This thesis discusses the design and development of various prototype microwave and millimeter-wave components on multilayer liquid crystal polymer (LCP) technology. The fundamental objective of this work is to understand LCP’s electrical performance up to millimeter-wave frequencies through the implementation of different prototype components and assess its suitability to function as a low-cost next-generation organic platform for 3-D system-on-a-package (SoP) based radio-frequency (RF) applications.
The first section of research focuses on the development of dual-polarization/dual-frequency patch antenna arrays on multilayer LCP technology. The design and fabrication methodology of the arrays using two different substrate configurations are presented. Measurements of scattering parameters and far-field radiation patterns are included together with efficiency calculations, illustrating the advantages of using LCP for antenna applications.
The flexibility and mechanical stability of the multilayer substrate have been demon-strated, making the arrays suitable for space deployment in remote sensing applications. To achieve real-time polarization reconfigurability, micro-electro-mechanical-system (MEMS) swicthes have been integrated with the developed antenna arrays. The performance of these MEMS-integrated arrays are also presented.
Next, we report on the development of several prototype low-pass and band-pass filters on LCP covering a wide range of frequency bands to characterize the electrical performance of LCP in those frequency ranges. Compact, planar, and via-less low-pass filters have been designed using the image parameter method and realized using a semi-lumped approach.
The design methodology is described. Full wave simulations validated with measurement results are presented. In addition, band-pass filters, designed using coupled resonator theory, have been implemented on both single and multilayer LCP technology. A wide variety of filters with different physical and functional characteristics have been developed. The developed filters can be classified based on the filter type (low-pass/band-pass), the resonators used single-mode/dual-mode), the response characteristics (symmetric/asymmetric), and the structure of the filter (modular/non-modular).
Finally, examples of integrated systems operating in the X-b and and V-band are presented. This part of the research involves the design and development of duplexers, radiating elements, and their integration. The duplexers themselves are realized by integrating a set of band-pass filters and matching networks. The synthesis and design techniques established in the earlier chapters were utilized for this purpose.
The X-band system involves open-loop resonators, wide-slot antennas, and a 3-D stack-up, with emphasis on compactness. The V-band system involves open-loop resonators, and patch antennas, implemented on a single-layer technology, with emphasis on electrical performance. Characterization of the individual components, and of the integrated system are included.
This research has resulted in a thorough understanding of LCP’s electrical performance and its multilayer lamination capabilities pertaining to its functioning as a material platform for integrated microwave systems. Novel prototype filters and radiating elements that can take advantage of such multilayer capabilities have been developed.
Author: Ramanan Bairavasubramanian