Diplexer Embedded with Crisped S-shaped Complementary Split Ring Resonators for LTE Band Application

In this paper, a novel structure of diplexer is designed based on Substrate Integrated Wave guide (SIW) technology and S-shaped complementary split ring resonator  to operate in LTE1.3 GHz  -2.1 GHz band. A miniaturized and compact SIW diplexer implemented by Crisped S-shaped Complementary Split Ring operated in a waveguide format is proposed and presented. In design process, firstly, the filters corresponding to each of the bands is designed in simulator, then by using S-parameter of each filter the T-shaped structure dimensions of the input feeding diplexer is achieved and optimized. It is deduced from measurement results of diplexer that input and output impedance matching in the respective bands, transmission losses are1dB and 2dB for 1.3 GHz and 2.1 GHz respectively. The isolation between output ports is better than 30dB. Finally the proposed structure reflects the performance is highly desirable. This structure illustrates advantages in terms of the small size, low loss, high isolation, easy realization and integration with other planar circuits.