How High-Altitude Satellites Relay Data for Fast-Moving Low-Orbit Satellites

This patent describes how a high-throughput satellite (HTS) in a fixed orbit can dynamically track and relay data from fast-moving low-earth orbit (LEO) satellites to ground stations by precisely switching its focused radio beams.

What it covers

This patent details a method for a high-throughput satellite (HTS) to act as a data relay for low-earth orbit (LEO) satellites. The system first predicts the path of an orbiting LEO satellite (Claim 1). Based on this predicted path, it identifies a sequence of specific radio beams, called spot beams, on the HTS that have compatible radio properties, known as 'matching color re-use polarization' (Claim 1). This information is then sent to the HTS, instructing it to seamlessly hand off the communication link from one spot beam to the next as the LEO satellite moves, ensuring a continuous connection (Claim 1). For example, if a LEO satellite is transmitting weather data, the HTS would anticipate its movement across its coverage area and automatically switch the focused radio beam to maintain a strong inter-satellite link, even adjusting data transmission settings (MODCOD) if ground station weather degrades the signal (Claim 2, 4).

What it doesn't cover

• —Does not cover relaying data between satellites without using a High Throughput Satellite (HTS).
• —Does not cover inter-satellite links that do not involve dynamically assigning spot beams based on a LEO satellite's trajectory.
• —Does not cover maintaining an inter-satellite link without considering 'matching color re-use polarization' for the spot beams.
• —Does not cover direct communication from a LEO satellite to a ground station without an HTS acting as a relay.
• —Does not cover systems where the HTS spot beams are static and do not adapt to the LEO satellite's movement.

The clever bit

The innovation lies in dynamically predicting a fast-moving LEO satellite's path and then precisely instructing a geostationary HTS to switch its highly focused spot beams, ensuring a continuous, high-quality inter-satellite link by selecting beams with compatible radio properties.

Why it matters

LEO satellites, like those used for global internet or Earth observation, move very quickly and are only visible to a ground station for short periods. This patent provides a way for a geostationary HTS to extend the communication window for LEO satellites, making data transfer more efficient and reliable. By using an HTS as a relay, LEO operators can reduce the number of expensive ground stations needed worldwide.

Real-world examples

• 1.LEO satellite internet constellations (e.g., Starlink, OneWeb)
• 2.Earth observation satellite data relay
• 3.Global maritime and aviation communication networks
• 4.Military satellite communication systems