Telesat, a global leader in satellite communications, is set to redefine the future of broadband connectivity with its latest innovation, Telesat Lightspeed. This cutting-edge low Earth orbit (LEO) satellite network is designed to deliver high-quality, low-latency broadband to users worldwide, marking a significant leap forward in satellite communication technology.

With over 50 years of experience in geostationary (GEO) satellite operations, Telesat is now shifting its focus to a next-generation satellite network. Telesat Lightspeed is a state-of-the-art constellation of 198 LEO satellites positioned approximately 1,300 km above Earth. This network leverages the Ka-band spectrum, the industry standard for high-capacity satellite communication, to provide users with seamless and resilient broadband connectivity.

Advanced Technologies for Seamless Connectivity

The Telesat Lightspeed architecture offers redundancy at multiple levels to ensure highly resilient service to a user terminal.

• Multiple LEO Satellites for Higher Space Resiliency: The Telesat Lightspeed constellation will have satellites that are interconnected in a mesh via optical links. Furthermore, multiple satellites are in the view of a user terminal, unlike GEO systems where there is only one visible satellite.  Multiple satellites translate to multiple transport route options to connect a user terminal. The network will decide the optimal satellite assignment and traffic routing to favor long-term availability (e.g., paths avoiding rain cells) to ensure that users get their provisioned data rates and performance. 
• Ground Resiliency: Each satellite has four feeder link antennas. Multiple feeder link antennas per satellite enable simultaneous connections to multiple Landing Stations for seamless handovers. Each Landing Station consists of multiple tracking antennas that communicate with the satellites. Multiple Landing Stations connecting to a Point of Presence (PoP) with seamless switchover capability provide redundant paths in the case of weather impairment at one of the Landing Stations. All of the ground facilities will be orchestrated by Telesat’s network management system so the network can dynamically adapt to network and weather events.
• Dynamic User Links Adapt to Local Environment: LEO satellites are about 35x closer to Earth than GEO (1,000km vs 35,000km), bringing a significant advantage in terms of user link performance. All else being equal, LEO RF user links are about 25 dB stronger than GEO RF user links. Telesat Lightspeed satellites are designed using state-of-the-art technologies, with the ability to optimize resources for degraded local environment conditions such as rain fade. The Telesat Lightspeed system will employ advanced mechanisms to ensure resource allocation to users can adapt to the local user environment. For example, dynamic monitoring of transmissions to detect when rain fades is interfering with signal strength and adjust power levels automatically to compensate. Automated software tools will be used to ensure optimal use of resources while being more resilient to rain Additionally, near real-time adjustments to the terminal's burst time plan and beam hop plan (FBHP) will be used to allocate more slots to lower-performing channels, alleviating the negative effects of rain fade.
• 24/7 Monitoring and Support: Telesat is one of the most innovative global satellite operators and currently owns and manages a fleet of geostationary (GEO) satellites. The global GEO satellite fleet provides coverage and connectivity solutions in the C, Ku, and Ka bands. Telesat has more than five decades of experience in ensuring that communication services provided to its customers remain connected through all adverse conditions that impact the network. All routine operations within Telesat’s Satellite Control Center are conducted using automated procedures run by master schedulers residing on the fleet control systems. Operations are monitored around the clock at Telesat’s Satellite Control Centre and a team of experienced senior engineers are always on hand to troubleshoot any critical anomalies. This legacy of engineering excellence, reliability, and industry-leading customer service will continue into the new Telesat Lightspeed era.

Telesat has been at the forefront of innovation in satellite technology for more than half a century. With Telesat Lightspeed, the company is setting new benchmarks in connectivity, offering a highly resilient and dynamic LEO satellite system tailored for enterprise, maritime, aviation, and remote operations.

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