which is particularly important when the frequencies go higher. The measurements agree very well with the simulations in terms of S-parameters, gains, and noise figures.
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Coupling Matrix-Based Design of Waveguide Filter Amplifiers
IEEE Transactions on Microwave Theory and Techniques, 2018Co-Authors: Yang Gao, Xiaobang Shang, Jeff Powell, Michael J. LancasterAbstract:This paper extends the conventional Coupling Matrix theory for passive filters to the design of “filter-amplifiers,” which have both filtering and amplification functionality. For this approach, extra elements are added to the standard Coupling Matrix to represent the transistor. Based on the specification of the filter and small-signal parameters of the transistor, the active $N + 3$ Coupling Matrix for the “filter-amplifier” can be synthesized. Adopting the active Coupling Matrix, the last resonator of the filter (adjacent to the transistor) and the Coupling between them are modified mathematically to provide a Chebyshev response with amplification. Although the transistor has a complex impedance, it can be matched to the filter input by the choice of the Coupling structure and the resonator frequency. This is particularly useful as the filter resonators can be of a different construction (e.g., waveguide) to the amplifier (e.g., microstrip). Here, an X-band filter-amplifier is implemented as an example, but the technique is general.
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design of multiple passband filters using Coupling Matrix optimisation
Iet Microwaves Antennas & Propagation, 2012Co-Authors: Xiaobang Shang, Yi Wang, Gemma Nicholson, Michael J. LancasterAbstract:This study presents the design of microwave filters based on the Coupling Matrix approach; determination of the Matrix is based on a hybrid optimisation algorithm which may be applied to cross-coupled filters having diverse topologies. Various filter responses from dual-band to quad-band are given as examples of the approach. The optimisation is performed on the Coupling Matrix and a genetic algorithm (GA) is employed to generate initial values for the control variables for a subsequent local optimisation (sequential quadratic programming search). The novel cost function in this study measures the difference of the frequency locations of reflection and transmission zeros between the response produced by the Coupling Matrix and the ideal response. The ideal response in the form of characteristic polynomials is determined from the filter specifications and generated by a recently developed iterative technique which is capable of realising multi-band filters with different return loss levels. Convergence of the Coupling Matrix optimisation is fast, and no initial values for the control parameters are required by the GA. An eighth-order X-band dual-band waveguide filter with all-capacitive-Coupling irises has been fabricated and measured to verify the design technique. Excellent agreement between simulation and experimental result has been achieved.
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Coupling Matrix synthesis of triple-passband filters using optimisation
2nd Annual Passive RF and Microwave Components Seminar, 2011Co-Authors: Xiaobang Shang, Yi Wang, Michael J. LancasterAbstract:In this paper a Coupling Matrix synthesis procedure based on a combination of global and local optimisations has been presented. The Coupling matrices of two high-order triple-band filters have been synthesized to demonstrate its applicability for cross-coupled filters with complex topologies and frequency responses. Convergence of the optimisation is fast and no initial values for control parameters are required. This technique can be used to synthesize many other multiple-passband filters. These Coupling matrices can be used to produce practical filters with any resonator.
Adam Lamecki - One of the best experts on this subject based on the ideXlab platform.
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a novel Coupling Matrix synthesis technique for generalized chebyshev filters with resonant source load connection
IEEE Transactions on Microwave Theory and Techniques, 2013Co-Authors: Lukasz Szydlowski, Adam Lamecki, M MrozowskiAbstract:This paper reports a novel synthesis method for microwave bandpass filters with resonant source-load connection. In effect, a network realizing N+1 transmission zeros (where N is the number of reflection zeros) is obtained. The method is based on a prototype transversal Coupling Matrix (N+2, N+2) with source and load connected by a resonant circuit formed by a capacitor in parallel with a frequency-invariant susceptance. To complement the proposed synthesis technique, a method of reconfiguring the transversal Coupling Matrix as a more practical cross-coupled circuit is outlined. The technique is based on quickly converging gradient optimization with a cost function involving generalized eigenvalues of the transversal Coupling Matrix and its principal upper and lower submatrices. To illustrate and validate the proposed synthesis procedure, numerical tests have been carried out. Moreover, some aspects of implementation of the resonant connection between source and load were investigated, and experimental verification was performed. A third-order generalized Chebyshev filter with four transmission zeros was designed, fabricated, and tested. The measured results validate the proposed synthesis method.
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A Novel Coupling Matrix Synthesis Technique for Generalized Chebyshev Filters With Resonant Source–Load Connection
IEEE Transactions on Microwave Theory and Techniques, 2013Co-Authors: Lukasz Szydlowski, Adam Lamecki, M MrozowskiAbstract:This paper reports a novel synthesis method for microwave bandpass filters with resonant source-load connection. In effect, a network realizing N+1 transmission zeros (where N is the number of reflection zeros) is obtained. The method is based on a prototype transversal Coupling Matrix (N+2, N+2) with source and load connected by a resonant circuit formed by a capacitor in parallel with a frequency-invariant susceptance. To complement the proposed synthesis technique, a method of reconfiguring the transversal Coupling Matrix as a more practical cross-coupled circuit is outlined. The technique is based on quickly converging gradient optimization with a cost function involving generalized eigenvalues of the transversal Coupling Matrix and its principal upper and lower submatrices. To illustrate and validate the proposed synthesis procedure, numerical tests have been carried out. Moreover, some aspects of implementation of the resonant connection between source and load were investigated, and experimental verification was performed. A third-order generalized Chebyshev filter with four transmission zeros was designed, fabricated, and tested. The measured results validate the proposed synthesis method.
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coupled resonator filters with frequency dependent Couplings Coupling Matrix synthesis
IEEE Microwave and Wireless Components Letters, 2012Co-Authors: Lukasz Szydlowski, Adam Lamecki, M MrozowskiAbstract:This letter presents a novel technique for synthesis of coupled-resonator filters with inter-resonator Couplings varying linearly with frequency. The values of non-zero elements of the Coupling Matrix are found by solving a nonlinear least squares problem involving eigenvalues of Matrix pencils derived from the Coupling Matrix and reference zeros and poles of scattering parameters. The proposed method was verified by numerical tests carried out for various Coupling schemes including triplets and quadruplets for which the frequency-dependent Coupling was found to produce an extra zero.
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Comparison of optimization techniques for Coupling Matrix synthesis using eigenvalue based approach
2012 19th International Conference on Microwaves Radar & Wireless Communications, 2012Co-Authors: Andrzej Jedrzejewski, Lukasz Szydlowski, Adam LameckiAbstract:This paper presents a comparison of the optimization techniques used for Coupling Matrix synthesis problem involving cost function constructed from eigenvalues of Coupling Matrix as well as eigenvalues of principal sub-matrices. Minimization of cost function is performed via three different optimization techniques: linear least-square problem (LL-S), Nelder — Mead (N-M) and quasi — Newton (q-N). The efficiency of linear least-squares method for various starting points is tested. Convergence of the optimization routines are improved through analytically obtained derivatives and trust region (TR) which limits the search area at each iteration step. Examples of the synthesis of cross-coupled filters with symmetric and asymmetric responses are presented.
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bandpass bandstop Coupling Matrix synthesis based on rational representation of scattering parameters
Asia-Pacific Microwave Conference, 2010Co-Authors: Adam Lamecki, M MrozowskiAbstract:A novel formulation of Coupling Matrix synthesis is presented in this paper. The proposed approach uses rational functions of scattering parameters instead of admittance parameters, which allows one to synthesize the the Matrix without necessity of construction of transversal Matrix.
Lukasz Szydlowski - One of the best experts on this subject based on the ideXlab platform.
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a novel Coupling Matrix synthesis technique for generalized chebyshev filters with resonant source load connection
IEEE Transactions on Microwave Theory and Techniques, 2013Co-Authors: Lukasz Szydlowski, Adam Lamecki, M MrozowskiAbstract:This paper reports a novel synthesis method for microwave bandpass filters with resonant source-load connection. In effect, a network realizing N+1 transmission zeros (where N is the number of reflection zeros) is obtained. The method is based on a prototype transversal Coupling Matrix (N+2, N+2) with source and load connected by a resonant circuit formed by a capacitor in parallel with a frequency-invariant susceptance. To complement the proposed synthesis technique, a method of reconfiguring the transversal Coupling Matrix as a more practical cross-coupled circuit is outlined. The technique is based on quickly converging gradient optimization with a cost function involving generalized eigenvalues of the transversal Coupling Matrix and its principal upper and lower submatrices. To illustrate and validate the proposed synthesis procedure, numerical tests have been carried out. Moreover, some aspects of implementation of the resonant connection between source and load were investigated, and experimental verification was performed. A third-order generalized Chebyshev filter with four transmission zeros was designed, fabricated, and tested. The measured results validate the proposed synthesis method.
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A Novel Coupling Matrix Synthesis Technique for Generalized Chebyshev Filters With Resonant Source–Load Connection
IEEE Transactions on Microwave Theory and Techniques, 2013Co-Authors: Lukasz Szydlowski, Adam Lamecki, M MrozowskiAbstract:This paper reports a novel synthesis method for microwave bandpass filters with resonant source-load connection. In effect, a network realizing N+1 transmission zeros (where N is the number of reflection zeros) is obtained. The method is based on a prototype transversal Coupling Matrix (N+2, N+2) with source and load connected by a resonant circuit formed by a capacitor in parallel with a frequency-invariant susceptance. To complement the proposed synthesis technique, a method of reconfiguring the transversal Coupling Matrix as a more practical cross-coupled circuit is outlined. The technique is based on quickly converging gradient optimization with a cost function involving generalized eigenvalues of the transversal Coupling Matrix and its principal upper and lower submatrices. To illustrate and validate the proposed synthesis procedure, numerical tests have been carried out. Moreover, some aspects of implementation of the resonant connection between source and load were investigated, and experimental verification was performed. A third-order generalized Chebyshev filter with four transmission zeros was designed, fabricated, and tested. The measured results validate the proposed synthesis method.
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coupled resonator filters with frequency dependent Couplings Coupling Matrix synthesis
IEEE Microwave and Wireless Components Letters, 2012Co-Authors: Lukasz Szydlowski, Adam Lamecki, M MrozowskiAbstract:This letter presents a novel technique for synthesis of coupled-resonator filters with inter-resonator Couplings varying linearly with frequency. The values of non-zero elements of the Coupling Matrix are found by solving a nonlinear least squares problem involving eigenvalues of Matrix pencils derived from the Coupling Matrix and reference zeros and poles of scattering parameters. The proposed method was verified by numerical tests carried out for various Coupling schemes including triplets and quadruplets for which the frequency-dependent Coupling was found to produce an extra zero.
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Comparison of optimization techniques for Coupling Matrix synthesis using eigenvalue based approach
2012 19th International Conference on Microwaves Radar & Wireless Communications, 2012Co-Authors: Andrzej Jedrzejewski, Lukasz Szydlowski, Adam LameckiAbstract:This paper presents a comparison of the optimization techniques used for Coupling Matrix synthesis problem involving cost function constructed from eigenvalues of Coupling Matrix as well as eigenvalues of principal sub-matrices. Minimization of cost function is performed via three different optimization techniques: linear least-square problem (LL-S), Nelder — Mead (N-M) and quasi — Newton (q-N). The efficiency of linear least-squares method for various starting points is tested. Convergence of the optimization routines are improved through analytically obtained derivatives and trust region (TR) which limits the search area at each iteration step. Examples of the synthesis of cross-coupled filters with symmetric and asymmetric responses are presented.
Yang Gao - One of the best experts on this subject based on the ideXlab platform.
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A Transformation Method of Coupling Matrix Reduction with Hybrid Optimization Algorithm
2020 21st International Conference on Electronic Packaging Technology (ICEPT), 2020Co-Authors: Yanming Zhang, Yang Gao, Ao LiaoAbstract:Coupling Matrix synthesis has been recognized as a widely employed and powerful tool for microwave filter modeling and design. Generally, to obtain a Coupling Matrix whose topology maps to the actual physical structure, the rotation Matrix is used for the Matrix reduction and elimination. However, it is difficult to obtain a precise simplified Matrix through the rotation Matrix method for the corresponding planar resonant circuit filter structure. To overcome the shortcomings of conventional rotation matrices and similar equivalent simplification methods, based on the idea of optimization, we propose a simplification of the Coupling Matrix using a hybrid optimization algorithm. By the proposed algorithm, a simplified Matrix that accurately consistent with the physical structure can be obtained. Firstly, we use the Matrix M R that after the conventional equivalent transformation of the Coupling Matrix as the initial value of the hybrid optimization. Secondly, in order to further obtain the mapped Coupling Matrix, the scattering parameters corresponding to the Coupling Matrix is used to calculate the optimization fitness index, and the filter topology is used as the optimization constraint. Then, a global optimization algorithm is used to obtain a Matrix M G which is similar to the initial Coupling Matrix engineering and the Matrix structure is similar to the topology of the microwave filter. Finally, use a local optimization algorithm to further iteratively optimize the M G until it converges to meet the engineering accuracy requirements. Then, the simplified Matrix M D that is approximately equivalent to the initial Coupling Matrix and corresponds to the filter topology can be obtained.
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Substrate Integrated Waveguide Filter–Amplifier Design Using Active Coupling Matrix Technique
IEEE Transactions on Microwave Theory and Techniques, 2020Co-Authors: Yang Gao, Xiaobang Shang, Yi Wang, Fan Zhang, Cheng Guo, Yuhuai Liu, Jiashan Liu, Michael J. LancasterAbstract:This article presents a comprehensive active ${N}\,\,+ 4$ Coupling Matrix approach for the design of integrated filter–amplifier. The feedback between gate and drain, which is neglected in a previous work, is considered, which improves the accuracy of the Coupling Matrix model for transistors. More importantly, the relationship between the Coupling Matrix and the noise figure is also established, which extends the Coupling Matrix method to tackle noise-related circuit functions. Substrate integrated waveguide (SIW) filters are used to implement an integrated $X$ -band filter–amplifier design and to validate the design approach in terms of return loss, gain, and noise. Compared with rectangular waveguide, SIW is utilized for its appealing advantages, such as lower production cost, easier fabrication, and most importantly easier integration with active components. A second-order filtering circuit is applied to simultaneously match the input and output of the transistor. The integration reduces the losses from the intermediate networks in conventional designs, which is particularly important when the frequencies go higher. The measurements agree very well with the simulations in terms of S-parameters, gains, and noise figures.
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Coupling Matrix Synthesis for the Cascaded Filters
2019 IEEE International Conference on Electron Devices and Solid-State Circuits (EDSSC), 2019Co-Authors: Yang Gao, Fan Zhang, Cheng Guo, Junchao Wang, Yuhuai Liu, Juin J. LiouAbstract:This paper presents a method using $N+4$ Coupling Matrix to represent cascaded filters. With additional columns and rows (corresponding to the transmission line) added to the conventional $N+2$ Coupling Matrix, the $N+4$ Coupling Matrix can be developed. It can also be used to calculate the S-parameter responses of filters cascaded through transmission lines. A cascaded bandpass filter is demonstrated using lumped LC components, and the synthesized Coupling Matrix is verified by the excellent agreement between simulated and calculated results.
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Coupling Matrix-Based Design of Waveguide Filter Amplifiers
IEEE Transactions on Microwave Theory and Techniques, 2018Co-Authors: Yang Gao, Xiaobang Shang, Jeff Powell, Michael J. LancasterAbstract:This paper extends the conventional Coupling Matrix theory for passive filters to the design of “filter-amplifiers,” which have both filtering and amplification functionality. For this approach, extra elements are added to the standard Coupling Matrix to represent the transistor. Based on the specification of the filter and small-signal parameters of the transistor, the active $N + 3$ Coupling Matrix for the “filter-amplifier” can be synthesized. Adopting the active Coupling Matrix, the last resonator of the filter (adjacent to the transistor) and the Coupling between them are modified mathematically to provide a Chebyshev response with amplification. Although the transistor has a complex impedance, it can be matched to the filter input by the choice of the Coupling structure and the resonator frequency. This is particularly useful as the filter resonators can be of a different construction (e.g., waveguide) to the amplifier (e.g., microstrip). Here, an X-band filter-amplifier is implemented as an example, but the technique is general.
