Design and implementation of low loss and compact microstrip triplexer using CSRR loaded coupled lines

In this paper, a passive S-band triplexer using complementary split ring resonators (CSRRs) etched on the ground plane and interdigital capacitor in the upper metal is presented. The proposed structure is designed with three output ports operating at three distinct center frequencies of 1.4 GHz, 1.8 GHz and 3.2 GHz, which are suitable for multiband receivers working at LTE bands. The proposed triplexer is simulated, fabricated and measured. Simulation and experimental results of scattering parameters are in good agreement. This structure comprises these specifications: insertion loss less than 2 dB, isolation between channels approximately 20 dB and about 5% fractional bandwidth regarding VSWR < 1.5. The proposed triplexers dimensions are 0.07 lambda(0) x 0.2 lambda(0). (C) 2019 Elsevier GmbH. All rights reserved.