Analysis of Parasitic Effects on Capacitor-Loaded Broadside-Coupled Split-Ring Resonator RF Filters

Radio-Frequency (RF) filters are one of the key components in the front-end of wireless transceivers that can be miniaturized in order to develop cost and power efficient reconfigurable mobile terminals as those required in next generations (5G/6G) of telecom systems. However, several factors need to be investigated in order to implement multi-standard/multi-mode devices in practice. One of the critical limitations is the deviations of basic performance metrics due to fabrication process variations and effect of parasitic circuit elements. In this context, a parametric analysis on a miniaturized capacitor-loaded broadside-coupled split-ring-resonator filter in sub-6GHz band is presented in this paper. Physical and parasitic effects like substrate thickness, capacitor equivalent series resistance and capacitance variation are analyzed against the filter performance. The effect of each of these parameters on the performance of RF filters is shown such that the solutions for these effects can be considered during mass manufacturing.