Orange S.A.

About: Orange S.A. is a company organization based out in Paris, France. It is known for research contribution in the topics: Terminal (electronics) & Signal. The organization has 6735 authors who have published 9190 publications receiving 156440 citations. The organization is also known as: Orange SA & France Télécom.

A novel approach to achieve unequal error protection for video transmission over 3G wireless networks

Abstract: In this paper, we present a novel unequal error protection technique that enhances the video transmission quality over wireless networks. The case of application considered is a UMTS/TDD transmission system for H263 compressed and turbo-coded video sequences. The overall redundancy added to the compressed stream is non-uniformly distributed between the succeeding video frames in order to minimize the mean distortion over the transmitted sequence. The repartition of the redundancy on the video stream is optimized using an analytical approach which aims to alleviate the error propagation along the sequence. Different puncturing patterns of the rate 1 3 turbo-coder were considered in our simulations. The results obtained here are compared to those with a classical equal error protection scheme. We demonstrate that the gain in the system performances can reach 1.5 dB (in terms of the mean peak signal-to-noise ratio) without any significant increase in the transmission rate or the receiver complexity.

Ultra-Broadband Wireless Home Network Based on 60-GHz WPAN Cells Interconnected via RoF

Abstract: In this paper, we first identify the key requirements for the deployment of a 1-Gb/s ultra-broadband home area network (UBB-HAN). Second, we propose an architecture based on a transparent optical backbone feeding local access points. Third, we underline the role of the IEEE802.15.3c pre-standard to provide a suitable radio interface for the UBB-HAN and demonstrate the technical feasibility of the concept using radio over fiber (RoF). More than 1-Gb/s transmission is demonstrated for 50-m optical antenna remoting using radio-over-fiber plus 15-m radio transmission.

Frequency-Domain Block Turbo-Equalization for Single-Carrier Transmission Over MIMO Broadband Wireless Channel

Abstract: This paper presents a new class of block turbo-equalizers for single-carrier transmission over multiple-input multiple-output (MIMO) broadband wireless channels. The key underlying idea consists in equalizing (nonoverlapping) groups of symbols and detecting their individual space-time components in a disjoint and iterative fashion. This functional split naturally induces new design options that have been accurately listed and described, i.e., choice of distinct criteria for intergroup interference (IGI) equalization and intragroup components detection, yielding hybrid structures, multiple iterative loops, and related scheduling variants. Selected algorithms in the proposed class are compared in terms of performance under various transmission scenarios. For all of them, minimum mean square error IGI equalization certainly occupies a central role (at least for the first iteration) and may be identified as the computational bottleneck. Fortunately, block spread transmission together with cyclic prefix operations make the channel matrix block circulant, thus allowing low-complexity inversion in the Fourier domain

Efficient Wavelet Packet Modulation for Wireless Communication

Abstract: Based on the good time-frequency localization of the pulse shaping, it is possible to build a multicarrier modulation that reduces both narrowband interferences and multipath channel interferences. In this paper, the given solution is based on wavelet theory: wavelet packet based multicarrier modulation is introduced and compared to the useful orthogonal frequency domain multiplexing (OFDM) modulation in a wireless environment with narrowband interferences and multipath channel interferences. Simulations show that the use of wavelet is more robust to narrowband interferences than the OFDM modulation. For multi- path transmission, simulations show that the use of complex wavelet outperforms the use of real one and outperforms the OFDM modulation when the cyclic prefix technique is not used.

A new global time-domain electromagnetic simulator of microwave circuits including lumped elements based on finite-element method

Abstract: This paper proposes an extension of the finite-element time-domain method for the global electromagnetic analysis of complex inhomogeneous microwave distributed circuits, containing linear or nonlinear lumped elements. This technique combines Maxwell's equations and circuit equations, directly using SPICE software for the lumped part. Its validation is performed through the study of a strongly coupled two-element active antenna.