Dual-Composite Right-Left Handed Transmission Lines for the Design of Compact Diplexers

In this study, the use of dual-composite right-left-handed (D-CRLH) transmission lines is proposed for the design of diplexers. The D-CRLH diplexers present advantages over conventional diplexers such as smaller size (especially in the ultra high frequency band). The design procedure and the design equations are presented in this paper. The non-linear phase response of a D-CRLH transmission line has been used to design diplexers at any arbitrary frequencies. Finally, two diplexers have been designed and manufactured: one for quite near frequencies and the other for further ones. The simulation results show good agreement with the measurements. A sensitivity analysis has been provided to show the robustness of this kind of circuits

New frontiers in microwave metamaterials : magnetic-free non-reciprocal devices based on angular-momentum-biasing and negative-index metawaveguides

In this work, metamaterial concepts are applied to improve the design and realization of microwave components of a new generation. Conventional radiation sources, despite the mature and efficient development over the past century, maintain fundamental limitations. Slow-wave structures, such as backward-wave oscillators and traveling-wave tubes, function on the order of several operational wavelengths, leading to bulky architectures. Cherenkov radiation-based detectors are constrained to forward propagation, where the detection or diagnostic scheme may be damaged by energetic particles. Metamaterial concepts, specifically negative-index structures, provide new opportunities for these applications. In this context, we developed a detailed design of a negative-index metamaterial conducive to microwave generation. We experimentally validated a negative-index waveguide based on patterned plates of complementary split ring resonators. The design is conducive to interaction between particles and waves; it maintains a scalable negative-index band along with a longitudinal electric field component for particle interaction. The sub-wavelength resonant nature of the metamaterial allows for a compact design. In a different field of research, there is also significant need to squeeze the dimensions of microwave components. We have developed magnet-less, non-reciprocal, microwave circulators based on angular-momentum-biasing, which allow the realization of non-reciprocal devices that do not require magnets, and therefore lead to cheaper, lighter and significantly smaller devices. Angular-momentum-biasing, theoretically proposed recently in our research group, effectively mimics the collective alignment of electron spins seen in a ferromagnetic medium under a magnetic bias. Through spatiotemporal modulation, one can generate electrical rotation, leading to strong nonreciprocal response without magnetism. We have experimentally proven the theory on lumped element circulators and proposed transmission-line variations, providing over 50 dB of isolation in a range of frequency bands. This method provides efficient, easily tunable, fully integrable, compact devices that may revolutionize the future of integrated components. We have developed rigorous design principles that not only provide guidance for designs based on desired performance metrics, but also proves the passive nature of the concept. Furthermore, we have crafted mechanisms to enhance the bandwidth performance and improve linearity.Electrical and Computer Engineerin

Microwave integrated circuit broadband filters and contiguous multiplexers

A novel design and construction technique for Microwave Integrated Circuit broadband filters and a contiguous multiplexer is presented together-with experimental results on a number of devices. The multiplexer is formed from a cascade of diplexers each containing a highpass and lowpass filter. Basedon the generalised Chebyshev prototype, selective low loss microwave filters for these diplexers are designed having new suspended substrate configurations. Octave bandwidths are achieved for the high pass channels. The contiguous multiplexer built has three outputs 4 - 8 GHz, 8 - 12 GHz and 12 - 18 GHz and is constructed on a single substrate approximately 2" x 1 ¼”. Experimental results show each channel has low pass band loss and highly selective responses at the bandedges and the multiplexer will meet the normal environmental conditions. Also, due to the printed circuit realisation, a high degree of population tracking can be readily achieved. Detailed computer analysis of the devices is presented and results are in very close agreement with the experimental results. Suitable constructional techniques are developed so the final multiplexer could be manufactured on a commercial basis

Dispositivos ópticos baseados na plataforma de fabricação com laser por escrita direta para aplicações em biossensado

Orientador: Lucas Heitzmann GabrielliTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de ComputaçãoResumo: Um dos principais desafios no século XXI, é a necessidade de detectar e controlar os elementos biológicos relacionados com a sauúde humana e o meio ambiente... O resumo poderá ser visualizado no texto completo da tese digitalAbstract: The need to detect and control biological elements related to human health and the environment is one of the main challenges of the 21st century... The abstract is available with the full electronic documentDoutoradoTelecomunicações e TelemáticaDoutor em Engenharia Elétrica200370/2014CNPQCAPE

Multiple Order Dual-Band Active Ring Filters with Composite Right/Left Handed Cells

In this paper, a novel dual-band active filter topology is presented. The non-linear phase response of a composite right/left-handed cell is used to achieve the desired dual-band performance. Additionally, the proposed structure based on coupled ring resonators yields a very compact solution in which high-order implementations can be easily obtained by cascading multiple rings. The theoretical principles of this type of filters are analyzed in detail. Finally, three prototypes based on first-, second- and third-order structures validate the feasibility of this type of filters. Good agreement between simulations and measurements has been achieved