Multilayer Broadside-Coupled Dispersive Delay Structures for Analog Signal Processing

A compact multilayer non-commensurate C-section dispersive delay structure (DDS) is proposed for analog signal processing (ASP) applications. In contrast to a previously reported C-section DDS, which was uniplanar and used edge-coupled C-sections, this DDS is based on broadside-coupled C-sections, and hence achieves a much larger ratio of group delay swing to frequency bandwidth, leading to higher ASP resolution. Moreover, it is much more compact, while maintaining acceptable insertion loss. After a parametric characterization of a mono-block commensurate multilayer DDS, with varied strip widths, two multiblock non-commensurate DDSs with linear group delay slopes are demonstrated by full-wave simulation and experimental low-temperature co-fired ceramics results. The proposed DDS exhibits a significant footprint reduction factor of around 7 compared to its uniplanar edge-coupled counterpart.