The investigation of reconfigurable SIW filter using varactor diodes

This paper introduces a novel reconfigurable SIW filter for 4G applications by using varactor diodes. This SIW filter consists of two floating islands with two via holes that connected with two varactor diodes. This method allows designing SIW filter with the tunable centre frequency with a constant absolute bandwidth. The filter is designed through the simulation on a standard printed circuit board technology. The SIW filter at 2.097 GHz shows an insertion loss of 1.87 dB and 3 dB bandwidth of 163.39 MHz. SIW filter is used to obtain a good performance that suitable for integration with any reconfigurable planar structure. This investigation provides an alternative solution for reconfigurable SIW filter, particularly in 4G communication systems.