论文信息 - A MINIATURIZED BRANCH-LINE COUPLER WITH WIDEBAND HARMONICS SUPPRESSION

A MINIATURIZED BRANCH-LINE COUPLER WITH WIDEBAND HARMONICS SUPPRESSION

This paper presents a miniaturized branch-line coupler with suppression of wideband harmonics based on a unit of transmission-line section with triple-stub. This fundamental unit produces three transmission zeros and exhibits wide stopband response due to the triple stubs. It is used to replace a quarter-wavelength line in conventional branch-line coupler, leading to size reduction and wideband harmonics suppression. The closed-form equations are given for the coupler design. As an example, a branch-line coupler operating at 1.0GHz is designed, fabricated and measured. Measurements agree well with simulations, and show that the proposed branch-line coupler occupies 56% size of a conventional one and achieves wideband harmonics suppression (better than 17dB) from 1.8GHz to 6.4GHz. The 2nd, 3rd, 4th, 5th, and 6th harmonics are suppressed better than 34dB, 19dB, 30dB, 17dB, and 32dB, respectively. With the theoretical analyses and practical results, it is shown that the proposed one has the advantages of simple structure, convenient analysis and wideband harmonics suppression.

Bo Li | Wen Wu | Xidong Wu

[1] A.B. Guntupalli,et al. Sharp-Rejection Ultra-Wide Bandstop Filters , 2009, IEEE Microwave and Wireless Components Letters.

[2] Ajay Chakrabarty,et al. Design of miniaturised branch-line and rat-race hybrid couplers with harmonics suppression , 2009 .

[3] HARMONIC SUPPRESSION OF BRANCH-LINE AND RAT-RACE COUPLER USING COMPLEMENTARY SPILT RING RESONATORS (CSRR) CELL , 2008 .

[4] Shaoqiu Xiao,et al. A Compact Slow-Wave Microstrip Branch-Line Coupler With High Performance , 2007, IEEE Microwave and Wireless Components Letters.

[5] A. T. Kalghatgi,et al. A Compact Branch Line Coupler Using Defected Ground Structure , 2008 .

[6] Jun-Bo Jiang,et al. Design of a Novel Compact Power Divider with Harmonic Suppression , 2008 .

[7] J. Malherbe,et al. Double resonant stub bandstop filter with pseudo-elliptic response , 2010 .

[8] J. Wang,et al. Compact Microstrip Ring Branch-Line Coupler with Harmonic Suppression , 2009 .

[9] Chao-Wei Wang,et al. A New Planar Artificial Transmission Line and Its Applications to a Miniaturized Butler Matrix , 2007, IEEE Transactions on Microwave Theory and Techniques.

[10] Kai Chang,et al. Compact second harmonic-suppressed bandstop and bandpass filters using open stubs , 2006, IEEE Transactions on Microwave Theory and Techniques.