Raul de Lacerda

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We present in this survey new technologies proposed for the evolution of the aeronautical communication infrastructure. Motivated by studies that estimate a growth of the air traffic flow, a joint Euro-American project was launched in 2004 to provide solutions adapted to the future aeronautical scenario (air-air communication, traffic optimization...). This(More)
This work presents some initial results concerning the MIMO channel capacity of real wireless channels in the UMTS-TDD band using the Eurecom MIMO Openair Sounder (EMOS). This paper describes the necessary steps to estimate in real-time the wireless MIMO environment, offering the possibility to identify reliable MIMO channels as well as instantaneous(More)
—General and commercial aviation authorities have been using amplitude modulation communication systems for more than 70 years. Due to the great increase of air traffic during the last years, the VHF band tends towards saturation, whereas the aeronautical community faces new requirements: data rate, spectral efficiency and network capacity (maximum number(More)
— The parametric estimation of Multiple-Input Multiple-Output (MIMO) channels is an important step towards the space-time characterization of the radio channel as well as for the design of efficient space-time signaling techniques. In this paper, we address the problem of multipath parameter estimation for frequency-selective block-fading MIMO channels by(More)
Keywords: Heterogeneous networks Cross-system diversity Soft handover Power allocation Random matrix theory Multiple access channel CDMA MIMO OFDM a b s t r a c t This paper investigates the situation where a group of terminals can be simultaneously connected to several base stations, using distinct technologies on non-overlapping frequency bands. We(More)
— In wireless communication, interference between two radio systems may occur when they operate at close frequency bands, sharing the same environment at the same time. Such systems coexist if both of them perform correctly in the presence of the other. To ensure their coexistence, Electromagnetic Compatibility (EMC) is used to specify rules within(More)
—In the last decade, the aeronautical authorities expressed their need to develop a new system for aeronautical radiocommunications. The L-band Digital Aeronautical Communication System (L-DACS) is the part of the future system that will be operating in a part of the aeronautical L-band (960−1164 M Hz), already occupied by a large number of radio-frequency(More)
Energy Efficiency (EE) has become one of the main challenges for the development of wireless communication systems. Thus, many researchers are investigating new solutions to save power. For this reason, in this paper we apply a method based on modulation and coding scheme (MCS) for multiband orthogonal frequency division multiplexing (MB-OFDM) ultra(More)
In this contribution, we describe the potential of SDR4all (Software Defined Radio for all) to solve the bottlenecks and reduce the innovation cycle related to the design and implementation of flexible radio algorithms. SDR4all is a programmable software tool with radio cards for wireless researchers, students and engineers. It enables to implement in(More)