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© 2008 VT iDirect, Inc.
Mesh TechnologyTony Naaman
Systems Architecture iDirect, USA
Evolutions in Satellite Telecommunication Ground Segments5 - 6 June 2008 - ESA/ESTEC - Noordwijk, The Netherlands
Agenda
• Introduction• Star & Mesh Networks• Mesh Scalability, Transmit & Receive Hopping
• Mesh• Markets & Applications• Technical Challenges• Market Trends• Enabling Technologies
• Internet Routing In Space (IRIS)• Overview• Routing, Scalability & QoS
© 2008 VT iDirect, Inc.
Introduction
Star Network
RF
Shared SCPC
Outbound
Star TDMA
Inbound
Hub
Remote-to-Remote Communication in Star Network
RF
Shared SCPC
Outbound
Star TDMA
Inbound
Hub
Remote-to-Remote Disadvantages in Star Network
• Latency • Critical for Real-Time Applications• Double Hop over the Satellite
• Inefficient use of Satellite Bandwidth• Remote-to-Remote Traffic requires Twice the Bandwidth of Star
Traffic
Remote-to-Remote Communication with Mesh Carrier
RF
Shared SCPC
Outbound
Star TDMA
Inbound
Hub
Mesh TDMA Carrier
Mesh Network – Scaling & Transmit Hopping
RF
Hub or Master Station
Mesh TDMA
Carriers
Mesh Network – Scaling & Receive Hopping
Large Stations
Mesh TDMA
Carriers
Small Stations
© 2008 VT iDirect, Inc.
Mesh Market, Technology & Trends
Mesh Markets & Applications
• Mesh Market Segments• Enterprise Networks
• Cellular Networks• Oil & Gas• Enterprise Connectivity• Distance Learning
• Government & Military• Embassy Networks• Disaster Management• Homeland Security• Defense
• Mesh Applications• VoIP• Video Conferencing• Cellular Backhaul (Move to Local Routing)• Other Data Applications
Mesh Technical Challenges
• Link Budget• Small Antenna & Limited Transmit Power
• Small Carriers => Need Multiple Carriers for Scaling
• Different Terminal Sizes & Rain Fade• Multi Symbol Rates, Modulation and Coding
• Timing & Frequency Tracking• Clock Inaccuracy & Doppler Shift
• Reference Source from Hub or Master Controller• Closed Loop for Adjustments
• Uplink Power Control• For all Carriers and Remote Terminals
• Closed Loop for Adjustments
• Transmit & Receive Hopping• Multi Symbol Rates, Modulation and Coding• Frequency Range - Across Transponders
• Single vs. Dual Transmitters• Multi-Demodulators vs. Receive Time Plan
Mesh Market Trends
• Higher Data Rates
• Larger Networks – Scalability
• More Flexibility – Hybrid Networks
• Improved Bandwidth Efficiency
• Lower Cost of Ownership
Enabling Technologies – Higher Data Rates
• Faster Processor on Remote Terminal• Larger FPGA & Memory• Remote Terminal Hardware Cost going Down
• Antenna, BUC, Processor, FPGA, Memory
• Faster Transmit & Receive Hopping• Multi-Demodulators for Simultaneous Receive of
Multiple Carriers• Hub or Master Controller
• Tighter Timing & Frequency Control• Better Bandwidth Management
Enabling Technologies – Scalability
• Transmit & Receive Hopping• Across Transponders• Multiple Symbol Rates, Modulation & Coding
• Intelligent Bandwidth Management Software• Transmit Time Plan• Receive Time Plan or Mesh Carrier Load Balancing
Enabling Technologies – Flexibility
• Hybrid Networks• Shared SCPC Outbound from Hub
• DVB-S2/ACM for Increased Efficiency
• TDMA Return to Hub (Star)• Remotes with Low or Irregular Traffic Pattern
• SCPC Return to Hub (Star)• Remotes with Steady Traffic Pattern
• TDMA Mesh between Remote Terminals• Remotes with Low or Irregular Traffic Pattern
• SCPC Mesh between Remote Terminals• Remotes with Steady Traffic Pattern
• Multiple Transmit• Example: SCPC to some Destinations & TDMA to Others
Enabling Technologies – Bandwidth Efficiency
• Adaptive FEC Rates• For Large Networks with Multiple Carriers
• Multiple Symbol Rates• Multiple Modulation (8PSK, QPSK, BPSK, Spread Spectrum)
• Real-Time Monitoring of SNR for each Remote Terminal & Optimal Carrier and FEC Chosen
• Intelligent Bandwidth Management System Generates Optimal Time Plan
Enabling Technologies – Low Cost of Ownership
• Sharing Hub & Space Segment Cost among Multiple Network Operators• Group QoS (GQoS) allows Sharing of Space Segment while
Logically Partitioning Bandwidth for Multiple Networks• Virtual Network Operator (VNO) allows Multiple Network
Operators to Manage their Networks Independently while Sharing Hub Equipment, Space Segment and Network Management System & Maintaining Total Privacy
• Lower Cost of Remote Terminal Hardware
Economically Viable Meshfor Small Enterprise Networks
© 2008 VT iDirect, Inc.
Internet Routing In Space (IRIS)
Internet Routing In Space (IRIS)
• Concept• On-Board Processing & Routing of IP Packets
• Routing across Transponders• On-Board Routing & Multicast Distribution
• Routing across Co-located Satellites• WiMax in Space
• Routing across Distant Satellites• Laser Inter-Satellite Link (ISL)
Scalable, Full-Mesh, Single-Hop Connectivity
Remote-to-Remote & Remote-to-Hub with IRIS
RF
Hub
Router
DVB-S2 Out
Hub In
Remote Terminals TDMA In
Hub-to-Remote Communication with IRIS
RF
Hub
Router
DVB-S2 Out
Hub In
Remote Terminals TDMA In
Accessing Google.com with Traditional Broadband
Accessing Google.com with IRIS
Transponder-1 Transponder-2
Router
Accessing Google.com with IRIS & Laser ISL
Router Router
Capacity Sizing with IRIS
• Remote Inbound Traffic
= Mesh + Star Inbound
• Internet Traffic Asymmetrical
(Star Out = n * Star In)
• S2 Capacity
= Mesh Traffic
+ Star In Traffic
+ Star Out Traffic
Hub In
S2
TDMA Inbound
Internet
Mesh Traffic
Star Out Traffic
Star Out Traffic
Star In Traffic
Mesh & Star In Traffic
Star In Traffic
• Hub In Traffic uses much better Modulation & Coding than TDMA Inbound
• S2 Outbound uses ACM
• Note: QoS becomes more complex with Routing across Transponders & Satellites
Routing, Scalability & QoS with IRIS
Hub In
XP1
Hub In
XP2
Hub In
XP3
S2 XP3
S2 XP2
S2 XP1
TDMA XP2
TDMA XP1
TDMA XP3
Router
Region-1 Region-2 Region-3
Region-1 Region-2 Region-3
Internet Routing In Space (IRIS) - Advantages
• Scalability• Across Transponders & Satellites
• Link Budget• Signal Reconstruction• Higher Data Rates with Smaller Antenna & BUC
• On-Board Packet Replication• Multicast Applications
• Still Require:• Bandwidth Management (Group QoS)• Adaptive Schemes for Bandwidth Efficiency• Complexity On-Board or Ground Segment – Trade Off
© 2008 VT iDirect, Inc.
Thank you