Interdigital Multiple Coupled Microstrip DC Blocks

The analysis, design procedure and experimental results for open circuited, interdigital multiple coupled microstrip line structures for applications as wide band DC blocks are presented. As in the case with other microstrip structures, the initial design procedure is formulated by assuming TEM modes of propagation. The final design is then based on the exact computation of the frequency response of the n-line two port (Fig 1) including the effect of coupling between non-adjacent lines and unequal phase velocities of the n normal modes of the system.