Towards 5G: A study of the impact of antenna polarization on statistical channel modeling

The millimetre wave (mmWave) is alleged as an important element invention to respond to the rapid increase in wireless demand for mobile traffic using its huge bandwidth. However, channel modeling remains difficult due to its high dependence on weather conditions and the positioning of the antenna for communication in direct visibility line-of-sight (LOS). Co-polarization and cross-polarization (X-pol) are two main events in the direction of the radiation element for wave transmission; where the wanted direction of wave transmission denotes the co-pol and the orthogonal propagation of the intended direction represents X-pol. This work investigates the effect of the polarization on a statistical channel modeling at 28 GHz, 38 GHz & 73 GHz mmWave channel using NYUSIM Model

State-of-the-art assessment of 5G mmWave communications

Deliverable D2.1 del proyecto 5GWirelessMain objective of the European 5Gwireless project, which is part of the H2020 Marie Slodowska- Curie ITN (Innovative Training Networks) program resides in the training and involvement of young researchers in the elaboration of future mobile communication networks, focusing on innovative wireless technologies, heterogeneous network architectures, new topologies (including ultra-dense deployments), and appropriate tools. The present Document D2.1 is the first deliverable of Work- Package 2 (WP2) that is specifically devoted to the modeling of the millimeter-wave (mmWave) propagation channels, and development of appropriate mmWave beamforming and signal processing techniques. Deliver D2.1 gives a state-of-the-art on the mmWave channel measurement, characterization and modeling; existing antenna array technologies, channel estimation and precoding algorithms; proposed deployment and networking techniques; some performance studies; as well as a review on the evaluation and analysis toolsPostprint (published version

THz Ultra-wideband Passive Devices: Design, Simulation and Characterization

The last decades have seen an increasing interest in the THz research field, leading to a substantial improvement in technology and the emergence of new applications. In particular, the research on radio astronomy instrumentation has pushed millimeter and sub-millimeter technology boundaries and redefined state of the art.\ua0 Nonetheless, the requirements set for the next generation of radio astronomy receivers will demand remarkable technological development, especially in terms of RF and IF bandwidth. Addressing this need, the present licentiate thesis focuses on the design, simulation and characterization of ultra-wideband THz passive devices for the next generation of radio astronomy receivers. As THz receivers mixers are implemented with thin-film technology, waveguide to substrate transitions have a fundamental role in the performance and bandwidth of such systems. The critical requirements for these transitions are a proper impedance matching and the minimization of insertion loss. In this thesis, a waveguide to slotline superconducting transition based on substrateless finlines is proposed. The transition was designed for prospective broadband SIS mixer design in the frequency range 211-375 GHz. The experimental verification at cryogenic temperatures shows a remarkable fractional bandwidth of 55%. Although this transition represents a substantial improvement over existing designs, it is important to note that it transforms a waveguide propagation mode into slotline mode. For the majority of modern SIS mixers, microstrip line topology is the most suitable. Hence, the ongoing development is focused on broadband slotline to microstrip transitions. In this work, a slotline to microstrip transition based on Marchand Balun is designed, simulated and fabricated. The electromagnetic simulations showed promising results, and the cryogenic characterization at 4K is ongoing.For most modern polarization-sensitive THz receivers, 90\ub0 waveguide twists are essential interconnection parts. Since compactness and low insertion loss are critical requirements, single step-twists have emerged as an attractive solution. In this work, a novel compact wideband 90-degree twist for the 140-220 GHz band is presented. Furthermore, the proposed twist has a performance tolerant to small geometry variation, and hence it is especially suited for fabrication by direct milling. The experimental verification shows 44% fractional bandwidth with return loss better than 20 dB over most of the band