Physical Impairment Modelling in Flexible Optical Node Architectures
One major goal in this project is to develop an analytical formulation,as well as a stochastic Monte-Carlo (MC) simulator, that allow us to study in a rigorous way the impact of in-band crosstalk, both incoherent and coherent, originated in CDC ROADMs in the performance of flexible grid networks, considering 16-QAM and 64-QAM 400 Gbps signals.On a network-side perspective, the emergence of modulation formats with higher-order constellations and, consequently, with stricter performance margins has increased the importance of physical impairment awareness in the network planning process. Thus, it is essential to incorporate the effects of in-band crosstalk, along with other effects, in an impairment-aware routing and spectrum assignment (RSA) framework. This framework should be able to efficiently provision paths and spectrum for superchannels based on M-QAM carriers in a CDC-ROADM network, while using the physical model as a performance validation tool for candidate optical paths
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Remote Piloted Semi-Autonomous Aerial Surveillance System Using Terrestrial Wireless Networks
The main objective of SAAS is to develop an UAV remote control system that is mostly independent of a specific vehicle model or design and that makes use of the available terrestrial wireless networks. The individual challenges and objectives to be addressed are:• Real-Time Video Transmission and Control using Terrestrial Wireless Networks: Investigate the possibility of transmitting real time video and control commands with adequate quality for a pilot to control and make decisions on the vehicle course using the available radio networks (GSM, UMTS, HSDPA, Wi-Fi, LTE).• Semi-autonomous Flight Control: Develop autonomous control capabilities for the aircraft to perform its self-rescue in the case of loss of radio connection and that can also allow a reduced piloting workload.• Remote Visualization and Control Application: Implement an application for tablet PCs that enables the visualization of the video captured by the aircraft cameras together with other telemetry information and allows the pilot to command the aircraft (either using the touchscreen, the accelerometers or an additional attached joystick).• Prototype Implementation and Flight Tests: Implement a prototype using a small rotary-wing aircraft (possibly a tricopter/quadcopter) and evaluate the performance in terms of video reception, control, and autonomy capability.
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LTE-Advanced Enhancements using Femtocells
The project will take LTE-Advanced as a reference and will explore possible enhancements to the support of femtocells. It will use mechanisms to reduce the interference-limited transmission with full frequency reuse. These include CQI, QoS- and interference- aware scheduling and RRM with user-grouping, coordinated RRM, exploiting the spatial degrees of freedoms from multi-antenna systems and OFDMA through MIMO and beam forming techniques, active interference management and CoMP transmission, as well as carrier aggregation for multi-band transmission.New technologies like aggregate carriers and cooperative multi antennas antenna systems as part of LTE-Advanced systems will be evaluated with respect to their ability to enhance the performance of networked femtocells based on LTE-A. The availability of Positioning information, can help provide the network with information on the terminal positions and, with this, to adapt the transmission scheme to the terminal avoiding worst channel conditions.At the network layer, considerable research and development has been recently focused on the use of small cellular base stations. However, those cells have only been considered as mere extensions to cellular networks, allowing the enlargement of service coverage. The use of these small cells, mostly deployed by consumers, has not yet been fully explored. There are many services and protocols in the network that could benefit on the scattering of this kind of cell deployment. This project will exploit the opportunities that small cells will bring to improvement on the network architecture. The aim is to a achieve a much richer small cell, that will provide better support for several services and protocols that could take advantage on a distributed architecture and/or context ware and localized information.Femtocells can have many benefits for both operators and users. From an operational or deployment perspective however their integration into the network is quite hard. From the ...
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