SAFETY ENGINEERING EXPERIENCE ON MANNED MODULES AND INTERNAL / EXTERNAL PAYLOADS OF SPACE STATION

  • Ferrante M
  • Pesce C
  • Pochettino P

The Space Station program represents one of the most significant challenge from the safety point of view because it will be the first time that a considerable number of habitable modules, developed by different nations, will be permanently on orbit. Alcatel Alenia Space through ASI and ESA developed and has ...

FRAMEWORK FOR OPERATION AND MAINTENANCE (OAM) IN OPTICAL BURST SWITCHED NETWORKS

  • Cankaya H.
  • Chareranoon S
  • El Bawab T
  • Shin J.

The problem of operation and maintenance (OAM) in optical burst switched (OBS) networks is not addressed by the optical-networking community even though OBS has been gaining research interest in recent years. In this paper, we introduce a functional model of OBS networks and an OAM architecture that is designed to ...

DARWIN PRECURSOR DEMONSTRATION MISSION : THE ICC2 STUDY, FROM GNC DESIGN TO REAL-TIME TEST BENCH VALIDATION

  • Charbonnel C.
  • Pirson L

The implementation of a formation flying concept is being considered by ESA for the Darwin space interferometer mission, scheduled for 2015. In order to prepare this mission, some studies are led to demonstrate the feasibility of the global project. One of the critical points is the metrology chain and the ...

BALL BONDING PROCESS ROBUSTIFICATION WITH REGARD TO SPACE APPLICATIONS

  • Goffin B
  • Libon S
  • Paelinck P

Space applications require being able to pass 100% pull test, before and after thermal aging, and to conform to visual inspection. Gold thermosonic wirebonding (ball bonding) on aluminum metallized silicon dies is usually felt to be a sensitive process, due to the need for effectively controlling intermetallic. As the criteria ...

KEY CONTROL TECHNIQUES FOR GNC DESIGN OF MARTIAN VEHICLES

  • Le Peuvedic C
  • Maini M

The determination of the best control technique for a given application is not an easy problem, most of the time, the designer selects a technique depending on his/her own experience and with a preference for simplest ones. However, if such an approach is possible for most missions, it becomes insufficient ...

COROT : AN AOCS POWERED BY MISSION TELESCOPE

  • Brethe D
  • Rigaud O

PROTEUS development was initiated by CNES and ALCATEL at the end of 1996. The goal was to design and qualify a versatile small satellite bus, as well as a generic ground segment, able to accommodate various payloads for scientific or application missions. As it is an astronomical mission, COROT must ...

IN-FLIGHT GEOSTATIONNARY AOCS BASED ON STAR TRACKER

  • Brouillard E
  • Gaudic L
  • Pasquet J.
  • Renault H

As a conclusion, new AOCS performances are fully compliant to the system requirements and the expected behavior. Compared to the previous generation, AOCS design allows for transfer an on station operation simplification SODERN SED16/26 STR itself has shown a good behavior. Moreover, the tracking robustness has been tested in Van ...

SUGGESTED SOLUTIONS FOR THE NEAR-FAR EFFECT IN MULTIMODE WLANS

  • Brignol L
  • Brouet J.
  • Coupechoux M.
  • Kumar V.

A recent paper [1] has highlighted the near-far effect in IEEE 802.11b [2-3]. It has been observed that when some mobile node use a lower bit rate than the others, the performance of all nodes is considerably degraded. For example, a node transmitting at 1 Mbps reduces the throughput of ...

CROMA - A NEW MEDIUM ACCESS PROTOCOL FOR MOBILE AD HOC NETWORKS

  • Coupechoux M.
  • Kumar V.

A new medium access protocol for mobile ad hoc networks, called CROMA is proposed. CROMA is collision-free and receiver-oriented. It operates in a slotted environment in a dynamic and distributed way. In this protocol, receivers act as local base-stations and can manage one or several communications on a single slot. ...

ON THE CAPACITY OF THE CHANNEL AWARE SLOTTED ALOHA OVER RAYLEIGH AND NAKAGAMI-M CHANNELS

  • Coupechoux M.
  • Lestable T.

We consider the channel aware slotted ALOHA protocol that has been recently proposed to improve the capacity of the traditional slotted ALOHA by using multi-user diversity. This type of diversity is commonly used in scheduling policies that allow terminals to transmit when their channel conditions are good. Here, we focus ...

MODELING OF A SLOTTED MAC PROTOCOL FOR MANETS

  • Coupechoux M.
  • Kumar V.

Global positioning systems like GPS or GALLILEO will soon provide a very good timing accuracy, making possible the synchronization of nodes in a mobile ad hoc network (MANET). With this assumption, TDMA based MAC protocols can provide a very good utilization of the shared radio resources. This paper presents an ...

A SCHEDULING POLICY FOR DENSE AND HIGHLY MOBILE AD HOC NETWORKS

  • Coupechoux M.
  • Kumar V.

Recent publications in information theory demonstrated that mobility can increase the capacity of wireless ad hoc networks. More precisely, the throughput per source-destination pair can be kept constant as the density of nodes increases. Indeed, such enhancements are achievable as the node mobility provides a sort of multi-user diversity. Considering ...

USING LINUX FOR REAL-TIME APPLICATIONS

  • Ebert C.

We've selected a topic for practitioners in the embedded and real-time domains, namely how to use Linux for real-time applications. The article is hands-on: it not only summarizes selection criteria and introduction schemes for RTLinux but also shows how Linux was actually integrated in an existing (legacy) architecture. For small ...

CONTROL PLANE DESIGN FOR MULTI-LAYER RESILIENCE

  • Grammel G

With the concept of multi region networks resiliency across switching layers can be implemented in a standardized way. Multi-layer resiliency based on a MRN control plane allows to simplify provisioning and recovery on integrated networks across different transport layers. By exploiting these mechanisms an efficient resilience mechanism in multi layer ...

HYBRID SYNTHETIZERS IN SPACE : GALILEO'S CMCU

  • Alonso L.
  • Carrillo F.
  • Sanchez A A.

Galileo satellite navigation system employs as master navigation signal a 10.23 MHz tone generated from several 10MHz atomic clock references. The Clock Monitoring and Control Unit (CMCU) synthesizes dais navigation signal from one of the four embarked atomic clocks. The CMCU has to comply with very stringent requirements in order ...

AN EMBEDDED SOLUTION TO IBGP OSCILLATIONS

  • Lafragette J.
  • Levy T.
  • Marce O.

The occurrence of oscillations in the border gateway protocol (BGP [Rekhter, Y et al., 1995]) has been discussed in many papers. Autonomous system (AS) configurations using route reflection [Bates, T et al., 2000] are considered to be especially sensitive to oscillations ([Mc Pherson et al., 2002], [Griffin, T et al., ...

FABRICATION AND CHARACTERIZATION OF LOW LOSS PHOTONIC CRYSTAL WAVEGUIDES BASED ON INP SUBSTRATE

  • Cuisin C.
  • Derouin E.
  • Drisse O.
  • Duan G.
  • Le Gouezigou L.
  • Le Gouezigou O.
  • Pommereau F.

Photonic crystal waveguides, fabricated on InP substrate using an inductively coupled plasma etching process, show propagation losses of 40dB/mm with one missing row and of less than 10 dB/mm with three missing rows.

EXPERIMENTAL STUDY OF THE IMPACT OF OPTICAL CONFINEMENT ON SATURATION EFFECTS IN SOA

  • Brenot R.
  • Duan G.
  • Landreau J.
  • Le Gouezigou L.
  • Le Gouezigou O.
  • Lelarge F.
  • Martin F.
  • Pommereau F.
  • Rousseau B.

Measurements of SOA with various optical confinements show that low confinement devices are not saturated by ASE. This allows them to have good inversion factors at their input section, which leads to state-of-the-art noise factors.

LOW-LATENCY SECURE MOBILE COMMUNICATIONS

  • Choyi V.

On the one hand, the challenge of meeting various security requirements in the mobile and wireless environment is difficult, compared to the fixed and wired environment, because of the very nature of radio communications. On the other hand, wireless networks such as GSM, PCS and CDMA, which are predominantly circuit-switched ...

EAM DFF-DRIVER OPTIMIZATION FOR 40 GB/S TRANSMITTER

  • Blache F.
  • Godin J.
  • Jorge F.
  • Kazmierski C.
  • Konczykowska A.

In this paper we present the design and measurements of an integrated EAM DFF-driver IC devoted to EAM-based ETDM transmitter. Different design aspects like architecture choice, power consumption, and layout optimization are addressed to solve specific design constraints. This IC was fabricated in an InP DHBT technology. A high quality ...