A NRI-TL Metamaterial Based Dual-band Phase Shifter

This paper presents a new reconfigurable phase-shifter based upon the theory of negative refractive index transmission line (NRI-TL) metamaterial unit cells. The lumped elements are inter-switchable among them with biased polarities of two pin diodes. The design layout of the proposed phase-shifter has been studied in Keysight ADS and consequently modeled using the equivalent microstrip configuration in CST Microwave Studio solver. A compact parallel phase-shifter has been designed on the RO4003C substrate covering an area of 46.40 mm × 45 mm. The dual-band characteristics has been realized in two distinct frequency bands of 1.26 GHz and 2.4 GHz enhancing its efficiency and operating range over the respective bandwidths of 120 MHz and 200 MHz. A nearly constant of average phase differences of 110° and 60° have been achieved in the respective bands of operation. The slope of the differential phase shift has been achieved close to 5° making this device a unique one. The high return losses in the two bands of operation result in better performance of the phase-shifter. The proposed prototype can find applications in phased-array antennas, military applications and aerospace industries.