From Telesat press release : 9 February 2021

Telesat has entered into an agreement with Thales Alenia Space to be the prime manufacturer of Telesat’s global LEO constellation called Lightspeed.

The initial constellation will comprised of a fleet of 298 satellites

Operating at 1,000 km height will provide minimal latency compared with geostationary and medium Earth orbits.

Lightspeed satellites will incorporate sophisticated phased array antennas on each satellite that are combined with advanced beam hopping technology to create approximately 135,000 beams that can dynamically focus multiple Gbps of capacity.

The capacity is claimed to be an order of magnitude higher than any other system into hot spots like remote communities, large airports or major sea ports.

Nearly 1,200 high capacity optical inter-satellite links, four on each satellite will allow fewer gateway earth stations and provide a highly resilient, flexible and secure space-based IP network.

Data processing will occur in space, with digital modulation and  demodulation on the satellite, coupled with a revolutionary end-to-end network operating system, that improves link performance and gives customers unprecedented flexibility for routing traffic across the globe, eliminating gateway hops for the fastest, most secure, end-to-end delivery of data.

The proposed constellation architecture is patent-pending and features satellites operating in both polar and inclined orbital planes. This results in full pole-to-pole global coverage, concentrating capacity in areas where it is most needed to maximize network efficiency and achieve superior unit cost economics.

Read more at the Telesat web site. Press release about Lightspeed agreement between Telesat and Thales