SATCOM 101 Webinar Notes

Jul 12, 2024

SATCOM 101 Webinar

Welcome and Introduction

  • Speaker: Diana, Marketing Communications Manager at North SAT
  • Purpose: Introduction to key principles of satellite communications
  • Main Presenter: Rodrigo Aguilar, Customer Service Engineer
    • 15+ years of experience in satellite communications
    • Bachelor of Science in Electronics and Communications Engineering

Rodrigo's Presentation

Overview

  • Fundamentals of satellite communications and SATCOM systems
  • Topics covered:
    1. Introduction to satellite communications
    2. Fundamental mechanics
    3. Frequencies and bands
    4. Earth stations and components
    5. Key considerations for selecting satellite terminals and components

Introduction to Satellite Communications

  • Definition: An object in space that circles around a larger object
  • Main Function: Retransmit received signal back to Earth
  • Applications:
    • Voice and telephone
    • Television and radio broadcast
    • Network and internet access
    • Navigation and GPS
    • Scientific research and meteorology
    • Military and commercial uses

Types of Satellite Orbits

  • Low Earth Orbit (LEO): Close to Earth, used for Hubble telescope and ISS
  • Medium Earth Orbit (MEO): Slower, 12 hours per revolution, used for GPS, GLONASS
  • Geostationary Orbit (GEO): Matches Earth's rotation, used for most communications satellites
  • High Earth Orbit (HEO): Farthest, used for scientific research

Advantages and Disadvantages of Satellite Communications

  • **Advantages: **
    • Cost is distance-independent
    • Reduced cost compared to long landlines in remote areas
    • Mobility and adaptability
  • Disadvantages:
    • High cost of specialized equipment
    • Limited frequency spectrum
    • Susceptible to electromagnetic interference and environmental conditions

How Satellite Communications Work

  • Earth Stations: Source and recipient, transmit and receive signals
  • One-Way Communication: Broadcast (e.g., satellite TV)
  • Two-Way Communication: Point-to-point (e.g., internet data)

Components of an Earth Station

  • Uplink: Signal sent to satellite
  • Downlink: Signal received by earth station
  • Amplification: Needed to compensate for signal loss
  • Antennas: Parabolic geometry, used for high-directional beams
  • Types of Antennas: Front feed and offset feed

Communication Subsystem of a Satellite

  • Transponders: Receive, amplify, filter, and rebroadcast signals
  • Polarization: Linear and circular, allows frequency reuse
  • Frequency Bands:
    • C band (4-8 GHz): Used for voice/data, larger antennas, better under adverse weather
    • X band (8-12 GHz): Used for military and mobile applications
    • Ku band (10-18 GHz): Used for consumer access, smaller antennas, affected by weather
    • Ka band (26-40 GHz): Used for broadband, smaller antennas, vulnerable to weather

Earth Station Components

  • Types: Fixed, portable, and on-the-move (e.g., vehicles, maritime, airborne)
  • Key Components:
    • Modulators, demodulators, and modems
    • Amplifiers (BUCs, LNBs)
    • Filters and reflectors
    • Outdoor units (ODU) and Indoor units (IDU)
    • Inter-facility link (IFL)

Link Budget

  • **Summary of power gains/losses in a communication system
  • Ensures adequate signal level for proper information recovery
  • Factors: Amplification, atmospheric propagation, antenna size

Key Considerations for Selecting SATCOM Equipment

  • Frequency Band: Consider regional regulations
  • Application Type: Fixed or mobile
  • Special Requirements: Output power, reflector size, auto-pointing mechanisms
  • Portability: Size and weight considerations
  • Environmental Conditions: Weatherproofing and durability

Questions and Answers

  • **Common Questions: **
    • OMT (Ortho Mode Transducer): Splits linear polarization (horizontal/vertical)
    • LNB Lifespan: Depends on environmental conditions and manufacturer's specs
    • Reflector Shape: Usually circular, affects electromagnetic wave reflection
    • Modem Protocols: Multiple standards (e.g., DVB), optimized for different applications
    • 5G Interference: Filters to reduce interference in c-band
    • Transition from Ku to Ka: Reflector size, BUC, and LNB modifications
    • Difference between SSPA and TWTA: Amplifier types, technology used

Conclusion

  • Thank You: For attending
  • Recording Available: Will be sent out, along with a survey for feedback
  • Contact Information: For further queries or assistance