DC and radio-frequency transmission characteristics of double-walled carbon nanotubes-based ink

In this paper, double-walled carbon nanotubes (DWNTs) network layers were patterned using inkjet transfer printing. The remarkable conductive characteristics of carbon nanotubes (CNTs) are considered as promising candidates for transmission line as well as microelectronic interconnects of an arbitrary pattern. In this work, the DWNTs were prepared by the catalytic chemical vapor deposition process, oxidized and dispersed in ethylene glycol solution. The DWNTs networks were deposited between electrodes contact and then characterized at DC through current-voltage measurements, low frequency, and high frequency by scattering parameters measurements from 40 MHz up to 40 GHz through a vector network analyzer. By varying the number of inkjet overwrites, the results confirm that the DC resistance of DWNTs networks can be varied according to their number and that furthermore the networks preserve ohmic characteristics up to 100 MHz. The microwave transmission parameters were obtained from the measured S-parameter data. An algorithm is developed to calculate the propagation constant "γ", attenuation constant "α" in order to show the frequency dependence of the equivalent resistance of DWNTs networks, which decreases with increasing frequency

Review of LTCC Technology for Millimeter Waves and Photonics

VTT Technical Research Centre of Finland Ltd. has developed and utilized Low Temperature Co-fired Ceramic (LTCC) technology for about 25 years. This paper presents our activities related to photonics and millimetre-waves, including also a relevant literature survey. First a short summary of the technology is given. Especially, the unique features of LTCC technology are described in more details. In addition, several examples have been given to show the validity of LTCC technology in these high-performance fields

Advanced Filter Solutions for High-performance Millimetre and Submillimetre-wave Systems

This thesis is devoted to the investigation of advanced filter design solutions for high-performance millimetre and submillimetre-wave systems. Each of the proposed design solutions are enabled using waveguide-based technologies with the aim of advancing future generations of satellite communications, radar, and remote sensing. As trends for frequency allocations move to higher and higher frequency bands, engineers are faced with increasingly complex challenges such as the degradation of component performance, the inability to correctively tune the performance, or scenarios that all together make circuits infeasible. In light of these challenges, this work seeks to advance the current literature on filter design and proposes many unique design solutions for overcoming manufacturing and accuracy limitations, reducing the transmission losses, and reducing the overall design complexity. Each of the proposed filter solutions that are presented in this thesis are based on either a novel structural design or a novel technology. Each of the proposed designs are presented with functional prototypes as a means of verifying the theory. In the majority of cases, prototypes have been manufactured using high-precision computer numerical control (CNC) milling, and in several articles, exploratory activities with the use of alternative technologies such as stereolithography (SLA) 3D-printing and deep-reactive ion etching (DRIE) are presented. Prior to the presentation of the filter designs, an overview on the design and synthesis of millimetre-wave filters and diplexers is provided and serves as a foundation for the coupling matrix descriptions of symmetric and asymmetric resonator designs throughout this work