Q-band 4-state phase shifter in planar technology: Circuit design and performance analysis

A 30% bandwidthphase shifter with four phase states is designed to be integrated in aradio astronomy receiver. The circuit has two 90 ° out-of-phasemicrowave phase-shifting branches which are combined by Wilkinson power dividers. Each branch is composed of a 180 °phase shifter and aband-pass filter. The 180 °phase shifter is made of cascaded hybrid rings withmicrowave PIN diodes as switchingdevices. The 90 ° phase shift is achieved with the twoband-pass filters. Experimental characterization has shown significant results, with average phase shift values of −90.7°, −181.7°, and 88.5° within the operation band, 35–47 GHz, and mean insertion loss of 7.4 dB. The performance of its integration in a polarimetric receiver forradio astronomy isanalyzed, which validates the use of the presentedphase shifter in such type of receiver.

Source: Review of Scientific Instruments - September 29, 2016 Category: Physics Authors: E. Villa, J. Cagigas, B. Aja, L. de la Fuente and E. Artal Source Type: research