REFLECTIVE PHASE SHIFTER BASED ON WIDEBAND MULTI-SECTION HYBRID COUPLER IN SLOT-COUPLED STRUCTURE

摘要

This article presents a novel reflective phase shifter based on wideband multi-section 3-dB hybrid coupler in slot-coupled structure. By terminating coupled and transmission ports of coupler with rectangular microstrip loads, reflective phase shifter is achieved. It designed on multilayer Rogers RO4003C substrate. The configuration consists of elliptically shaped transmission line and the combination of rectangular and elliptical shaped slots on the ground plane. To improve characteristics of the designed coupler especially in lower frequency band, multi-section transmission line and altering shape of the slot on ground is proposed. By etching extra rectangular slots on the ground plane the overall size reduction is achieved. Measurement results of the proposed coupler demonstrate coupling of 3 +/- 0.7 dB with 90 degrees +/- 0.6 phase shift over 1-6 GHz (143). The novel reflective phase shifter based on the designed coupler provides phase deviation less than 0.7 degrees on 1.2-4.8 GHz (120). The obtained return loss is better than 10 dB as well as insertion loss is less than 1.2 dB at the frequency band of interest. (C) 2017 Wiley Periodicals, Inc.