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.

Silicon photonics for next generation FDM/FDMA PON

Abstract: Frequency division multiplexing/frequency division multi-access passive optical networks are shown to provide a possible solution in terms of performance, manufacturability and cost to the specification of the second next generation passive optical access systems (NG-PON2). The upstream capacity of a particular implementation is experimentally evaluated, and the implementation of the required optical network unit in silicon photonics is analyzed, as this complementary-metal-oxide-semiconductor-compatible technology is well suited for mass market applications.

Service activation by virtual prepaid card

Abstract: In order to prevent the use of a virtual prepaid card illegitimately acquired and transmitting only one identification code, for example read after the card has been scratched, to a service provision server, a second code is delivered on paying for the card, and the two codes have to be authenticated so that the user-purchaser of the card can subsequently use the service concerned in the server still using only the first code.

Theory and measurement of the angle of arrival and time delay of UHF radiowaves using a ring array

Abstract: The knowledge of directions of arrival (DOA) of waves is fundamental in understanding the physics of the mobile communications wide-band propagation channel. We first present a measurement setup that is able to accurately measure these DOA. It is based on the evaluation of the channel complex impulse response at regularly spaced locations on a circle. We theoretically investigate a new approach for deriving the DOA from this ring array. We then describe an experimental campaign, where such measurements were done on a building rooftop. We show that all the main paths are clearly retrieved and identified and that the ray theory is valid and applicable. The results emphasise the predominant role of UHF-wave specular reflection by walls in an actual urban environment.

Insensitivity results in statistical bandwidth sharing

Abstract: We show that statistical bandwidth sharing performance under an assumption of perfect fairness is insensitive to both the flow size distribution and the flow arrival process, given only that session arrivals are Poisson. Observed self-similarity phenomena at packet and flow levels can be explained by the interaction between high level traffic characteristics and the way link bandwidth is shared. We show in particular that long range dependence in the flow arrival process is due to the heavy-tailed nature of the distribution of the number of flows per session.

Hybrid multiplicative multi-watermarking in DWT domain

Abstract: Multiwatermarking embeds multiple watermarks into the media content imperceptibly. It is regarded as the potential means to protect the media contents' copyright and/or trace illegal redistributors in multi-user environments, e.g., collaborative media content production or layered media content distribution. However, there are still some open issues in designing a good multiwatermarking scheme, including the combination between multiple embedding steps, the combination between multiple watermarks and the security of embedding schemes. In this paper, novel multiwatermarking schemes are proposed, which are based on hybrid multi-bit multiplicative rules controlled by secret keys. Two hybrid multiplicative multiwatermarking decoders, i.e., optimum and locally optimum, are proposed, which are based on the minimum Bayesian risk criterion and the DWT coefficients are modeled as the generalized Gaussian distribution. The BER (average bit error rate) as the evaluation index of the performance of optimum hybrid decoders is exactly analyzed. Finally, experimental results are shown to confirm the validity of the theoretical and empirical analysis.