volume | PIER Journals

Abstract

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°.

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12. , , , Ansoft High Frequency Structure Simulator, www.ansoft.com.

13. , , , Trackwise, Unit 4B Delta Drive, Tewkesbury Business Park, Tewkesbury, Gloucestershire GL20 8HB, UK.

Dr. Adelaide Ladu

Dr. Giampaolo Pisano