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Giovanni Garofalo European Space Agency PowerPoint Presentation
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Giovanni Garofalo European Space Agency

Giovanni Garofalo European Space Agency

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Giovanni Garofalo European Space Agency

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  1. DVB RCS Standards & Future Evolutions Giovanni Garofalo European Space Agency

  2. DVB-RCS Background • DVB-RCS defines a return channel over satellite for broadband systems based on DVB-S(2) forward link • Specification initially defined by satellite operators working under the auspices of ESA • Work taken over by DVB Project, which is responsible for standard maintenance • ETSI approves its publication as EN 301 790, according to their defined procedures • Definition started in Sept 1997 • Editions • 1st (v1.2.2)12/00 • 2nd (v1.3.1) 03/03: RSAT • 3rd (v1.4.1) 09/05: DVB-S2

  3. Open Standards Principles • OpennessAll stakeholders participate in the standards development process • ConsensusAll interests are discussed and agreement found • Due ProcessBalloting and appeal process may be used to find resolution • Open IPRHolders of Intellectual Property Rights (IPR) must identify themselves during the standards development process • Open WorldSame standard for the same function world-wide • Open AccessOpen access committee: documents, drafts and completed standards • Open MeetingAll may participate in standard development meetings • On-going SupportStandards supported until user interest ceases rather than when provider interest declines • Open InterfacesAllow additional functions, public or proprietary • Open UseLow or no charge for IPR necessary to implement an accredited standard

  4. The case of DVB-RCS: • Open standard • Scrutinised, optimised, built by consensus • Based on commercial requirements • Broad range of services and applications supported • Future-proof (e.g. DVB-S2) • Based on successful DVB-S • Availability of mass market low cost satellite TV receivers Enables interoperability between products

  5. The case of DVB-RCS: • Multiple implementations • Several system integrators • Several terminal-only suppliers • Different choices of options and parameters • Several generations of system implementations • Cost & feature optimised Enables interoperability between products

  6. SatLabs Group basics • Association set up to bring the DVB-RCS standard to large-scale adoption • Foster availability of interoperable products • Ensure availability of solutions for interoperability testing and certification • Membership open to all organizations worldwide interested in the DVB-RCS standard • Main emphasis on interoperability but addressing other aspects related to DVB-RCS implementation • Creation: October 2001

  7. Avanti Aramiska FranceTelecom MonacoTelecom Satlynx Alcatel Astrium Eutelsat HellasSat Hispasat JSAT NewSkies SESAstra Telesat Alcatel EMS Gilat HNS Nera Newtec Pentamedia Shiron ViaSat Alcatel Bell NDSatcom Thomson AASKI Invacom Skyware Spacebridge STMicro Verisat Visiosat SatLabs Membership Service + Access Provider Satellite Operator Satellite Supplier System Supplier Equipment Supplier Techno Supplier

  8. DVB-RCS Standards Overview

  9. DVB-RCS Reference Diagram Network ControlCentre: a NCC provides Control and Monitoring Functions (CMF). It generates control and timing signals for the operation of the Satellite Interactive Network to be transmitted by one or several Feeder Stations. Traffic Gateway: a TG receives the RCST return signals, provides accounting functions, interactive services and/or connections to external public, proprietary and private service providers (data bases, pay-per-view TV or video sources, software download, tele-shopping, tele-banking, financial services, stock market access, interactive games etc.) and networks (Internet, ISDN, PSTN, etc.). Feeder: a Feeder transmits the forward link signal, which is a standard satellite digital video broadcast (DVB-S or DVB-S2) uplink, onto which are multiplexed the user data and/or the control and timing signals needed for the operation of the Satellite Interactive Network.

  10. Continuous Rate Assignment MAC Characteristics Volume Based Dynamic Capacity Rate Based Dynamic Capacity

  11. Burst characteristics

  12. Overhead Bursts

  13. MF-TDMA (Multi Frequency TDMA) terminal 1 terminal 2 frame terminal 3

  14. Terminal architecture Interfacility Link: RX cable: FL signal on L-Band (950 – 2150 MHz)+ polarization control +DC power (~10-20 volts) + to LNB (Low Noise Block) + 22 KHz tone (LNB frequency band adjustment) • TX cable: RT link L-Band TX (950-1450 MHz)+10 MHz reference signal to ODU (BUC) + DC power to the BUC (20-30 volts) + 22 KHz PWK (Pulse Width Keying) DiSEqC tone DiSEqC (Digital Satellite Equipment Control): SSPA ON/OFF, TX frequency band selection, …, ODU monitoring (SSPA status, PLL status, …)

  15. Hub Architecture (1) • FLSS (Forward Link Subsystem) • IP/DVB encapsulator • Injects IP packets into MPEG2/DVB compliant Transport Stream • •MPEG2-DVB Multiplexer: • Combines the MPEG Transport Streams from the IP/Encapsulator and the RLSS Controller/Scheduler • PCR Inserter • Generates a 27 MHz reference clock and inserts relative time stamps in the FW link for network synchronization. • DVB Modulator • Modulates the signal to IF frequency (L-band) according to the DVB-S or DVB-S2 standard

  16. Hub Architecture (2) • RLSS (Return Link Subsystem) • MCD (Multiple Carrier Demodulator): • Demodulation of return path carriers, De-Multiplexing of traffic and Signaling • Timing/frequency corrections • •Receiver Traffic: • ATM recovery from Satellite cells. • Interface with ISP through ATM Switch • •Receiver Signaling: • Forward received signaling to Controller/scheduler. • •Control/Scheduler • Controls SITs entry and generates all Satellite signaling on the forward path • •OAM (Operation, Administration and Maintenance) • Responsible for initializing, configuring and monitoring all RLSS functions to ensure proper operation

  17. Hub Architecture (3): IPSS

  18. DVB-S Multiple streams: No Input bit rate: fixed Coding: Reed Solomon plus convolutional encoding Coding rates: ½, 2/3, ¾, 7/8 Input I/F: MPEG TS Symbols mapping: Gray Modulation format: QPSK Pilot symbols: None Symbols shaping: Square-Root Raised Cosine filter =0.35 Transmission mode: constant Coding and Modulation DVB-S2 Multiple streams: Yes Input bit rate: variable frame-by-frame Coding: BCH + Low-Density Parity Check Codes (LDPC) Coding rates: ¼, 1/3, 2/5, ½, 3/5, 2/3, ¾, 4/5, 5/6, 8/9, 9/10 Symbols mapping: BICM (Gray) Modulation format: QPSK, 8PSK, 16APSK, 32APSK Pilot symbols: Optional Symbols shaping: Square-Root Raised Cosine filter =0.2, 0.25, 0.35 Input I/F: MPEG-TS, IP Transmission modes: Constant Coding and Modulation, Variable Coding and Modulation, Adaptive Coding and Modulation DVB-S versus DVB-S2

  19. DVB-S2/DVB-S Summary • bit-rate gain (same C/N and symbol-rate): 25-35% depending on modes and applications • Large flexibility to potentially match any transponder characteristics: • Spectrum efficiencies from 0.5 to 4.5 bit/s/Hz • C/N range from –2.4 to +16 dB with 1 dB granularity (AWGN) 0.7 – 1 dB from the Shannon limit probably means that: “In the course of our lifetime we will never have to design another system for satellite broadcasting”

  20. AlternativeVSATAccess Systems

  21. IPoS: IP over satellite • Originally published as TIA-1008, now also co-published by ETSI • Promoted by HNS • Always-on IP service: once registered the terminal does not need to ever log-on again • Protocol architecture separate satellite-dependent functions and satellite independent functions via the SI-SAP interface positioned between the MAC and Network Layer. Elements above the SI-SAP can be designed without knowledge of the supporting satellite link layer • Return link access similar to DVB-RCS but with O-QPSK and variable length bursts • Support of contention-based access

  22. DOCSIS-S • Originally developed as terrestrial cable modem standard • Promoted by ViaSat • Consists of terminals (CM; Cable Modems) and Hub’s (CMTS: Cable Modem Termination System) • DOCSIS-S implements DOCSIS 1.1 above the PHY Layer and a satellite specific PHY Layer • Potential to save some costs on reuse of higher layer components • Benefits from the availability of a very mature sets of infrastructure products for network control, system management, subscriber management and billing systems • FW link PHY based on turbo code with ACM (QPSK and 8PSK) • MAC layer contains a 6 byte MAC header and a ETHERNET packet as a payload. Encapsulation of IP packets requires an additional 17 Bytes header and a CRC32

  23. VIASAT SurfBeam System • Telesat is using SurfBeam for consumer services in Canada on new Anik F2 Ka-band, spot beam satellite

  24. SurfBeam: ACM

  25. Satcom Systems: comparison

  26. DOCSIS vs. DVB-RCS

  27. Future DVB-RCS Standards Improvement Axis

  28. Future Systems Based on WEB (West Early Bird) system design

  29. Improved Coding Scheme 8PSK QPSK • Optimum bits-> symbol mapping strategy • Several rates available Performance is improved by as much as 1.2 dB! Preliminary Results

  30. Received power Nominal power target Transmitted power Fading Mitigation Techniques Efficient FMT’s require the implementation of high order modulations (8PSK and 16APSK)Adaptive Coding and Modulation already successfully implemented in the DVB-S2 FW link FMT: ACM (Adaptive Coding and Modulation ACM in the RT link 60% capacity increase! FMT: DRA (Dynamic Rate Adaptation) FMT: UPC (Upstream Power Control) UPC case

  31. Improvement Axis (2) • Efficient Framing/Encapsulation: utilization of few burst lengths, which are multiples of a basic slot size 20% Efficiency gain • Continuous Phase Modulations for Return Channel: Reduced complexity for receiver! • Random Access together with DAMA: Adapts very well to bursty type of traffic and to consumer user profile

  32. ESA Strategy for DVB-RCS

  33. ESA has played a key role in the definition of the DVB-RCS standard since its initial stages. ESA actively supports the development of DVB-RCS in the following areas: DVB-RCS standardization Technology R&D System R&D Application development Pilot projects ESA and DVB-RCS: Background

  34. SatLabs Group ESA fostered the creation of the SatLabs Group and is leading its tasks • Ensure interoperability between DVB-RCS terminals and systems • Achieve low-cost implementations of DVB-RCS products • ESA is chairing the SatLabs Group • ESA leads most working groups and actively participates in the technical tasks directly or through funded studies • Key developments for the implementation of interoperability verification are carried out by ESA • Common Test Bed for interoperability testing • ESA funds through ARTES lineskey technological developments needed to reduce DVB-RCS cost • Low cost Components • Low cost installation mechanisms

  35. Applications Applications are the bridge between the End User and the DVB-RCS technology ESA has developed and integrated DVB-RCS HW/SW elements and contents under ARTES program in order to generate new applications with commercial potential, and addressing the capability to provide the applications in an Operational Context • Supporting provision of Broadband Access Services through PILOT projects: All activities involve a user community through a pre-operational phase of actual utilisation of the system (e.g. Broadband in the Sky, Pacific Skies, Inspire, SpaceforScience) • Developing “Applications” suitable for DVB-RCS broadband access services • Telemedicine • Teleducation • Secure access • E-government • Infomobility • B2B

  36. Budget evolution DVB-RCS R&D