Monday, August 31, 2015

Canadian NewSpace Start-Up to Offer Commercial Satellite Repeaters

          By Chuck Black

The recent announcement that Canada will install twenty-four custom search-and-rescue signal repeaters on-board US Air Force next generation global positioning satellites, as part of the quarter billion dollar Canadian Medium Earth Orbit Search and Rescue (MEOSAR) satellite project, highlights the growing need for satellites to maintain full time contact with ground stations where the data can be collected and acted upon.

Retrieving data from a satellite requires a line-of-sight between the ground station and satellites, and for non-geosynchronous satellites this means being able to relay data to any specific ground station for a short period during each orbit. This makes it difficult for satellite operators to manage tasks requiring real-time communications, such as live aircraft tracking, disaster management, or spacecraft command and control. The typical solution to the problem is to build multiple ground stations which can be used during different points in the orbit. But satellite constellations, such as the 24 satellites being used for the US Air Force next generation global positioning satellites, can also be built with "repeaters," which amplify and re-transmit signals to other satellites within the constellation and then to line-of-sight ground stations. Not only can repeaters cost less than additional ground stations, but geopolitical constraints often limit where they can be placed. Graphic c/o Terracom/ Planet Labs.

Kepler Communications, a small Toronto, ON based start-up sees the potential for commoditizing inter-satellite communications, and is building commercial “off the shelf” re-transmitters (or "repeaters") able to work on a wide variety of satellites. As outlined by Kepler co-founder Jeffrey Osborne, "a fundamental transformation is happening today in the space industry" and his company aims to take advantage of it.

According to Osborne, an industry once dominated by custom spacecraft built only by national civilian and military agencies is rapidly being superseded by smaller, lower-cost platforms built by private companies utilizing a standardized micro-satellite or satellite bus.

If history is any guide, these standardized satellites will eventually also standardize their other components, including their communications capabilities.

Osborne thinks that the best way to capitalize on this trend is to design and build a standardized repeater which can be installed and used by any satellite, in much the same way that people making phone calls use the same terrestrial network in order to complete their calls. To this end, Kepler is developing inter-satellite networking options including an S band repeater for low data-rate local area networks, and electrically steerable X band antennas for higher data-rate and long-distance inter-satellite communications, with particular focus on usage within the emerging small satellite market.

Specs for what Kepler calls the "companion ad-hoc" network, a standardized satellite modem which will create an S band network allowing satellites to communicate with each other. According to Osborne, Kepler’s initial funding was provided by the University of Toronto Institute of Aerospace Studies (UTIAS) Start Entrepreneurship Program. The program is sponsored by Francis Shen, the founder of Aastra Technologies. Graphic c/o Kepler Communications.

Through their S band repeater, Kepler is investigating building an ad hoc network by coordinating with upcoming missions to host their payload. However, this comes with substantial challenges, as Osborne describes, such as “ensuring data ownership at every step in the link, regulatory hurdles not only in terms of spectrum allocations but also in terms of the type of data that can be sent through an inter-satellite link, as well as the actual technical aspect of routing data through a constantly changing network topology.”

The real benefit of inter-satellite communications comes when it is possible to send large quantities of data over very large distances, and to this end he company is also developing a "highly directional electrically steerable antenna," in addition to the base repeater. The unit would increase data transfer speeds by up to 35% without the need for mechanical actuation or spacecraft slew operations required by other directional antennas, and would allow high-speed inter-satellite links in a small satellite package. The component will add less than 150 grams to the total weight of the repeater.

The company has also developed plans for a constellation of 50 dedicated satellites located in five separate polar orbits, in order to provide a ready built satellite network of data relays which will support the communications network.

As outlined in the Kepler literature, the company founders and supporters include a range of well known space and IT focused entrepreneurs and academics. Graphic c/o Kepler Communications.

Of course, an expensive 50-satellite constellation is still a thing for the future. For now, the focus of the Kepler offering will be technologies and services for inter-satellite communications.

Chuck Black
As long as Osborne and his colleagues are able to provide a lower cost than the Canadian government was able to provide for the MEOSAR search-and-rescue signal repeaters, then Kepler's future might end up looking very bright indeed.

Chuck Black is the editor of the Commercial Space blog.

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