Satellitebased

Satellite-based refers to systems and services that rely on artificial satellites in space to perform functions such as communications, navigation, Earth observation, or timing. It encompasses technologies deployed in various orbits and used across multiple industries, from consumer broadband to scientific research.

The major domains include satellite-based communication (satcom), delivering broadband or broadcast services via geostationary, medium, or low Earth orbit satellites; satellite-based navigation (GNSS) providing precise timing and position signals; and satellite-based Earth observation and remote sensing supplying imagery and data for weather, agriculture, geology, and security. Notable examples are Starlink and OneWeb for internet access, GPS/GLONASS/Galileo for positioning, and Landsat or Copernicus Sentinel missions for imagery.

Technical aspects encompass different orbital regimes, with GEO offering wide-area coverage and higher latency, while LEO and MEO provide lower latency and higher revisit rates. Satellite systems use various frequency bands, such as L-band for navigation and C/Ku/Ka bands for communications. The signal path involves uplink from ground stations to the satellite and downlink to users, supported by a ground segment of control centers and user terminals. In navigation, receivers determine position by processing signals from multiple satellites.

Applications and benefits include global communications, remote sensing, navigation for transport, disaster response, scientific research, and precise timing for networks and financial systems. Satellite-based services can reach remote or underserved regions and support aviation and maritime operations, among others.

Challenges include the cost and complexity of launches, space debris and end-of-life disposal, spectrum regulation by ITU, licensing, and environmental impacts. Security concerns involve jamming and spoofing, while weather and atmospheric conditions can affect signal quality, especially in certain bands.