Satellite Communications - State of Art

Modern satellite communications networks and systems rely on innovations in both the radio frequency (RF) and baseband domains. Introduction and application of these cutting-edge technologies and processes are addressed by this in-depth three-day course. Established during the last decade, technologies that make a difference include high throughput satellites, high power solid state amplifiers (up to one kW), array antennas for mobile platforms, channel linearization, turbo codes, DVB-S2 extensions and adaptive coding and modulation (ACM). The path forward involves the right choices in terms of which technologies and their introduction – and the use of integrating tools such as system simulation and optimization. Investments in new satellites, earth stations and network management systems need the right system-level view, and at the same time, demand a thorough understanding of the underlying details within the RF aspects (propagation, link availability and throughput) as well as the ability of baseband systems to provide throughput under expected conditions and to end users. The course examines real options and makes use of quantitative analysis methods and systems analysis to evaluate the technology horizon.

• Current and projected satellite designs, payloads and capabilities
• Structure of ground segments, earth stations and user terminals looking forward
• Terminals and networks for high speed communications on the move (COTM)
• Innovative systems engineering concepts and solutions – simulation using STK and other tools
• Evolving standards used in the baseband and network – DVB-Sx (extensions), ACM in its next generation, Internet Protocol acceleration
• The future built around solid state amplifiers – GaN technology, linearization, single and multi carrier operations under highly dynamic conditions
• Innovations in multiple access systems – MF-TDMA, CDMA, carrier cancellation, 2D-16 State Trellis Coded Modulation (TCM)
• Control of radio frequency interference (RFI) – overcoming challenges in mobile and broadband applications
• Planning steps for upgrading or replacing current with state-of-the-art technology
• How technology will evolve in coming years, reflecting changes in technology and user requirements

• Orbit and spectrum resources available in North America and globally
  Geostationary
  Non-geostationary
• Satellite operators and their orbital resources
  Intelsat (C, Ku)
  SES (Ku)
  Inmarsat (L, Ka)
  Telesat (C, Ku, Ka)
  Eutelsat (Ku)
  Regional operators (JSAT, Thaicom, AsiaSat, ABS, RSCC, Arabsat, Thuraya, YahSat)
  US government (narrowband, wideband, protected)
• The ground segment – operators and capabilities
  Major service operators (DIRECTV, Iridium, ViaSat, Hughes)
  Teleport operators (GlobeCast, Harris CapRock, Encompass, EMC)
  User networks (consumer, commercial, aeronautical, homeland security, military) Advanced Spacecraft and Communications Payload Design
• Satellite footprint coverage and antenna structures
  Relative merits of area coverage versus spot beams
  Overall architecture for high throughput for broadband services
  Broadcast systems for HD and other digital content
• Low noise front ends
• Switching and processing
• High power amplification and linearization
• Spacecraft support – power, thermal and structural
• Large versus small satellites – trades on cost and risk Earth station design innovation
• Antenna systems
  Fixed antenna systems – Ka band, circular polarization
  Mobile antennas – Comm on the Move, aeronautical
  Portable antennas – compact, rapid deployment and auto-pointing
  Array antennas – feasibility and cost
• RF amplification
  Low noise amplification – optimizing G/T
  GaN technology – capability and benefits
  Amplifier types – Class AB, F, G, Dougherty
  SSPA architecture – power combining, fault tolerance, hot swapping
  Low-loss output combining and power transfer to the antenna
  Reducing prime power requirements
• Multiple access and dynamic bandwidth management
  VSAT systems employing MF-TDMA, CDMA and FDMA
  Dynamic capabilities to be exploited - Adaptive Coding and Modulation with SVB-S2
  Areas open to innovation – access control, DAMA and QoS
• Monitor and control
  Basic capabilities for device M&C
  M&C systems – local and remote control
  Spectrum monitoring using remote access Baseband systems – MODCOD and Adaptive Coding and Modulation (ACM)
• Review of DVB-S2 and turbo codes
• Extensions to DVB-S2 (DVB-Sx)
  General benefits – more MODCOD options (including 64APSK), less roll-off (greater spectral efficiency)
  Novelsat
  DVB Forum – Newtec et al
• The next wave of ACM – enhanced VSAT networks (two way services), 2D 16 State TCM
• Integration with IP and the terrestrial network
  Updating the Performance Enhancing Proxy (PEP) for acceleration
  Application enhancements
  Accommodating the VPN Transponder loading and optimization
• Characterization of the bent pipe transponder
  Frequency response and bandwidth
  Amplifier linearity – TWTA and SSPA – intermodulation distortion (IMD) characteristics
  Frequency plans and their impact on capacity
• Traffic bearing capability of multi-beam systems
  Topology of the multi-beam network – 3, 4 and 7 color reuse patters
  C/I considerations and impact on the link budget
  Traffic distribution optimization Radio Frequency Interference (RFI) identification, mitigation and control
• Classification of interference – harmful, unacceptable, acceptable
• RFI location using interferometry
• Carrier ID – on the carrier, under the carrier
• RFI investigation process
  Type of interference
  Likely sources – internal, local, same satellite, adjacent satellite, unknown
  Reducing the interference – avoidance, filtering, cancellation
• Role of good operating practices
  Transponder access control
  Monitoring and testing Digital transmission characteristics, impairments, and their mitigation
• Update on propagation – Ka band impacts from rain and clouds
• Transponder characterization
  AM/PM
  Group delay
  Spurious
  Frequency error, phase noise
• Operating modes
  Backoff
  Linearization on satellite and on the ground
• Test and simulation tools
  Transfer characteristics (amplitude and phase, converting to C/IM)
  Noise Power Ratio (NPR) testing
  Microwave link analysis
  Visualization tools - STK
  Simulation - Simulink Evolving technology and design practices
• The business of the satellite operator – how to make better deals
• Trends in COTM as related to aeronautical and maritime
• Technology development and introduction – on the ground and in space
• How to anticipate changes in requirements and technology
• Planning for the future – discussion

Bruce R. Elbert, MS (EE), MBA, Adjunct Professor (ret), College of Engineering, University of Wisconsin, Madison. Mr. Elbert is a recognized satellite communications expert and has been involved in the satellite and telecommunications industries for over 40 years. He founded Application Technology Strategy, LLC, to assist major private and public sector organizations that develop and operate cutting-edge networks using satellite and other wireless technologies During 25 years with Hughes Electronics, he directed the design of several major satellite projects, including Palapa A, Indonesia’s original satellite system; the Galaxy follow-on; and the development of the first GEO mobile satellite system capable of serving handheld user terminals. Mr. Elbert was also ground segment manager for the Hughes system, which included eight teleports and 3 VSAT hubs. He served in the US Army Signal Corps as a radio communications officer and instructor. By considering the technical, business, and operational aspects of satellite systems, Mr. Elbert has contributed to the operational and economic success of leading organizations in the field. He has written nine books on telecommunications and IT.