Tuesday, September 04, 2018

Might CubeSats provide broadband Internet connectivity one day?

It's hard to believe that the capability of the satellites companies like OneWeb and SpaceX are contemplating might one day fit in a CubeSat, but think about the phone in your pocket.

In November, 2016, SpaceX filed a request for approval to launch 4,425 Internet-service satellites using the Ku and Ka frequency bands. The satellites were expected to measure 4 x 1.8 x 1.2 meters. In February, 2018 SpaceX launched two Internet-service test satellites -- TinTin A and B -- that measured only 1.1 x .7 x .7 meters.

Why the size difference?

Maybe some functions were omitted from the test satellites -- for example, they may not have included inter-satellite laser communication capability -- but technical progress also steadily reduces the size of electronic devices.

Might the capability TinTin A or B one day be packaged in a CubeSat?

A CubeSat is a small satellite composed of one or more 10 x 10 x 10-centimeter cubes (units) that weigh under 1.33 kg each. For example, the 3-unit (3U) CubeSat shown below would be 10 x 10 x 30 centimeters (plus a little more for the frame holding the cubes) and weigh under 3.99 kg.

Assembling a 3U CubeSat

CubeSats were initially developed to support low-cost access to space for university research, but today they are being used in both commercial and research projects and many companies are manufacturing CubeSats and components.

Several startup companies are working on narrowband communication applications. Let's look at two examples.

SAS equatorial orbits (source)
Skyandspace (SAS) is off to an early start. They have three 3U CubeSats in an equatorial orbit and they have demonstrated instant messageing, voice calls, financial transactions and integration with public switched telephone network.

They plan to begin launching a 200-satellite constellation next year and to be fully operational in 2020. When complete, the constellation will serve the +/- 15-degree latitude region and provide personal voice calls and messages and connectivity for machine-machine communication and "Internet of things" applications.

SAS CEO Meir Moalem estimates that the "full constellation of the 200 nanosatellites will cost somewhere between $120 and $160 million,” which, he said includes "the production, launch, and operation of the constellation." They expect that that relatively low cost will enable them to replace 25% of the constellation each year, enabling them to constantly upgrade their technology. (APP Company Research used a figure of $150 million in an independent forecast).

SAS hopes to eventually provide global narrowband coverage with 1,000 satellites, but they are not talking about broadband service. On the other hand, "Internet in space" is the long-term goal of Kepler Communications.

Kepler KIPP (source)
Just over two years after the company was founded and a year after being funded, Kepler had KIPP, their first operational satellite, in orbit -- a testimony to CubeSat cost and development time.

KIPP, a KU-band, 3U CubeSat, is in polar orbit and providing high-speed, global store-and-forward service through their gateways in Inuvik and Svalbard. They are serving customers with latency-tolerant applications like bulk transfer of scientific and video data. (This is reminiscent of the first satellite Internet project I know of -- VitaSat -- which provided email and other asynchronous services in developing nations in the mid-1990s).

The next launches will be CASE, a slightly upgraded version of KIPP, which will add to their store-and-forward capacity and TARS, a redesigned 6U CubeSat that will be used for both store-and-forward and Internet of things applications. TARS will be the final service-demonstration satellite prior the early 2020 launch of the first 10 satellites of their 140 satellite constellation.

Both SAS and Kepler are small startups. SAS has issued stock and Kepler is venture funded. Kepler has also received In-Orbit Demonstration Mission funds from Satellite Applications Catapult, a non-profit company funded by Innovate UK which in turn is funded by UK Research and Innovation. (This sounds like an interesting public-private funding chain).

Like OneWeb (and unlike SpaceX), both work with partners in design and production of satellites, antennas, radios, etc. and both sound like fast-moving, innovative companies with a sense of purpose -- reminiscent of the early days of both personal computing and the Internet. The "careers" page of the Kepler Web site captures this feeling well. It offers the opportunity to "join the team that's building the Internet in space," recognizes that "a good cultural fit can oftentimes be more important than technical competency when building a company" and lists "indoor bike storage" as one of the perks of employment. I'm ready to sign up!

It's hard to believe that the capability of the satellites companies like OneWeb and SpaceX are contemplating might one day fit in a CubeSat, but think about the phone in your pocket. Also, as the following time-lapse video (1:54) shows, today's CubeSats are hand built -- what would mass-produced CubeSats cost and how many could a BFR launch at once?