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Strengthening IoT through Space Based Communication

The 50th anniversary of the first human moon landing is upon us. As the Apollo 11 retrospective swirls around us, we’ve decided to take a look at today’s efforts to return to the moon and this time, to build habitable lunar bases.

What will it take? Which rockets and landers will get us there?

We can know that by understanding IOT through space based communication.

SPACE may not be the final frontier for the Internet of Things, but evidence is mounting that it could be the technology’s next golden opportunity. While we’re still a way away from the IoT in space becoming a commercially viable mainstream technology, a variety of companies are pushing the envelope in two significant ways.

First, companies are working to realize the promise of satellite-powered networks that would bring the Internet of Things everywhere on earth. Second, vendors — and NASA — are exploring actual IoT applications and use cases beyond Earth’s atmosphere, in satellites and rockets.

It’s long been a goal to use satellites to provide simple, low-power, low-cost, IoT-friendly networks for remote users outside of the coverage areas of standard terrestrial networks. But due to the distances involved and other factors, traditional approaches to space-based IoT networks have tended to be expensive, power-hungry, and complex, limiting the economic benefit of the technology. That hasn’t stopped companies from trying, though. Last month, cloud leader Amazon Web Services (AWS) struck a deal with satellite provider Iridium to “bring internet connectivity to the whole planet.” The deal calls for them to develop a satellite-based network called Cloud Connect, designed specifically for IoT applications.

Similarly, earlier this month, U.S.-based Orbcomm, which provides satellite IoT and machine-tomachine communications services, announced it will work with Asia Pacific Navigation Telecommunications Satellite (APNTS) to provide its services in China.

Even if satellite IoT may not be ready for prime time, IoT actually in space is probably a bigger market opportunity than actually using the IoT in space. Still, IoT technology is potentially a good match for many extra-terrestrial applications. In fact, NASA tested a couple of initial use cases in early 2017. One test involved using wireless communications to transmit important orbital data within a Technical and Educational Satellite 5 (TechEd Sat 5) released from the International Space Station. The goal is to use wireless networking to reduce weight to allow increased payload, an approach that could eventually become the standard in satellite design.

Today, space agencies prefer to use radios in the S band (2 to 4 gigahertz) and Ka band (26.5 to 40 GHz) for communications between spacecraft and mission control, with onboard radios transmitting course information, environmental conditions, and data from dozens of spaceflight systems back to mission control. The Ka band is particularly prized—Don Cornwell, who oversees radio and optical technology development at NASA, calls it “the Cadillac of radio frequencies”— because it can transmit up to gigabits per second and propagates well in space.

Any spacecraft’s ability to transmit data is constrained by some unavoidable physical truths of the electromagnetic spectrum. For one, radio spectrum is finite, and the prized bands for space communications are equally prized by commercial applications. Bluetooth and Wi-Fi use the S band, and 5G cellular networks use the Ka band.

THE GATEWAY, scheduled to be built in the 2020s, will present a far bigger opportunity for high-speed laser communications in space. NASA, with help from its Canadian, European, Japanese, and Russian counterparts, will place this space station in orbit around the moon; the station will serve as a staging area and communications relay for lunar research.

The Gateway offers an opportunity to build a permanent optical trunk line between Earth and the moon. One thing NASA would like to use the Gateway for is transmitting positioning, navigation, and timing information to vehicles on the lunar surface. “A cellphone in your pocket needs to see four GPS satellites,” says Schier. “We’re not going to have that around the moon.” Instead, a single beam from the Gateway could provide a lunar rover with accurate distance, azimuth, and timing to find its exact position on the surface.

After eight years of development, the BE-4 represents the cutting edge of rocket science. It promises to be simpler, safer, cheaper, and far more reusable than the engines of previous years. Blue Origin is also working on two other engines, including one (the BE-7) destined for the company’s Blue Moon lunar lander. But the BE-4 is the largest of the three, designed to generate as much as 2,400 kilonewtons of thrust at sea level.

 

Though there have been advancements in satellite building and launching technologies, access to space has been expensive and many scientific challenges still exist. An important question is how these existing sensors and actuator systems in satellites should be adapted to form SWANS so that the solution is inexpensive, reliable and efficient. Since the beginning of the satellite era, there always has been demand for mass production, miniaturization, low-cost solutions, innovative system designs, reliable inter-networking of satellites, etc., for space applications but much exploration is yet to be done to meet these requirements. Compared to the terrestrial applications, the implementation of SWANS in the form of wireless networked satellite systems, constellations of (tiny) satellites in space or inter-satellite communication and computing requires innovation, optimization of space and weight, and higher levels of reliability. They should withstand the harsh space environments such as extreme temperatures, high mobility, power constraints, and undesirable perturbations which influence their operation significantly. The wireless communication between two modules in the network will rely on the inter-satellite link or intrasatellite link, whose establishment and stability are impacted by the satellite orbit and attitude, antenna configuration, mobility or the layout of spacecraft. If the communication range of each node is limited, the nodes may use multi-hop communication to send their data to the destination. This requires a complex control, and should adopt an auto configuration and routing strategy to ensure time and energy optimization as they are resource constrained.

 

 

 

Report by
Shahin Akter;
Department of Electrical and Electronic Engineering (EEE);
Chittagong University of Engineering and Technology (CUET);
Year: 3rd