WASHINGTON — As it explores changes to its constellation orbit and spacecraft design, Kepler Communications on Oct. 7 said it nonetheless secured launch slots for its first two fully commercial satellites.
Kepler will launch the two six-unit cubesats on a Russian Soyuz rocket operated by GK Launch Services in mid-2020. Kepler arranged the launch through Innovative Space Logistics, the Dutch launch broker that arranged for Keplers first two prototypes to launch in 2018 on a Chinese Long March 11 and Indian PSLV.
Jared Bottoms, Kepler’s head of launch and satellite programs, said the Toronto startup still plans to deploy a 140-satellite constellation starting with at least 15 commercial spacecraft by the end of 2020, but is mulling changes after SpaceX started launching its first satellites toward a 550-kilometer orbit this May.
Kepler’s prototype satellites operate in low Earth orbits between 500 and 600 kilometers. The overlap in with SpaceX’s Starlink broadband constellation has Kepler concerned about a spike in conjunction alerts as satellites fly past each other, as well as a risk of increased signal interference.
In an interview, Bottoms said Kepler has resolved to place future satellites at 575 kilometers so that they stay above the 1,584 Starlink satellites SpaceX plans to operate at 550 kilometers.
“From an architectural standpoint, we are really looking at how can we adapt to prevent the dramatic increase of possible conjunctions that we might see,” he said. “That’s been our number one focus.”
Kepler has two more launches next year planned in addition to the GK Launch Services Soyuz mission, he said. The company aims to have all 140 satellites in orbit in 2023, according to a news release.
Bottoms said Kepler has procured spacecraft platforms for the two satellites it will launch with GK Launch Services, but declined to name a provider or providers. The satellites have a “matured” design, he said, with upgraded components including a more powerful software-defined radio.
Kepler has other upgrades planned as it builds out its Internet-of-Things connectivity constellation. Bottoms said the company hopes to incorporate propulsion next year, and is weighing electronically steered antennas for narrowband services.
Kepler has been using attitude control systems like brake pads when faced with conjunction alerts, as well as to reorient its satellites to direct beams at customers, Bottoms said. With an electronically steered antenna onboard, Kepler can guide beams electronically instead of reorienting spacecraft, he said.
Bottoms said Kepler’s early launch plans rely heavily on rideshare opportunities. As Kepler builds towards 140 satellites, it will consider dedicated smallsat launchers to fill out orbital planes, he said. Replacing individual spacecraft is something Kepler will likely do with more rideshares, he added.
Bottoms said Kepler has a third and final prototype scheduled for a Soyuz launch in February. Kepler spokesperson Victoria Alberto said the launch for the prototype, called TARS, was not arranged with GK Launch Services and Innovative Space Logistics. She declined to provide additional details about the satellite’s launch.
Kepler’s satellites, starting with TARS, will feature narrowband payloads for low-data-rate connectivity in addition to Ku-band. Kepler is using Ku-band for high-data-rate services like transferring video files from offshore oil rigs back to land.