A COMPACT MICROSTRIP RAT-RACE COUPLER WITH MODIFIED LANGE AND T-SHAPED ARMS

A compact microstrip rat-race coupler is proposed with a new phase inverter which is realized by a modifled Lange coupling structure with a slotted ground plane and a ∞oating-potential conductor. Based on the even- and odd-mode theory, its parameters are generally synthesized. In order to further miniaturize the rat-race coupler, a T-shaped line is utilized. A prototype operating at 2.0GHz is designed and fabricated for veriflcation. The circumference of our proposed rat-race coupler is only 0.52‚. Its in-phase and out-of-phase bandwidths are also enhanced, with reasonable agreement obtained between its simulated and measured S-parameters.

[1]  Ke Wu,et al.  Accurate Synthesis of Four-Line Interdigitated Coupler , 2009, IEEE Transactions on Microwave Theory and Techniques.

[2]  S.-X. Gong,et al.  A Novel Wilkinson Power Divider for Dual-Band Operation , 2009 .

[3]  A. Moscoso-Mártir,et al.  High Performance 1.8-18ghz 10-dB Low Temperature Co-Fired Ceramic Directional Coupler , 2010 .

[4]  Yi-Chyun Chiou,et al.  Miniaturized Rat Race Coupler With Suppression of Spurious Passband , 2007, IEEE Microwave and Wireless Components Letters.

[5]  Jen-Tsai Kuo,et al.  Miniaturized Rat Race Coupler with Microstrip-to-CPW Broadside-Coupled Structure and Stepped-Impedance Sections , 2007, 2007 IEEE/MTT-S International Microwave Symposium.

[6]  Boon-Kuan Chung,et al.  ULTRA WIDEBAND POWER DIVIDER USING TAPERED LINE , 2010 .

[7]  Bo Li,et al.  A MINIATURIZED BRANCH-LINE COUPLER WITH WIDEBAND HARMONICS SUPPRESSION , 2010 .

[8]  Kimberley W. Eccleston,et al.  Compact planar microstripline branch-line and rat-race couplers , 2003 .

[9]  S. March A Wideband Stripline Hybrid Ring (Correspondence) , 1968 .

[10]  J. Kuo,et al.  GENERALIZED SYNTHESIS OF RAT RACE RING COUPLER AND ITS APPLICATION TO CIRCUIT MINIATURIZATION , 2010 .

[11]  Kuo-Sheng Chin,et al.  Compact Dual-Band Branch-Line and Rat-Race Couplers With Stepped-Impedance-Stub Lines , 2010, IEEE Transactions on Microwave Theory and Techniques.

[12]  V.K. Tripathi,et al.  Compact folded line rat-race hybrid couplers , 2000, IEEE Microwave and Guided Wave Letters.

[13]  Bumman Kim,et al.  Small Wideband Coupled-Line Ring Hybrids With No Restriction on Coupling Power , 2009, IEEE Transactions on Microwave Theory and Techniques.

[14]  A. Abdelaziz,et al.  REALIZATION OF COMPOSITE RIGHT/LEFT-HANDED TRANSMISSION LINE USING COUPLED LINES , 2009 .

[15]  Majeed A. S. Alkanhal COMPOSITE COMPACT TRIPLE-BAND MICROSTRIP ANTENNAS , 2009 .

[16]  Md.C. Velazquez-Ahumada,et al.  Parallel coupled microstrip filters with floating ground-plane conductor for spurious-band suppression , 2005, IEEE Transactions on Microwave Theory and Techniques.

[17]  Quan Xue,et al.  A novel microstrip ring hybrid incorporating a PBG cell , 2001 .

[18]  Jen-Tsai Kuo,et al.  TRANSMISSION ZERO DESIGN GRAPH FOR DUAL-MODE DUAL-BAND FILTER WITH PERIODIC STEPPED-IMPEDANCE RING RESONATOR , 2010 .

[19]  Min-Hang Weng,et al.  DESIGN OF THE COMPACT PARALLEL-COUPLED LINES WIDEBAND BANDPASS FILTERS USING IMAGE PARAMETER METHOD , 2010 .

[20]  Masahiro Muraguchi,et al.  Reduced-size branch-line and rat-race hybrids for uniplanar MMIC's , 1990 .

[21]  Ke Wu,et al.  Size-reduction and band-broadening design technique of uniplanar hybrid ring coupler using phase inverter for M(H)MIC's , 1999 .

[22]  Quan Xue,et al.  Performance enhancement of microwave circuits using parallel-strip line , 2010, IEEE Potentials.

[23]  S. Sanyal,et al.  Reduced-Length Rat-Race Couplers , 2007, IEEE Transactions on Microwave Theory and Techniques.

[24]  Quan Xue,et al.  A Broadband Compact Microstrip Rat-Race Hybrid Using a Novel CPW Inverter , 2007, IEEE Transactions on Microwave Theory and Techniques.

[25]  Chao-Hsiung Tseng,et al.  Compact Rat-Race Coupler Using Shunt-Stub-Based Artificial Transmission Lines , 2008, IEEE Microwave and Wireless Components Letters.

[26]  Z. Lin,et al.  A NOVEL APPROACH TO THE DESIGN OF DUAL- BAND POWER DIVIDER WITH VARIABLE POWER DIVIDING RATIO BASED ON COUPLED-LINES , 2010 .

[27]  T. Itoh,et al.  A compact enhanced-bandwidth hybrid ring using an artificial lumped-element left-handed transmission-line section , 2004, IEEE Transactions on Microwave Theory and Techniques.