Fixed Wireless Internet Access

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• Wired broadband internet access is not always available, especially in rural areas or older building developments, where running new cable capable of supporting DSL or full fiber is problematic
  • some sort of fixed wireless internet access might be an option

Geostationary Orbital Satellite Internet Access

• A satellite-based microwave radio system provides far bigger areas of coverage than can be achieved using other technologies
• transfer rates available vary between providers and access packages
  • 2 or 6 Mbps up and 30 Mbps down would be typical
• One drawback of satellites placed in a high geostationary orbit is increased latency
  • signal must travel over thousands of miles more than terrestrial connections
    • introducing a delay of many times what might be expected over a land link
    • is an issue for real-time applications, such as video conferencing, VoIP, and multiplayer gaming
    • E.g., if accessing an internet web server over DSL involves a 10–20 ms round trip time (RTT) delay on the link, accessing the same site over a satellite link could involve a 600–800 ms RTT delay
• To create a satellite internet connection:
  • the ISP installs a very small aperture terminal (VSAT) satellite dish antenna at the customer’s premises and aligns it with the orbital satellite
  • satellites are in high geostationary orbit above the equator, so in the northern hemisphere, the dish will be pointing south
  • Because the satellite does not move relative to the dish, there should be no need for any realignment
  • antenna is connected via coaxial cabling to a Digital Video Broadcast Satellite (DVB-S) modem

Low Earth Orbit Satellite Internet Access

• different type of service that uses an array of satellites positioned in low Earth orbit (LEO)
• support better bandwidth (around 70–100 Mbps at the time of writing)
• are lower latency (100–200 ms RTT)
• drawback is that the satellites move relative to the surface of the Earth
• customer’s premises antenna must be provisioned with a motor so that it can periodically realign with the array
• dish construction uses a technology called phased array to connect to different satellites as they pass overhead and minimize the amount of mechanical realignment required
• antenna must have a clear view of the whole sky

Wireless Internet Service Providers

A wireless internet service provider (WISP) uses ground-based long-range fixed access wireless technology.

• WISP installs and maintains a directional antenna to work as a bridge between the customer’s network and the service provider
• might use Wi-Fi type networking or proprietary equipment and licensed or unlicensed frequency bands

Drawbacks of fixed access wireless

• fixed access wireless link is often low latency, or at least, lower latency than satellite
• the actual unobstructed line of sight between the two antennas can be difficult to maintain
• if the provider uses unlicensed frequencies, there are risks of interference from other wireless networks and devices

Info

All types of microwave radio link can be adversely affected by snow, rain, and high winds.