An Analysis and Design Method for Wide Range Reconfigurable Filter Bank Using Parallel Inductive Switch Network

In this brief, an analysis and design method for wide range reconfigurable filter bank using parallel inductive switch network (PISN) is proposed. The proposed lumped element filter bank consists of three standalone reconfigurable filters which are directly connected together to the common input/output ports without using series single-pole triple-throw (SP3T) RF switches. Instead, inductive PIN diodes are placed parallel to resonators for switching between three frequency bands. An equivalent and iterative method are proposed to analyze and eliminate impedance loading effects between multiple filter channels for the first time. To verify the proposed design and analysis, a reconfigurable bandpass filter bank was designed and fabricated. The measurement shows that a wide frequency tuning range (FTR) of 94–417 MHz (more than 2 octaves) with less than 5 dB insertion loss and more than 40 dB of suppression in adjacent bands is achieved. Detailed theory and measurement are given with good agreement.