Novel compact wideband differential reflective phase shifters with wide range of phase application

Abstract

This paper presents wideband compact differential reflective phase shifters based on the double layer slot-coupled coupler configuration. These novel phase shifters arrangement consists of a 3-dB hybrid coupler with the coupled and transmission ports terminated with elliptically shaped microstrip loads. By altering the ports termination of the coupler, phase shifters propose differential phase ranging from −90° to +90° over 1.2–6 GHz (137%) frequency band. To achieve different range of phase performance, the proper reactance is calculated at the outputs of coupler. These reactances are transformed to the elliptical-shaped microstrip load with various dimensions for every phase shifter. The calculation and simulations results show that the developed circuits provide ±30°, ±45°, ±60° and ±90° differential phase shifts with deviation less than 2.1°. The achieved return loss is better than 10dB as well as insertion loss is less than 1dB. The simulated phase shifters including reference line occupy maximum an area of 25 mm × 50 mm (0.14 λ × 0.28 λ). Simulated results demonstrate that the proposed phase shifters are well suited for use in GPS/DCS/PCS/UMTS/WiBro/ Bluetooth/S-DMB/ WiMax/WLAN frequency bands.