Design of Wide Passband/Stopband Microstrip Bandpass Filters With the Stepped Coupled Line

Novel wide passband microstrip bandpass filters with broader stopbands are provided in this paper. The proposed bandpass filters are composed of the stepped coupled line and two short-circuited stubs. The electrical length of the stepped coupled line is a quarter of wavelength so that the proposed filter is compact size. Moreover, the stepped coupled line with weak-strong-weak coupling results in a wide stopband. Furthermore, with short-circuited stubs connected at the input/output port, there is a steeper passband skirt and broader passband. In addition, the agreement between theoretical prediction and measurement validates our proposed structure.

[1]  M. Makimoto,et al.  Bandpass Filters Using Parallel Coupled Strip-Line Stepped Impedance Resonators , 1980 .

[2]  Kyung-Whan Yeom,et al.  An EM Tuning Procedure for Planar Filters Based on Individual Resonator Decomposition , 2008, IEEE Microwave and Wireless Components Letters.

[3]  Jae-Bong Lim,et al.  A design of the harmonic rejection low-pass filter using high impedance defected-ground microstrip lines , 2004, 34th European Microwave Conference, 2004..

[4]  Ching-Wen Tang,et al.  Wide Stopband Parallel-Coupled Stacked SIRs Bandpass Filters With Open-Stub Lines , 2006, IEEE Microwave and Wireless Components Letters.

[5]  Ching-Wen Tang,et al.  Design of Planar Complex Impedance Transformers With the Modified Coupled Line , 2012, IEEE Transactions on Components, Packaging and Manufacturing Technology.

[6]  T. Itoh,et al.  Design of an Overlay Directional Coupler by a Full-Wave Analysis , 1983, 1983 IEEE MTT-S International Microwave Symposium Digest.

[7]  Mau-Phon Houng,et al.  A novel cross-shape DGS applied to design ultra-wide stopband low-pass filters , 2006, IEEE Microwave and Wireless Components Letters.

[8]  S.L. March,et al.  Phase Velocity Compensation in Parallel-Coupled Microstrip , 1982, 1982 IEEE MTT-S International Microwave Symposium Digest.

[9]  M. Esa,et al.  Harmonic suppressed single groove PCML bandpass filter , 2009, 2009 European Microwave Conference (EuMC).

[10]  J. Kuo,et al.  Design of microstrip bandpass filters with a dual-passband response , 2005, IEEE Transactions on Microwave Theory and Techniques.

[11]  W. Surakampontorn,et al.  Stepped-Impedance Coupled Resonators for Implementation of Parallel Coupled Microstrip Filters With Spurious Band Suppression , 2012, IEEE Transactions on Microwave Theory and Techniques.

[12]  Chi-Hsueh Wang,et al.  Coplanar-Waveguide-Fed Microstrip Bandpass Filters With Capacitively Broadside-Coupled Structures for Multiple Spurious Suppression , 2007, IEEE Transactions on Microwave Theory and Techniques.

[13]  S. Cohn.  Parallel-Coupled Transmission-Line-Resonator Filters , 1958 .

[14]  E. Pistono,et al.  Compact filters based on stub-loaded parallel-coupled resonators , 2010, The 40th European Microwave Conference.

[15]  C. Quendo,et al.  Synthesis of dual behavior resonator (DBR) filters with integrated low-pass structures for spurious responses suppression , 2006, IEEE Microwave and Wireless Components Letters.

[16]  Lin Li,et al.  A compact wideband microstrip bandpass filter using parallel‐coupled‐lines with periodical grooves , 2009 .

[17]  Amin M. Abbosh,et al.  Design Method for Ultra-Wideband Bandpass Filter With Wide Stopband Using Parallel-Coupled Microstrip Lines , 2012, IEEE Transactions on Microwave Theory and Techniques.

[18]  I. J. Bahl.  Capacitively compensated high performance parallel coupled microstrip filters , 1989, IEEE MTT-S International Microwave Symposium Digest.

[19]  Jen-Tsai Kuo,et al.  Microstrip stepped impedance resonator bandpass filter with an extended optimal rejection bandwidth , 2003 .

[20]  Jin-Koo Rhee,et al.  Microstrip line directional couplers with high directivity , 2004 .

[21]  S. Amari,et al.  A novel lowpass filter with ultra-wide stopband and improved q-factor performance using H-Defected Ground Structure (DGS) , 2007, 2007 IEEE Antennas and Propagation Society International Symposium.

[22]  Leo Young,et al.  The analytical equivalence of TEM-mode directional couplers and transmission-line stepped-impedance filters , 1963 .

[23]  I. Gil,et al.  Spurious passband suppression in microstrip coupled line band pass filters by means of split ring resonators , 2004, IEEE Microwave and Wireless Components Letters.

[24]  Yue Ping Zhang,et al.  Dual-Band Microstrip Bandpass Filter Using Stepped-Impedance Resonators With New Coupling Schemes , 2006, IEEE Transactions on Microwave Theory and Techniques.

[25]  Md.C. Velazquez-Ahumada,et al.  Parallel coupled microstrip filters with ground-plane aperture for spurious band suppression and enhanced coupling , 2004, IEEE Transactions on Microwave Theory and Techniques.

[26]  Txema Lopetegi,et al.  New microstrip "Wiggly-Line" filters with spurious passband suppression , 2001 .

[27]  R. Levy.  Transmission-line directional couplers for very broad-band operation , 1965 .

[28]  I.D. Robertson,et al.  Inductively Compensated Parallel Coupled Microstrip Lines and Their Applications , 2006, IEEE Transactions on Microwave Theory and Techniques.

[29]  M.S. Song,et al.  An implementation of harmonic-suppression microstrip filters with periodic grooves , 2004, IEEE Microwave and Wireless Components Letters.

[30]  Chun-Hsiang Chi,et al.  Miniaturized spurious passband suppression microstrip filter using meandered parallel coupled lines , 2005, IEEE Transactions on Microwave Theory and Techniques.

[31]  Yng-Huey Jeng,et al.  New high-directivity coupler design with coupled spurlines , 2004, IEEE Microwave and Wireless Components Letters.

[32]  Ching-Wen Tang,et al.  A Microstrip Bandpass Filter With Ultra-Wide Stopband , 2008, IEEE Transactions on Microwave Theory and Techniques.

[33]  Wen-Hua Tu,et al.  Compact microstrip bandstop filter using open stub and spurline , 2005, IEEE Microwave and Wireless Components Letters.

[34]  J. Kuo,et al.  Design of parallel-coupled microstrip filters with suppression of spurious resonances using substrate suspension , 2004, IEEE Transactions on Microwave Theory and Techniques.

[35]  Kam-Weng Tam,et al.  Miniaturized parallel coupled-line bandpass filter with spurious-response suppression , 2005 .

[36]  G. I. Zysman,et al.  Coupled Transmission Line Networks in an Inhomoge neous Dielectric Medium , 2017 .

[37]  Ching-Wen Tang,et al.  Miniaturised wide stopband rejected microstrip filter with coupled spur-lines , 2006 .

[38]  M. Dydyk,et al.  Microstrip directional couplers with ideal performance via single-element compensation , 1999 .