# How Satellites Use Lasers and Colors to Send Data Fast > This patent describes a satellite communication system that uses two low-orbit satellites linked by a high-speed laser beam, which splits light into different colors to send massive amounts of data quickly between ground stations or aircraft. - **Patent:** US 8693947 - **Original title:** Extensible high bandwidth global space communication network - **Owner:** Raytheon - **Granted:** 2014 - **Status:** Active - **Times cited:** 2 - **Field:** telecommunications, aerospace, software, consumer_electronics ## What it does The patent describes a communication system using two satellites in low or medium Earth orbit (LEO/MEO) to relay data. A first satellite talks to a ground station or an aircraft (a "first transceiver" per claim 1 and 2) using a radio or laser link (claim 14). This first satellite then sends data to a second satellite using a special "laser communication crosslink" (claim 1). This laser link is very fast because it uses "wavelength division multiplexing" (WDM), meaning it sends data on multiple different colors of light at the same time (claim 1). The second satellite then sends the data down to another ground station (a "second transceiver" per claim 1 and 5). For example, an unmanned aerial vehicle (UAV) could send surveillance data to a first satellite, which beams it via laser to a second satellite, which then sends it to a ground control station in near real-time (claims 4, 8, 9). ## What it does NOT cover - Communication systems where satellites are only linked by radio frequency (RF) signals, as it specifically requires a "laser communication crosslink" (claim 1). - Laser communication crosslinks that do not use "wavelength division multiplexing" (WDM) to increase data rate (claim 1). - Satellite systems where both satellites are in geostationary orbit, as it specifies LEO or MEO below 36,000 km (abstract). - Systems where the satellites cannot autonomously compute a data route, as claim 16 describes this as an optional feature. - Systems that do not achieve low latency (less than 100 ms) or high data rates (greater than 1 gigabit per second) as specified in claims 9, 10, and 11. ## The clever bit The novelty lies in combining low-Earth orbit satellites with high-bandwidth laser communication crosslinks that specifically use wavelength division multiplexing. This allows for extremely fast, secure data transfer between satellites, overcoming the limitations of traditional radio links and enabling rapid relay from mobile platforms to ground stations. ## Real-world examples 1. Starlink's inter-satellite laser links 2. Project Kuiper's planned inter-satellite laser links 3. Military secure data relay networks 4. High-bandwidth communication for unmanned aerial vehicles (UAVs) ## Why it matters This patent from Raytheon focuses on creating a robust, high-speed communication network for applications requiring fast data transfer, particularly for military or intelligence operations involving airborne assets like UAVs. The use of laser crosslinks and WDM allows for much higher bandwidth and lower latency than traditional radio frequency satellite links. This technology is foundational for secure, real-time data relay in challenging environments, supporting critical missions. ## Frequently asked questions ### What does How Satellites Use Lasers and Colors to Send Data Fast cover? This patent describes a satellite communication system that uses two low-orbit satellites linked by a high-speed laser beam, which splits light into different colors to send massive amounts of data quickly between ground stations or aircraft. ### Who owns patent US 8693947? Raytheon owns this patent, granted in 2014. ### When does this patent expire? This patent is expected to expire on May 27, 2031, when the invention enters the public domain. ### What is patent US 8693947 cited by? This patent has been cited by 2 later patents that build on its ideas. ### What problem does this patent solve? This patent from Raytheon focuses on creating a robust, high-speed communication network for applications requiring fast data transfer, particularly for military or intelligence operations involving airborne assets like UAVs. The use of laser crosslinks and WDM allows for much higher bandwidth and lower latency than traditional radio frequency satellite links. This technology is foundational for secure, real-time data relay in challenging environments, supporting critical missions. ### What does this patent NOT cover? Communication systems where satellites are only linked by radio frequency (RF) signals, as it specifically requires a "laser communication crosslink" (claim 1). **Full plain-English explainer:** https://patentbrief.org/patent/us/8693947/extensible-high-bandwidth-global-space-communication-network **Original patent:** https://patents.google.com/patent/US8693947 --- _Source: PatentBrief — https://patentbrief.org. Patent facts are from public records; the plain-English explanation is PatentBrief's._ ## Related patents Semantically similar inventions in the PatentBrief corpus: - [How Satellites Handle Super Fast User Data Using Shared Antennas](https://patentbrief.org/patent/us/8135338/satellite-system-with-enhanced-payload-capacity) — This patent describes a satellite system boosting data capacity by having satellites receive high-speed user data, relay it via crosslinks to other satellites, and then send it to ground stations, often using a single antenna for both user and ground connections. - [High-Flying Aircraft Relays Satellite Internet to Ground Users](https://patentbrief.org/patent/us/10707961/adaptive-communication-system) — This patent describes a communication system that uses satellites, high-altitude aircraft, and ground stations to send data, specifically using lasers for space links and cloud-penetrating radio waves for ground links. - [How High-Altitude Satellites Relay Data for Fast-Moving Low-Orbit Satellites](https://patentbrief.org/patent/us/10998965/high-throughput-satellites-and-methods-of-operating-high-throughput-satellites-f) — 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. - [How LEO Satellites Switch Beams for Speed and Avoid Interference](https://patentbrief.org/patent/us/11902010/dual-leo-satellite-system-and-method-for-global-coverage) — This patent describes a Low Earth Orbit (LEO) satellite system that provides global internet by switching users to faster, focused beams when needed, while also preventing interference with older, higher-orbit satellites. - [How Satellites Send Internet Signals Using Light Beams](https://patentbrief.org/patent/us/10075242/high-throughput-satellite-system-with-optical-feeder-uplink-beams-and-rf-service) — This patent describes a ground system that sends many internet data streams to a satellite using a single optical light beam, allowing the satellite to broadcast radio signals without needing to change their frequency.