Ciência-IUL    Autores    João Carlos Marques Silva    Projetos de Investigação
Projetos de Investigação
Enhanced Underwater Acoustic Receiver Design for MIMO Communications
The underwater world offers an immense space with an enormous potential, especially for a country as is Portugal that has one of the biggest marine zones in Europe (Exclusive Economic Zone, the 3º largest in Europe and 11º largest in the world). A fundamental part for withdrawing the full potential of this natural resource is to solve the problem of high-bandwidth underwater communications. This project aims to develop signal processing schemes that will enable for high bandwidth underwater acoustic (UWA) communications using aggregates of sources and hydrophones (Multiple Input, Multiple Output - MIMO) between mobile emitters and receivers.In radio communications, MIMO systems allows for considerable gains in the transmitted throughput and reliability, what has recently made several research groups to consider them for UWA. However, the propagation channel in UAC has characteristics substantially different than that of radio channels; since it has a high variability in both time and frequency (i.e., the channel is doubly selective). Besides that, the noise presents impulsive characteristics, for which the normal Gaussian model is inadequate. So being, the use of techniques for the normal radio channel without specific modifications would give rise to high performance degradation in UAC. This being, the main purpose of this project is to develop and assess the performance of transmission techniques for MIMO-UWA systems. The project will begin by selecting relatively simple channel models to account for the doubly selective specificities of the doubly selective UWA channel model. Adequate models to characterize the impulsive noise specifications of the channel will also be selected, in order to permit adequate analytical processing. Afterwards, special transmission techniques specially designed for MIMO-UWA will be developed. These techniques will be based on MIMO-OFDM (Orthogonal Frequency Division Multiplex) and MIMO SC-FDE (Single Carrier- Frequency Domain Equaliz...
Informação do Projeto
2014-03-01
2015-02-01
Parceiros do Projeto
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.
Informação do Projeto
2012-03-01
2014-04-01
Parceiros do Projeto
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 ...
Informação do Projeto
2012-03-01
2014-12-31
Parceiros do Projeto
Comparison of WiMAX and LTE on a Personal Cell Scenario for the Provision of Multimedia Broadcast/Multicast Services
The main goal of COILS is the design and evaluation of efficient methods for the provision of broadband services and applications based on MBMS to groups of mobile users located mainly in Personal Cells. The use of MBMS over Personal Cells will support the efficient use of radio and network resources, while also providing rich context information to applications and services. Merging these two frameworks promises enhanced multimedia application provisioning, benefiting end users and operators alike. The technologies investigated during the course of the project will generate considerable novel intellectual property that will become the property of IT.
Informação do Projeto
2008-12-01
2010-11-01
Parceiros do Projeto
Advanced MBMS for the Future Mobile World
New RAN technologies and IMS to support future MBMS based on Long term Evolution of 3GPP
Informação do Projeto
2006-03-01
2008-04-01
Parceiros do Projeto
Satellite Ground Station for Study and Development of Radio Communications
This project aims at building a satellite ground station at the Ku band that can be remotely controlled and accessed through a dedicated server to all authorized users using a simple web browser connected to the internet anywhere in the world. Authorized users can request and collect data (telemetry, images, etc) from its database for post-processing. This equipment can be used for a great variety of experiments not previously possible at this location and can be an important factor to increase the cooperation amongst national and international researchers and institutions, namely with ESA. Its location and features are unique and can be of strategic importance for the development of national research and industry in this field.
Informação do Projeto
2006-01-01
2006-12-31
Parceiros do Projeto
Broadcasting and Multicasting Over Enhanced UMTS Mobile Broadband Networks
B-BONE main objective is to further enhance UMTS capacity, transmission rates, RAN and Core network functionalities, considering both FDD and TDD modes, so as to accommodate digital broadcasting/multicasting (multimedia) type services.
Informação do Projeto
2004-02-01
2006-06-30
Parceiros do Projeto
Simulation of Enhanced UMTS Access and Core Networks
SEACORN provides a fundamental contribution to the evaluation and development of Enhanced UMTS networks. It covers several aspects starting from the definition and characterisation of services and user profiles, including the modelling of the user's behaviour with respect to mobility and multimedia activity, and finally considering the optimisation of the networks from both points of views: the operator's and manufacturer's view of limiting the infrastructure and maintenance costs and the user's view of being provided with high quality services
Informação do Projeto
2002-03-01
2004-02-28
Parceiros do Projeto