Space News by Caleb Henry — July 26, 2017
Satellite fleet operator Telesat, whose first two low-Earth orbit satellites launch later this year, says latency was the critical factor in deciding to invest in a high-throughput, non-geosynchronous constellation.
Dan Goldberg, president and CEO of Telesat, said during a July 26 conference call with investors that while the Ottawa, Canada-based company is still spending on geostationary high throughput satellites (HTS), including two slated to launch next year, it was the need for faster broadband services in the future that drove the decision to favor a closer orbit.
“You can launch very large, high throughput satellites in GEO, kind of terabit-plus type satellites to try to answer those requirements,” Goldberg said, describing said requirements as unsurprisingly more bandwidth at a lower cost. “Those satellites serve a lot of applications, and they serve a lot of applications very well … but what they don’t answer is the latency issue, which we think is an important issue today but we think even more so it’s going to become an increasingly important consideration in the future.”
Latency in satellite networks is largely driven by orbit, and medium Earth orbit operator O3b Networks, now a part of SES, frequently championed the reduced latency advantage of having satellites in orbit 8,000 kilometers up compared to 36,000 kilometers where geostationary satellites reside. Industry has and still does debate the significance of latency, depending on the applications served, but the growing number of LEO systems suggests a changing tide in that discussion. Low latency is a core tenant of OneWeb’s LEO-HTS constellation, which counts Intelsat among its investors. Similarly LeoSat argues that latency will be a discriminating factor for its constellation, as has corporate backer Sky Perfect JSAT of Japan.
More:
http://spacenews.com/telesat-says-low-latency-led-to-leo-constellation/
