Health-care delivery in developing countries has many challenges because they do not have enough resources for meeting the healthcare needs and they lack testing lab infras- tructures in communities. It has been proven that Point-Of-Care (POC) testing can be considered as one of the ways to resolve the crisis in healthcare delivery in these com- munities. The POC testing is a mission critical processes in which the patient conduct tests outside of laboratory environment and it needs a secure communication system of architecture support which the research refers as POCT system Almost every ten years there will be a new radio access technology (RAT) is released in the wireless communication system evolution which is primarily driven by the 3GPP standards organisation. It is challenging to develop a predictable communication sys- tem in an environment of frequent changes originated by the 3GPP and the wireless operators. The scalable and expandable network architecture is needed for cost-effective network management, deployment and operation of the POC devices. Security mecha- nisms are necessary to address the specific threats associated with POCT system. Se- curity mechanisms are necessary to address the specific threats associated with POCT system. The POCT system communication must provide secure storage and secure com- munication to maintain patient data privacy and security. The Federal Drug Admin- istration (FDA) reports the leading causes of defects and system failures in medical devices are caused by gaps between the requirements, implementation and testing. The research was conducted, and technical research contributions are made to resolve the issues and challenges related to the POCT system. A communication protocol implemented at the application level, independent of radio access technologies. A new methodology was created by combining Easy Approach to Requirement Specifications (EARS) methodology and Use Case Maps (UCM) model which is a new approach and it addresses the concerns raised by the FDA. Secure cloud architecture was created which is a new way of data storage and security algorithms models were designed to address the security threats in the POCT system. The security algorithms, secure cloud architecture and the communication protocol coexist together to provide Radio access technology Independent Secure and Expandable (RISE) POCT system. These are the contributions to new knowledge that came out of the research. The research was conducted with a team of experts who are the subject matter experts in the areas such as microfluidics, bio-medical, mechanical engineering and medicine.

Electromagnetic waves in the terahertz spectral range have gained significant research focus due to their applications in various fields of science. To effectively generate and integrate terahertz waves in systems, appropriate waveguide design is critical. Conventionally waveguides have been used to control the propagation of electromagnetic waves. A waveguide with low loss and dispersion is always preferred. But achieving these characteristics is quite challenging especially if operating in the terahertz spectral range. There are inherent material and geometric limitations that exist for terahertz waveguides. It is therefore important to optimize the design to enable their use in applications efficiently. This thesis investigates the characteristics of three primary terahertz waveguides based on the underlying theory and results obtained from simulations. The three waveguides are parallel-plate waveguides, two-wire waveguides, and coplanar striplines. The work in this thesis mostly focuses on coplanar striplines, optimal for building a highly efficient commercial and portable terahertz system-on-chip (TSOC). The contribution of the thesis is around the use of different types of passive components mounted on a thin commercial Silicon Nitride membrane. A bias tee is introduced which is a combination of interdigitated electrodes and a meander inductor. The length of the interdigitated electrodes and the gap between them are 55 um and 5 um, respectively. The S21 parameter for this structure ranges from -24 dB/mm at near-zero frequencies to -0.8 dB/mm at 1 THz. This indicates that the designed bias tee can appropriately block low frequencies. Split-ring resonators are also used to act as band-stop filters. The resonant frequency of the resonator depends on the radii of the split-rings. In the optimized design, the internal radius of the outer ring is 25 um and the external radius of the inner ring is 20 um. This results in a narrowband band-stop filter with its resonant frequency centered at 701 GHz. The optimized final TSOC design discussed in this work uses these passive components placed on the Silicon Nitride membrane and is shown to have a total loss that is 3 dB/mm less than any of the previous work for terahertz frequencies. / Graduate

Techn. Univ., Diss.--Ilmenau, 2006.