Towards generic satellite payloads: software radio

Satellite payloads are becoming much more complex with the evolution towards multimedia applications. Moreover satellite lifetime increases while standard and services evolve faster, necessitating a hardware platform that can evolves for not developing new systems on each change. The same problem occurs in terrestrial systems like mobile networks and a foreseen solution is the software defined radio technology. In this paper we describe a way of introducing this concept at satellite level to offer to operators the required flexibility in the system. The digital functions enabling this technology, the hardware components implementing the functions and the reconfiguration processes are detailed. We show that elements of the software radio for satellites exist and that this concept is feasible

Reliability-aware multi-segmented bus architecture for photonic networks-on-chip

Network-on-chip (NoC) has emerged as an enabling platform for connecting hundreds of cores on a single chip, allowing for a structured, scalable system when compared to traditional on-chip buses. However, the multi-hop wireline paths in traditional NoCs result in high latency and energy dissipation causing an overall degradation in performance, especially for increasing system size. To alleviate this problem a few radically different interconnect technologies are envisioned. One such method of interconnecting different cores in NoCs is photonic interconnects. Photonic NoCs are on-chip communications networks in which information is transmitted in the form of optical signals. Photonic interconnection is one of the leading examples of emerging technology for on-chip interconnects. Existing innovative photonic NoC architectures have improved performance and reduced energy dissipation. Most architectures use Wavelength Division Multiplexing (WDM) on the photonic waveguides to increase the data bandwidth. However they have issues relating to reliability, such as waveguide losses and adjacent channel crosstalk. These phenomena could have a crippling effect on a system, and most current architectures do not address these effects. A newly proposed topology, known as the Multiple-Segmented Bus topology, or MSB, has shown promise for solving, or at least reducing, many of the problems plaguing the design of photonic networks using a modification of a folded torus to transmit different wavelength signals simultaneously. The MSB segments the waveguides into smaller parts to limit the waveguide losses. The formal performance evaluation of this proposed architecture has not been completed. This thesis will analyze the performance of such a network when implemented as a NoC in terms of data bandwidth, energy dissipation, latency, and reliability. By analyzing and comparing performance, energy dissipations, and reliability, the MSB-based photonic NoC (MSB-PNoC) can be compared to other state-of-the-art photonic NoCs to determine the feasibility of this topology for future network-on-chip designs

A critical analysis of research potential, challenges and future directives in industrial wireless sensor networks

In recent years, Industrial Wireless Sensor Networks (IWSNs) have emerged as an important research theme with applications spanning a wide range of industries including automation, monitoring, process control, feedback systems and automotive. Wide scope of IWSNs applications ranging from small production units, large oil and gas industries to nuclear fission control, enables a fast-paced research in this field. Though IWSNs offer advantages of low cost, flexibility, scalability, self-healing, easy deployment and reformation, yet they pose certain limitations on available potential and introduce challenges on multiple fronts due to their susceptibility to highly complex and uncertain industrial environments. In this paper a detailed discussion on design objectives, challenges and solutions, for IWSNs, are presented. A careful evaluation of industrial systems, deadlines and possible hazards in industrial atmosphere are discussed. The paper also presents a thorough review of the existing standards and industrial protocols and gives a critical evaluation of potential of these standards and protocols along with a detailed discussion on available hardware platforms, specific industrial energy harvesting techniques and their capabilities. The paper lists main service providers for IWSNs solutions and gives insight of future trends and research gaps in the field of IWSNs

Human brain distinctiveness based on EEG spectral coherence connectivity

The use of EEG biometrics, for the purpose of automatic people recognition, has received increasing attention in the recent years. Most of current analysis rely on the extraction of features characterizing the activity of single brain regions, like power-spectrum estimates, thus neglecting possible temporal dependencies between the generated EEG signals. However, important physiological information can be extracted from the way different brain regions are functionally coupled. In this study, we propose a novel approach that fuses spectral coherencebased connectivity between different brain regions as a possibly viable biometric feature. The proposed approach is tested on a large dataset of subjects (N=108) during eyes-closed (EC) and eyes-open (EO) resting state conditions. The obtained recognition performances show that using brain connectivity leads to higher distinctiveness with respect to power-spectrum measurements, in both the experimental conditions. Notably, a 100% recognition accuracy is obtained in EC and EO when integrating functional connectivity between regions in the frontal lobe, while a lower 97.41% is obtained in EC (96.26% in EO) when fusing power spectrum information from centro-parietal regions. Taken together, these results suggest that functional connectivity patterns represent effective features for improving EEG-based biometric systems.Comment: Key words: EEG, Resting state, Biometrics, Spectral coherence, Match score fusio