Vol. 34

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A New Broadband Microstrip Quadrature Hybrid with Very Flat Phase Response

By Adelaide Ladu and Giampaolo Pisano
Progress In Electromagnetics Research C, Vol. 34, 227-237, 2013


A new broadband microstrip branch-line quadrature hybrid with very flat phase response is presented. The device is made by cascading four branch-line couplers with arbitrary power division. The novel design is based on the microstrip transposition of a broadband waveguide polariser [4]. Across a 32% bandwidth centred at 9.3 GHz, the RL and the IL are respectively -15 dB and -3 dB/-4 dB; the phase difference is very flat, i.e. 90°±1.5°.


Adelaide Ladu and Giampaolo Pisano, "A New Broadband Microstrip Quadrature Hybrid with Very Flat Phase Response," Progress In Electromagnetics Research C, Vol. 34, 227-237, 2013.


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