SpaceX receives authorisation to operate satellite in e-band

SpaceX has received partial authorisation from the Federal Communications Commission (FCC), the US agency that regulates radio, television, wire, satellite and cable communications, to build, deploy and operate a constellation of non-geostationary orbit (NGSO) satellites, known as the “second generation” of the Starlink constellation.

The concession limits future communication to the 71.0-76.0 GHz (Earth-space) and 81.0-86.0 GHz (Earth-space) frequency bands, collectively called the e-band, using 7,500 Starlink Gen2 satellites.

This authorisation will allow SpaceX to use the full capacity of the Starlink Gen2 satellites, improving the broadband service offered in the United States, including those in unserved and underserved areas of the country. The use of the E-band will be for communication between satellites and ground stations, and not with user terminals.

However, the FCC has made the grant conditional on SpaceX coordinating its use of the band with any other operator that may also be authorised to operate in the E-band. In addition, SpaceX may also have to modify its operations to guarantee the protection of adjacent frequency services in the event that other operators start operating in the same bands. In short, this authorisation does not guarantee that SpaceX will always be allowed to operate as proposed in the document.

So far, the bands used by SpaceX satellites to provide broadband Internet services are Ka (frequencies from 27 GHz to 40 GHz, the main one for communication with satellites) and Ku (12 GHz to 18 GHz). SpaceX has also been authorised to use the V-band using up to 7,500 Starlink Gen2 satellites, instead of deploying a separate V-band system. SpaceX is authorised to operate in the V-band with Gen2 satellites (37.5-40.0 GHz and 40.0-42.0 GHz bands for space-Earth and 47.2-50.2 GHz and 50.4-51.4 GHz for Earth-space).

Last October, SpaceX submitted an application to the International Telecommunications Union (ITU) to operate a constellation of around 30,000 satellites in 288 orbital planes and at altitudes between 350 km and 614 km. The network, called ESIAFI II, plans to use W-band frequencies for fixed and mobile satellite services. The application was made through the island of Tonga, in the Pacific region, as a regulatory base. The information is from the Space Intel Report website.

Looking for more speed

As of mid-March 2024, there were 5,591 Starlink satellites in orbit (3647 first generation and 1944 second generation); of this total, 5,529 were operational orbiting around 550 kilometres from the Earth’s surface, according to the website of astronomer Jonathan McDowell, who tracks constellations. Starlink has an interactive map detailing the locations where the satellites are available and which areas are on a waiting list and which should be covered soon.

Serving more than 2.5 million customers worldwide, the service offered by Starlink is currently slower than most terrestrial fibre networks usually offer, with average latency of more than 30 milliseconds at best, and double that at peak times. Elon Musk said that Starlink’s main objective technically speaking is to deliver average latency of less than 20 milliseconds.

To achieve this goal, Starlink submitted a letter to the FCC requesting permission to operate a VLEO (Very Low Earth Orbit) constellation at lower altitudes, in the 340 km to 360 km range, and thus shorten the distance for data transfer and consequently reduce latency.

Stated in the document, Starlink argued that operating at lower altitudes will allow it to provide better quality satellite services and lower latency, keeping up with the growing demand for this type of real-time connectivity for applications such as remote working, distance education, telehealth and emergency response. In addition, lower latency is particularly important for rural and remote areas that don’t have terrestrial broadband and for terrestrial broadband networks that rely on satellite backhaul.

Starlink also cited that the probability of collision of second-generation satellites in lower layers is much lower than that of its satellites operating in higher orbits. In addition, de-orbiting satellites would take a matter of weeks, not only in the post-deployment period, but also throughout the satellites’ lifetime.

The FCC repeated a negative response already given to another Starlink request in December 2022. On that occasion it imposed limitations to protect other satellite and terrestrial operators from interference and to maintain a safe space environment by promoting competition and protecting spectrum and orbital resources for future use.

In its response of 8 March, the FCC reiterated that Starlink would not be authorised to deploy satellites in very low orbits, specifically below the operational altitudes of the International Space Station, which can reach up to 370 km.

In an interview with the  IEEE Spectrum website, John Crassidis, professor of mechanical and aerospace engineering at the University of Buffalo, says he is not convinced that VLEO satellites would be so harmful. “I think the FCC may be overreacting. We’ll know where all the satellites are, we’ll be able to observe them and avoid them,” he explains.

Those who disagree with this idea say that the lower orbits are almost empty compared to the higher ones, but there are risks of collisions with satellites in transit to their operational altitudes and even uncontrolled falling objects. This is the case for Hugh Lewis, professor of astronautics at the University of Southampton in the UK. “We don’t sufficiently understand the risks, especially as the number of satellites that SpaceX is proposing is greater than those that have already been launched,” he says.